MORGAN STANLEY DEAN WITTER US GOVERNMENT MONEY MARKET TRUST
485BPOS, 1999-03-29
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<PAGE>
     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MARCH 29, 1999
 
                                                     REGISTRATION NOS.:  2-74980
                                                                        811-3326
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                              --------------------
 
                                   FORM N-1A
                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933                     /X/
                          PRE-EFFECTIVE AMENDMENT NO.                        / /
                       POST-EFFECTIVE AMENDMENT NO. 20                       /X/
                                     AND/OR
              REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY
                                  ACT OF 1940                                /X/
                               AMENDMENT NO. 21                              /X/
 
                            ------------------------
 
         MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
           (FORMERLY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST)
                        (A MASSACHUSETTS BUSINESS TRUST)
               (EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)
 
                             TWO WORLD TRADE CENTER
                            NEW YORK, NEW YORK 10048
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICE)
 
       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (212) 392-1600
 
                                BARRY FINK, ESQ.
                             TWO WORLD TRADE CENTER
                            NEW YORK, NEW YORK 10048
                    (NAME AND ADDRESS OF AGENT FOR SERVICE)
                         ------------------------------
 
                                    COPY TO:
                            DAVID M. BUTOWSKY, ESQ.
                             GORDON ALTMAN BUTOWSKY
                             WEITZEN SHALOV & WEIN
                              114 WEST 47TH STREET
                            NEW YORK, NEW YORK 10036
                              --------------------
 
                 APPROXIMATE DATE OF PROPOSED PUBLIC OFFERING:
 
 As soon as practicable after this Post-Effective Amendment becomes effective.
 
 IT IS PROPOSED THAT THIS FILING WILL BECOME EFFECTIVE (CHECK APPROPRIATE BOX)
 
        ___ immediately upon filing pursuant to paragraph (b)
 
        _X_ on March 29, 1999 pursuant to paragraph (b)
 
        ___ 60 days after filing pursuant to paragraph (a)
 
        ___ on (date) pursuant to paragraph (a) of rule 485.
 
           AMENDING THE PROSPECTUS AND UPDATING FINANCIAL STATEMENTS
 
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
<PAGE>
         MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
 
                             CROSS-REFERENCE SHEET
 
                                   FORM N-1A
 
<TABLE>
<CAPTION>
ITEM                                               CAPTION
- ------------------------------------------------------------------------------------------
<S>                 <C>
PART A                                            PROSPECTUS
 1.  ............... Cover Page; Back Cover
 
 2.  ............... Investment Objectives; Principal Investment Strategies; Principal
                     Risks
 
 3.  ............... Fees and Expenses
 
 4.  ............... Investment Objectives; Principal Investment Strategies; Principal
                     Risks
 
 5.  ............... Not Applicable
 
 6.  ............... Fund Management
 
 7.  ............... Pricing Fund Shares; How to Buy Shares; How to Exchange Shares; How to
                     Sell Shares; Distributions; Tax Consequences
 
 8.  ............... How to Buy Shares
 
 9.  ............... Financial Highlights
</TABLE>
 
PART B                   STATEMENT OF ADDITIONAL INFORMATION
 
    Information required to be included in Part B is set forth under the
appropriate caption in Part B of this Registration Statement.
 
PART C
 
    Information required to be included in Part C is set forth under the
appropriate item, so numbered, in Part C of this Registration Statement.
<PAGE>
                                                     PROSPECTUS - MARCH 29, 1999
 
Morgan Stanley Dean Witter
                                              U.S. GOVERNMENT MONEY MARKET TRUST
 
                                 [COVER PHOTO]
 
                                       A MONEY MARKET FUND THAT SEEKS TO PROVIDE
                                             SECURITY OF PRINCIPAL, HIGH CURRENT
                                                            INCOME AND LIQUIDITY
 
   
  The Securities and Exchange Commission has not approved or disapproved these
securities or passed upon the adequacy of this PROSPECTUS. Any representation to
                      the contrary is a criminal offense.
    
<PAGE>
CONTENTS
 
   
<TABLE>
<S>                       <C>                                                     <C>
The Fund                  Investment Objectives.................................                   1
                          Principal Investment Strategies.......................                   1
                          Principal Risks.......................................                   2
                          Past Performance......................................                   3
                          Fees and Expenses.....................................                   4
                          Fund Management.......................................                   5
 
Shareholder Information   Pricing Fund Shares...................................                   6
                          How to Buy Shares.....................................                   6
                          How to Exchange Shares................................                   8
                          How to Sell Shares....................................                  10
                          Distributions.........................................                  12
                          Tax Consequences......................................                  13
Financial Highlights      ......................................................                  14
 
Financial Statements --
January, 1999             ......................................................                  15
 
Our Family of Funds       ......................................................   Inside Back Cover
 
                          THIS PROSPECTUS CONTAINS IMPORTANT INFORMATION ABOUT THE FUND. PLEASE READ
                          IT CAREFULLY AND KEEP IT FOR FUTURE REFERENCE.
</TABLE>
    
 
           FUND CATEGORY
           ---------------------------
       / / Growth
 
       / / Growth and Income
 
       / / Income
 
       /X/ MONEY MARKET
<PAGE>
(SIDEBAR)
MONEY MARKET
A MUTUAL FUND HAVING THE GOAL TO SELECT SECURITIES TO PROVIDE CURRENT INCOME
WHILE SEEKING TO MAINTAIN A STABLE SHARE PRICE OF $1.00.
YIELD
THE FUND'S YIELD REFLECTS THE ACTUAL INCOME THE FUND PAYS TO YOU EXPRESSED AS A
PERCENTAGE OF THE FUND'S SHARE PRICE. BECAUSE THE FUND'S INCOME FROM ITS
PORTFOLIO SECURITIES WILL FLUCTUATE, THE INCOME IT IN TURN DISTRIBUTES TO YOU
AND THE FUND'S YIELD WILL VARY.
(END SIDEBAR)
 
THE FUND
 
ICON  INVESTMENT OBJECTIVES
- --------------------------------------------------------------------------------
           Morgan Stanley Dean Witter U.S. Government Money Market Trust (the
           "Fund") is a money market fund that seeks to provide security of
           principal, high current income and liquidity. There is no guarantee
           that the Fund will achieve these objectives.
 
ICON  PRINCIPAL INVESTMENT STRATEGIES
- --------------------------------------------------------------------------------
             The Fund will invest in high quality, short-term U.S. Government
             securities. The Fund's "Investment Manager," Morgan Stanley Dean
             Witter Advisors Inc., seeks to maintain the Fund's share price at
             $1.00. The share price remaining stable at $1.00 means that the
             Fund would preserve the principal value of your investment.
 
             The U.S. Government securities that the Fund may purchase include:
                            - U.S. Treasury bills, notes and bonds, all of which
                              are direct obligations of the U.S. Government.
                            - Securities issued by agencies and
                              instrumentalities of the U.S. Government which are
                              backed by the full faith and credit of the United
                              States. Among the agencies and instrumentalities
                              issuing these obligations are the Government
                              National Mortgage Association and the Federal
                              Housing Administration.
                            - Securities issued by agencies and
                              instrumentalities which are not backed by the full
                              faith and credit of the United States, but whose
                              issuing agency or instrumentality has the right to
                              borrow, to meet its obligations, from U.S.
                              Treasury. Among these agencies and
                              instrumentalities are the Federal National
                              Mortgage Association, the Federal Home Loan
                              Mortgage Corporation and the Federal Home Loan
                              Banks.
                            - Securities issued by agencies and
                              instrumentalities which are backed solely by the
                              credit of the issuing agency or instrumentality.
                              Among these agencies and instrumentalities is the
                              Federal Farm Credit System.
 
             The Fund also may invest up to 10% of its assets in FDIC insured
             certificates of deposit of banks and saving and loan institutions.
 
   
             The Fund's policies discussed above are fundamental. These policies
             may not be changed without shareholder approval. In addition to the
             fundamental investment policies, the Fund may invest in repurchase
             agreements. Repurchase agreements are contracts in which a
             financial institution sells a security and agrees to buy it back on
             a specific date (usually within 7 days) and at a higher price,
             which reflects an agreed-upon interest rate.
    
 
                                                                               1
<PAGE>
ICON  PRINCIPAL RISKS
- --------------------------------------------------------------------------------
 
            CREDIT AND INTEREST RATE RISKS. A principal risk of investing in the
             Fund is associated with its U.S. Government securities investments,
             which are subject to two types of risks: credit risk and interest
             rate risk. Credit risk refers to the possibility that the issuer of
             a security will be unable to make interest payments and repay the
             principal on its debt. Interest rate risk, another risk of debt
             securities, refers to fluctuations in the value of a fixed-income
             security resulting from changes in the general level of interest
             rates.
 
   
             Credit risk is minimal with respect to the Fund's U.S. Government
             securities investments. Repurchase agreements involve a greater
             degree of credit risk. The Investment Manager, however, actively
             manages the Fund's assets to reduce the risk of losing any
             principal investment as a result of credit or interest rate risks.
             In addition, federal regulations require money market funds, such
             as the Fund, to invest only in debt obligations of high quality and
             short maturities.
    
 
             An investment in the Fund is not a deposit of a bank and is not
             insured or guaranteed by the FDIC or any other government agency.
             Although the Fund seeks to preserve the value of your investment at
             $1.00 per share, if it is unable to do so, it is possible to lose
             money by investing in the Fund.
 
            YEAR 2000. The Fund could be adversely affected if the computer
             systems necessary for the efficient operation of the Investment
             Manager, the Fund's other service providers and the markets and
             individual and governmental issuers in which the Fund invests do
             not properly process and calculate date-related information from
             and after January 1, 2000. While year 2000-related computer
             problems could have a negative effect on the Fund, the Investment
             Manager and affiliates are working hard to avoid any problems and
             to obtain assurances from their service providers that they are
             taking similar steps.
 
2
<PAGE>
   
(SIDEBAR)
ANNUAL TOTAL RETURNS
THIS CHART SHOWS HOW THE PERFORMANCE OF THE FUND'S SHARES HAS VARIED FROM YEAR
TO YEAR OVER THE PAST 10 YEARS.
    
AVERAGE ANNUAL
TOTAL RETURNS
THIS TABLE COMPARES THE FUND'S AVERAGE ANNUAL RETURNS WITH THOSE OF A BROAD
MEASURE OF MARKET PERFORMANCE OVER TIME.
(END SIDEBAR)
 
ICON  PAST PERFORMANCE
- --------------------------------------------------------------------------------
   
           The bar chart and table below provide some indication of the risks of
           investing in the Fund. For the Fund's most recent 7-day annualized
           yield, you may call (800) 869-NEWS. The Fund's past performance does
           not indicate how the Fund will perform in the future.
    
 
ANNUAL TOTAL RETURNS - CALENDAR YEARS
 
EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC
 
<TABLE>
<S>        <C>
1989           8.59%
`90            7.35%
`91            5.37%
`92            3.03%
`93            2.29%
`94            3.22%
`95            5.02%
`96            4.47%
`97            4.63%
`98            4.71%
</TABLE>
 
During the periods shown in the bar chart, the highest return for a calendar
quarter was 2.22% (quarter ended June 30, 1989) and the lowest return for a
calendar quarter was 0.55% (quarter ended June 30, 1993).
 
   
<TABLE>
<CAPTION>
AVERAGE ANNUAL TOTAL RETURNS (FOR THE PERIODS ENDED THE 1998 CALENDAR YEAR)
- -------------------------------------------------------------------------------
                                     PAST 1 YEAR   PAST 5 YEARS   PAST 10 YEARS
<S>                                  <C>           <C>            <C>
- -------------------------------------------------------------------------------
 U.S. Government Money Market           4.71%         4.41%           4.85%
- -------------------------------------------------------------------------------
 Lipper U.S. Government Money
 Market Funds Index(1)                  4.95%         4.79%           5.19%
- -------------------------------------------------------------------------------
</TABLE>
    
 
   
1    The Lipper U.S. Government Money Market Funds Index is an equally-weighted
     performance index of the largest qualifying funds (based on net assets) in
     the Lipper U.S. Government Money Market Funds objective. The index, which
     is adjusted for capital gains distributions and income dividends, is
     unmanaged and should not be considered an investment. There are currently
     30 funds represented in the index.
 
                                                                               3
    
<PAGE>
(SIDEBAR)
ANNUAL FUND
OPERATING EXPENSES
THESE EXPENSES ARE DEDUCTED FROM THE FUND'S ASSETS AND ARE BASED ON EXPENSES
PAID FOR THE FISCAL YEAR ENDED JANUARY 31, 1999.
(END SIDEBAR)
 
ICON  FEES AND EXPENSES
- --------------------------------------------------------------------------------
   
           The Fund is a no-load fund. The Fund does not impose any sales
           charges and does not impose account or exchange fees. The table below
           briefly describes the fees and expenses that you may pay if you buy
           and hold shares of the Fund.
    
 
   
<TABLE>
<S>                                                           <C>
 ANNUAL FUND OPERATING EXPENSES
- -----------------------------------------------------------------------
 Management Fee                                                 0.46%
- -----------------------------------------------------------------------
 Distribution and service (12b-1) fees                          0.10%
- -----------------------------------------------------------------------
 Other expenses                                                 0.38%
- -----------------------------------------------------------------------
 Total annual Fund operating expenses                           0.94%
- -----------------------------------------------------------------------
</TABLE>
    
 
           EXAMPLE
   
           This example is intended to help you compare the cost of investing in
           the Fund with the cost of investing in other mutual funds.
    
 
   
           The example assumes that you invest $10,000 in the Fund, your
           investment has a 5% return each year, and the Fund's operating
           expenses remain the same. Although your actual costs may be higher or
           lower, the table below shows your costs at the end of each period
           based on these assumptions.
    
 
   
<TABLE>
<CAPTION>
- ----------------------------------------------------------
                 1 YEAR    3 YEARS    5 YEARS    10 YEARS
<S>              <C>       <C>        <C>        <C>
- ----------------------------------------------------------
                   $ 96      $300       $520       $1,155
- ----------------------------------------------------------
</TABLE>
    
 
4
<PAGE>
   
(SIDEBAR)
MORGAN STANLEY DEAN WITTER ADVISORS INC.
THE INVESTMENT MANAGER IS WIDELY RECOGNIZED AS A LEADER IN THE MUTUAL FUND
INDUSTRY AND TOGETHER WITH MORGAN STANLEY DEAN WITTER SERVICES COMPANY INC., ITS
WHOLLY-OWNED SUBSIDIARY, HAS MORE THAN $126.2 BILLION IN ASSETS UNDER MANAGEMENT
OR ADMINISTRATION AS OF FEBRUARY 28, 1999.
    
(END SIDEBAR)
 
ICON  FUND MANAGEMENT
- --------------------------------------------------------------------------------
             The Fund has retained the Investment Manager -- Morgan Stanley Dean
             Witter Advisors Inc. -- to provide administrative services, manage
             its business affairs and invest its assets, including the placing
             of orders for the purchase and sale of portfolio securities. The
             Investment Manager is a wholly-owned subsidiary of Morgan Stanley
             Dean Witter & Co., a preeminent global financial services firm that
             maintains leading market positions in each of its three primary
             businesses: securities, asset management and credit services. Its
             main business office is located at Two World Trade Center, New
             York, NY 10048.
 
   
             The Fund pays the Investment Manager a monthly management fee as
             full compensation for the services and facilities furnished to the
             Fund, and for Fund expenses assumed by the Investment Manager. The
             fee is based on the Fund's average daily net assets. For the fiscal
             year ended January 31, 1999 the Fund accrued total compensation to
             the Investment Manager amounting to 0.46% of the Fund's average
             daily net assets.
    
 
                                                                               5
<PAGE>
   
(SIDEBAR)
CONTACTING A FINANCIAL ADVISOR
IF YOU ARE NEW TO THE MORGAN STANLEY DEAN WITTER FAMILY OF FUNDS AND WOULD LIKE
TO CONTACT A FINANCIAL ADVISOR, CALL (800) THE-DEAN FOR THE TELEPHONE NUMBER OF
THE MORGAN STANLEY DEAN WITTER OFFICE NEAREST YOU.
    
YOU MAY ALSO ACCESS OUR OFFICE LOCATOR ON OUR INTERNET SITE AT:
WWW.DEANWITTER.COM/FUNDS
(END SIDEBAR)
 
SHAREHOLDER INFORMATION
 
ICON  PRICING FUND SHARES
- --------------------------------------------------------------------------------
           The price of Fund shares, called "net asset value," is based on the
           amortized cost of the Fund's portfolio securities. The amortized cost
           valuation method involves valuing a debt obligation in reference to
           its cost, rather than market forces.
 
   
           The net asset value per share of the Fund is determined once daily at
           4:00 p.m. Eastern time on each day that the New York Stock Exchange
           is open (or, on days when the New York Stock Exchange closes prior to
           4:00 p.m., at such earlier time). Shares will not be priced on days
           that the New York Stock Exchange is closed.
    
 
ICON  HOW TO BUY SHARES
- --------------------------------------------------------------------------------
   
             You may open a new account to buy Fund shares or buy additional
             Fund shares for an existing account in several ways. When you buy
             Fund shares, the shares are purchased at the next share price
             calculated after we receive your investment in proper form and
             accompanied by federal or other immediately available funds. You
             begin earning dividends the business day after the shares are
             purchased. We reserve the right to reject any order for the
             purchase of Fund shares.
    
 
   
<TABLE>
<CAPTION>
MINIMUM INVESTMENT AMOUNTS*
- --------------------------------------------------------------------
                                              MINIMUM INVESTMENT
                                          --------------------------
 INVESTMENT OPTIONS                          INITIAL     ADDITIONAL
<S>                                       <C>            <C>
- --------------------------------------------------------------------
 Regular Accounts:
                                          $       1,000     $  50
- --------------------------------------------------------------------
 Individual Retirement Accounts:
     Regular IRAs
                                          $       1,000     $  50
- --------------------------------------------------------------------
     Education IRAs
                                          $         500     $  50
- --------------------------------------------------------------------
 EASYINVEST -SM- (Automatically from
 your checking or savings account or
 Money Market Fund)
                                          not available     $ 100
- --------------------------------------------------------------------
</TABLE>
    
 
   
             There is no minimum investment amount if you purchase Fund shares
             through: (1) the Investment Manager's mutual fund asset allocation
             plan, (2) a program, approved by the Fund's distributor, in which
             you pay an asset-based fee for advisory, administrative and/or
             brokerage services, or (3) employer-sponsored employee benefit plan
             accounts. In addition, the Fund will waive the minimum initial
             investment for the automatic reinvestment of distributions from
             certain unit investment trusts.
    
 
6
<PAGE>
 
   
<TABLE>
<CAPTION>
 INVESTMENT
 OPTIONS            PROCEDURES
<S>                 <C>
- --------------------------------------------------------------------------------
 Contact Your       NEW ACCOUNTS AND SUBSEQUENT INVESTMENTS
 Financial Advisor  You may buy Fund shares by contacting your Morgan Stanley
                    Dean Witter Financial Advisor or other authorized financial
 ICON               representative. Your Financial Advisor will assist you,
                    step-by-step, with the procedures to invest in the Fund.
- --------------------------------------------------------------------------------
 By Mail            NEW ACCOUNTS
 ICON               To open a new account to buy Fund shares:
                    - Complete and sign the attached Application.
                    - Make out a check for the investment amount to: Morgan
                      Stanley Dean Witter U.S. Government Money Market Trust.
                    - Mail the Application and check to Morgan Stanley Dean
                      Witter Trust FSB at P.O. Box 1040, Jersey City, New Jersey
                      07303.
                    ------------------------------------------------------------
                    SUBSEQUENT INVESTMENTS
                    To buy additional shares for an existing Fund account:
                    - Write a "letter of instruction" to the Fund specifying the
                      name(s) on the account, the account number and the social
                      security or tax identification number, and the additional
                      investment amount. The letter must be signed by the
                      account owner(s).
                    - Make out a check for the investment amount to: Morgan
                      Stanley Dean Witter U.S. Government Money Market Trust.
                    - Mail the letter and check to Morgan Stanley Dean Witter
                      Trust FSB at the same address as for new accounts.
- --------------------------------------------------------------------------------
 By wire            NEW ACCOUNTS
 ICON               To open a new account to buy Fund shares:
                    - Mail the attached Application, completed and signed, to
                      Morgan Stanley Dean Witter Trust FSB at P.O. Box 1040,
                      Jersey City, New Jersey 07303.
                    - Before sending instructions by wire, call us at (800)
                      869-NEWS advising us of your purchase and to confirm we
                      have received your Application.
                    - Wire the instructions specifying the name of the Fund and
                      your account number, along with the additional investment
                      amount, to The Bank of New York, for credit to the account
                      of "Morgan Stanley Dean Witter Trust FSB, Harborside
                      Financial Center, Plaza Two, Jersey City, New Jersey
                      07303, Account No. 8900188413."
                    (When you buy Fund shares, wire purchase instructions
                    received by Morgan Stanley Dean Witter Trust FSB prior to
                    12:00 noon Eastern time are normally effective that day and
                    wire purchase instructions received after 12:00 noon are
                    normally effective the next business day.)
                    ------------------------------------------------------------
                    SUBSEQUENT INVESTMENTS
                    To buy additional shares for an existing Fund account:
                    - Before sending instructions by wire, call us at (800)
                      869-NEWS advising us of your purchase.
                    - Wire the instructions specifying the name of the Fund and
                      your account number, along with the investment amount, to
                      The Bank of New York, for credit to the account of Morgan
                      Stanley Dean Witter Trust FSB in the same manner as
                      opening an account.
                    (Also, when you buy additional Fund shares, wire purchase
                    instructions received by Morgan Stanley Dean Witter Trust
                    FSB prior to 12:00 noon Eastern time are normally effective
                    that day and wire purchase instructions received after 12:00
                    noon are normally effective the next business day.)
- --------------------------------------------------------------------------------
 EASYINVEST -SM-    NEW ACCOUNTS
 (Automatically     This program is not available to open a new Fund account or
 from your          a new account of another Money Market Fund.
 checking or        ------------------------------------------------------------
 savings            SUBSEQUENT INVESTMENTS
 account)           EASYINVEST-SM- A purchase plan that allows you to transfer
                    money automatically from your checking or savings account on
                    a semi-monthly, monthly or quarterly basis. Contact your
                    Morgan Stanley Dean Witter Financial
ICON
                    Advisor for further information about this service.
- --------------------------------------------------------------------------------
</TABLE>
    
 
                                                                               7
<PAGE>

           ADDITIONAL PURCHASE INFORMATION. If you are a customer of Dean Witter
           Reynolds or another authorized dealer of Fund shares, you may upon
           request: (a) have the proceeds from the sale of listed securities
           invested in Fund shares the day after you receive the proceeds; and
           (b) pay for the purchase of certain listed securities by automatic
           sale of Fund shares that you own. In addition, if you are a customer
           of Dean Witter Reynolds or another authorized dealer of Fund shares,
           you may have cash balances in your securities account (which do not
           exceed $5,000) automatically invested in shares of the Fund on a
           weekly basis.

   
    

   
           PLAN OF DISTRIBUTION. The Fund has adopted a Plan of Distribution in
           accordance with Rule 12b-1 under the Investment Company Act of 1940.
           The Plan allows the Fund to pay distribution fees for the sale and
           distribution of these shares. It also allows the Fund to pay for
           services to shareholders. Because these fees are paid out of the
           Fund's assets on an ongoing basis, over time these fees will increase
           the cost of your investment and may cost you more than paying other
           types of sales charges.
    
 
          HOW TO EXCHANGE SHARES
- --------------------------------------------------------------------------------
   
           PERMISSIBLE FUND EXCHANGES. You may only exchange shares of the Fund
           for shares of other continuously offered Morgan Stanley Dean Witter
           Funds if the Fund shares were acquired in an exchange of shares
           initially purchased in a Multi-Class Fund or an FSC Fund (subject to
           a front-end sales charge). In that case, the shares may be
           subsequently re-exchanged for shares of the same Class of any
           Multi-Class Fund or FSC Fund or for shares of another Money Market
           Fund, No-Load Fund or Short-Term U.S. Treasury Trust. Of course, if
           an exchange is not permitted, you may sell shares of the Fund and buy
           another Fund's shares with the proceeds.
    
 
           See the inside back cover of this PROSPECTUS for each Morgan Stanley
           Dean Witter Fund's designation as a Multi-Class Fund, FSC Fund,
           No-Load Fund or Money Market Fund. If a Morgan Stanley Dean Witter
           Fund is not listed, consult the inside back cover of that Fund's
           PROSPECTUS for its designation. For purposes of exchanges, shares of
           FSC Funds are treated as Class A shares of a Multi-Class Fund.
 
           An exchange privilege account also may be maintained for you if you
           acquired Fund shares in exchange for shares of various TCW/DW Funds.
 
           The current PROSPECTUS for each Fund describes its investment
           objective(s), policies and investment minimums, and should be read
           before investing.
 
           EXCHANGE PROCEDURES. You can process an exchange by contacting your
           Morgan Stanley Dean Witter Financial Advisor or other authorized
           financial representative. Otherwise, you must forward an exchange
           privilege authorization form to the Fund's transfer agent -- Morgan
           Stanley Dean Witter Trust FSB -- and then write the transfer agent or
           call (800) 869-NEWS to place an exchange order. You can obtain an
           exchange privilege authorization form by contacting your Financial
           Advisor or other authorized financial representative or by calling
           (800) 869-NEWS.
 
           An exchange to any Morgan Stanley Dean Witter Fund (except a Money
           Market Fund) is made on the basis of the next calculated net asset
           values of the Funds involved after the
 
8
<PAGE>
           exchange instructions are accepted. When exchanging into a Money
           Market Fund, the Fund's shares are sold at their next calculated net
           asset value and the Money Market Fund's shares are purchased at their
           net asset value on the following business day.
 
           The Fund may terminate or revise the exchange privilege upon required
           notice. Certain services normally available to shareholders of Money
           Market Funds, including the check writing privilege, are not
           available for Money Market Fund shares you acquire in an exchange.
 
           TELEPHONE EXCHANGES. For your protection when calling Morgan Stanley
           Dean Witter Trust FSB, we will employ reasonable procedures to
           confirm that exchange instructions communicated over the telephone
           are genuine. These procedures may include requiring various forms of
           personal identification such as name, mailing address, social
           security or other tax identification number. Telephone instructions
           also may be recorded.
 
           Telephone instructions will be accepted if received by the Fund's
           transfer agent between 9:00 a.m. and 4:00 p.m. Eastern time, on any
           day the New York Stock Exchange is open for business. During periods
           of drastic economic or market changes, it is possible that the
           telephone exchange procedures may be difficult to implement, although
           this has not been the case with the Fund in the past.
 
           MARGIN ACCOUNTS. If you have pledged your Fund shares in a margin
           account, contact your Morgan Stanley Dean Witter Financial Advisor or
           other authorized financial representative regarding restrictions on
           the exchange of such shares.
 
           EXCHANGING SHARES OF ANOTHER FUND SUBJECT TO A CONTINGENT DEFERRED
           SALES CHARGE ("CDSC"). There are special considerations when you
           exchange shares subject to a CDSC of another Morgan Stanley Dean
           Witter Fund for shares of the Fund. When determining the length of
           time you held the shares and the corresponding CDSC rate, any period
           (starting at the end of the month) during which you held shares of
           the Fund WILL NOT BE COUNTED. Thus, in effect the "holding period"
           for purposes of calculating the CDSC is frozen upon exchanging into
           the Fund. Nevertheless, if shares subject to a CDSC are exchanged for
           shares of the Fund, you will receive a credit when you sell the
           shares equal to the distribution (12b-1) fees, if any, you paid on
           those shares while in the Fund up to the amount of any applicable
           CDSC. See the PROSPECTUS of the Fund that charges the CDSC for more
           details.
 
           FREQUENT EXCHANGES. A pattern of frequent exchanges may result in the
           Fund limiting or prohibiting, at its discretion, additional purchases
           and/or exchanges. The Fund will notify you in advance of limiting
           your exchange privileges.
 
           For further information regarding exchange privileges, you should
           contact your Morgan Stanley Dean Witter Financial Advisor or call
           (800) 869-NEWS.
 
                                                                               9
<PAGE>
   
(SIDEBAR)
SYSTEMATIC
WITHDRAWAL PLAN
THIS PLAN ALLOWS YOU TO WITHDRAW MONEY AUTOMATICALLY FROM YOUR FUND ACCOUNT AT
REGULAR INTERVALS. CONTACT YOUR MORGAN STANLEY DEAN WITTER FINANCIAL ADVISOR FOR
MORE DETAILS.
    
(END SIDEBAR)
 
ICON  HOW TO SELL SHARES
- --------------------------------------------------------------------------------
   
           You can sell some or all of your Fund shares at any time. Your shares
           will be sold at the next share price calculated after we receive your
           order to sell as described below.
    
 
<TABLE>
<CAPTION>
 OPTIONS            PROCEDURES
<S>                 <C>
- --------------------------------------------------------------------------------
 Contact your       To sell your shares, simply call your Morgan Stanley Dean
 Financial Advisor  Witter Financial Advisor or other authorized financial
 ICON               representative.
                    ------------------------------------------------------------
                    Payment will be sent to the address to which the account is
                    registered or deposited in your brokerage account.
- --------------------------------------------------------------------------------
 Check-writing      You may order a supply of blank checks by requesting them on
 Option             the investment application or by contacting your Morgan
 ICON               Stanley Dean Witter Financial Advisor.
                    ------------------------------------------------------------
                    Checks may be written in any amount not less than $500. You
                    must sign checks exactly as their shares are registered. If
                    the account is a joint account, the check may contain one
                    signature unless the joint owners have specified on an
                    investment application that all owners are required to sign
                    checks.
                    ------------------------------------------------------------
                    Payment of check proceeds normally will be made on the next
                    business day after we receive your check in proper form.
                    Shares purchased by check (including a certified or bank
                    cashier's check) are not normally available to cover
                    redemption checks until fifteen days after Morgan Stanley
                    Dean Witter Trust FSB receives the check used for
                    investment. A check will not be honored in an amount
                    exceeding the value of the account at the time the check is
                    presented for payment.
- --------------------------------------------------------------------------------
 Systematic         If your investment in all of the Morgan Stanley Dean Witter
 Withdrawal Plan    Family of Funds has a total market value of at least
 ICON               $10,000, you may elect to withdraw amounts of $25 or more,
                    or in any whole percentage of a Fund's balance (provided the
                    amount is at least $25), on a monthly, quarterly,
                    semi-annual or annual basis, from any Fund with a balance of
                    at least $1,000. Each time you add a Fund to the plan, you
                    must meet the plan requirements.
                    ------------------------------------------------------------
                    To sign up for the Systematic Withdrawal Plan, contact your
                    Morgan Stanley Dean Witter Financial Advisor or call (800)
                    869-NEWS. You may terminate or suspend your plan at any
                    time. Please remember that withdrawals from the plan are
                    sales of shares, not Fund "distributions," and ultimately
                    may exhaust your account balance. The Fund may terminate or
                    revise the plan at any time.
                    ------------------------------------------------------------
                    When you sell Fund shares through the Systematic Withdrawal
                    Plan, the shares may be subject to a contingent deferred
                    sales charge ("CDSC") if they were obtained in exchange for
                    shares subject to a CDSC of another Morgan Stanley Dean
                    Witter Fund. The CDSC, however, will be waived in an amount
                    up to 12% annually of the Fund's value, although Fund shares
                    with no CDSC will be sold first, followed by those with the
                    lowest CDSC. As such, the waiver benefit will be reduced by
                    the amount of your shares that are not subject to a CDSC.
                    See the PROSPECTUS of the Fund that charges the CDSC for
                    more details.
- --------------------------------------------------------------------------------
</TABLE>
 
10
<PAGE>
 
   
<TABLE>
<CAPTION>
 OPTIONS            PROCEDURES
<S>                 <C>
- --------------------------------------------------------------------------------
 By Letter          You may also sell your shares by writing a "letter of
 ICON               instruction" that includes:
                    - your account number;
                    - the dollar amount or the number of shares you wish to
                      sell; and
                    - the signature of each owner as it appears on the account.
                    ------------------------------------------------------------
                    If you are requesting payment to anyone other than the
                    registered owner(s) or that payment be sent to any address
                    other than the address of the registered owner(s) or
                    pre-designated bank account, you will need a signature
                    guarantee. You can obtain a signature guarantee from an
                    eligible guarantor acceptable to Morgan Stanley Dean Witter
                    Trust FSB. (You should contact Morgan Stanley Dean Witter
                    Trust FSB at (800)869-NEWS for a determination as to whether
                    a particular institution is an eligible guarantor.) A notary
                    public CANNOT provide a signature guarantee. Additional
                    documentation may be required for shares held by a
                    corporation, partnership, trustee or executor.
                    ------------------------------------------------------------
                    Mail the letter to Morgan Stanley Dean Witter Trust FSB at
                    P.O. Box 983, Jersey City, NJ 07303.
                    ------------------------------------------------------------
                    A check will be mailed to the name(s) and address in which
                    the account is registered, or otherwise according to your
                    instructions.
- --------------------------------------------------------------------------------
 By Telephone or    You may also sell your shares by calling Morgan Stanley Dean
 Wire               Witter Trust FSB at (800) 869-NEWS or by sending wire
 ICON               instructions to Morgan Stanley Dean Witter Trust FSB at
 ICON               Telex No. 125076. A check will be mailed to the name(s) and
                    address in which the account is registered or, for amounts
                    of $1,000 or more, you may request a wire transfer to the
                    bank account designated in the application.
- --------------------------------------------------------------------------------
</TABLE>
    
 
   
           PAYMENT FOR SOLD SHARES. After we receive your complete instructions
           to sell as described above, a check will be mailed to you within
           seven days, although we will attempt to make payment within one
           business day. Payment may also be sent to your brokerage account.
    
 
           Payment may be postponed or the right to sell your shares suspended,
           however, under unusual circumstances. If you request to sell shares
           that were recently purchased by check, payment of the sale proceeds
           may be delayed for the minimum time needed to verify that the check
           has been honored (not more than fifteen days from the time we receive
           the check).
 
           INVOLUNTARY SALES. The Fund reserves the right, on sixty days'
           notice, to sell the shares of any shareholder whose shares, due to
           sales by the shareholder, have a value below $500. However, before
           the Fund sells your shares in this manner, we will notify you and
           allow you sixty days to make an additional investment in an amount
           that will increase the value of your account to at least the required
           amount before the sale is processed.
 
           MONEY MARKET FUND AUTOMATIC SALE PROCEDURES. If you maintain a
           brokerage account with Dean Witter Reynolds or another authorized
           dealer of Fund shares, you may elect to have your Fund shares
           automatically sold from your account to satisfy amounts you owe as a
           result of purchasing securities or other transactions in your
           brokerage account.
 
           If you elect to participate by notifying Dean Witter Reynolds or
           another authorized dealer of Fund shares, your brokerage account will
           be scanned each business day prior to the close of business (4:00
           p.m. Eastern time). After any cash balances in the account are
           applied, a sufficient number of Fund shares may be sold to satisfy
           any amounts you are obligated to pay to Dean Witter Reynolds or
           another authorized dealer of fund shares.
 
                                                                              11
<PAGE>
(SIDEBAR)
TARGETED DIVIDENDS-SM-
YOU MAY SELECT TO HAVE YOUR FUND DISTRIBUTIONS AUTOMATICALLY INVESTED IN ANOTHER
MORGAN STANLEY DEAN WITTER FUND THAT YOU OWN. CONTACT YOUR MORGAN STANLEY DEAN
WITTER FINANCIAL ADVISOR FOR FURTHER INFORMATION ABOUT THIS SERVICE.
(END SIDEBAR)
Sales will be effected on the business day before the date you are obligated to
make payment, and Dean Witter Reynolds or another authorized dealer of Fund
shares will receive the sale proceeds on the following day.
 
           EASYINVEST -SM- -- AUTOMATIC REDEMPTION. You may invest in shares of
           certain other Morgan Stanley Dean Witter Funds by subscribing to
           EASYINVEST -SM-, an automatic purchase plan that provides for the
           automatic investment of any amount from $100 to $5,000 in shares of
           the specified fund. Under EASYINVEST -SM-, you may direct that a
           sufficient number of shares of the Fund be automatically sold and the
           proceeds transferred to Morgan Stanley Dean Witter Trust FSB, on a
           semi-monthly, monthly or quarterly basis, for investment in shares of
           the specified fund. Sales of your Fund shares will be made on the
           business day preceding the investment date and Morgan Stanley Dean
           Witter Trust FSB will receive the proceeds for investment on the day
           following the sale date.
 
           MARGIN ACCOUNTS. Certain restrictions may apply to Fund shares
           pledged in margin accounts with Dean Witter Reynolds or another
           authorized broker-dealer of Fund shares. If you hold Fund shares in
           this manner, please contact your Morgan Stanley Dean Witter Financial
           Advisor or other authorized financial representative for more
           details.
 
ICON  DISTRIBUTIONS
- --------------------------------------------------------------------------------
   
           The Fund passes substantially all of its earnings along to its
           investors as "distributions." The Fund earns interest from
           fixed-income investments. These amounts are passed along to Fund
           shareholders as "income dividend distributions." The Fund may realize
           capital gains whenever it sells securities for a higher price than it
           paid for them. These amounts may be passed along as "capital gain
           distributions;" the Investment Manager does not anticipate that there
           will be significant capital gain distributions.
    
 
           The Fund declares income dividends, payable on each day the New York
           Stock Exchange is open for business, of all of its daily net income
           to shareholders of record as of the close of business the preceding
           business day. Capital gains, if any, are distributed periodically.
 
                            Distributions are reinvested automatically in
                            additional shares of the Fund (rounded to the last
                            1/100 of a share) and automatically credited to your
                            account unless you request in writing that
                            distributions be paid in cash. If you elect the cash
                            option, the Fund will reinvest the additional shares
                            and credit your account during the month, then
                            redeem the credited amount no later than the last
                            business day of the month, and mail a check to you
                            no later than seven business days after the end of
                            the month. No interest will accrue on uncashed
                            checks. If you wish to change how your distributions
                            are paid, your request should be received by the
                            Fund's transfer agent, Morgan Stanley Dean Witter
                            Trust FSB, at least five business days prior to the
                            record date of the distributions.
 
12
<PAGE>
ICON  TAX CONSEQUENCES
- --------------------------------------------------------------------------------
           As with any investment, you should consider how your Fund investment
           will be taxed. The tax information in this PROSPECTUS is provided as
           general information. You should consult your own tax professional
           about the tax consequences of an investment in the Fund.
 
           Unless your investment in the Fund is through a tax-deferred
           retirement account, such as a 401(k) plan or IRA, you need to be
           aware of the possible tax consequences when the Fund makes
           distributions.
 
           Your distributions are normally subject to federal and state income
           tax when they are paid, whether you take them in cash or reinvest
           them in Fund shares. A distribution also may be subject to local
           income tax. Any income dividend distributions and any short-term
           capital gain distributions are taxable to you as ordinary income. Any
           long-term capital gain distributions are taxable as long-term capital
           gains, no matter how long you have owned shares in the Fund.
 
           Every January, you will be sent a statement (IRS Form 1099-DIV)
           showing the taxable distributions paid to you in the previous year.
           The statement provides full information on your dividends and capital
           gains for tax purposes.
 

           When you open your Fund account, you should provide your social
           security or tax identification number on your investment application.
           By providing this information, you will avoid being subject to a
           federal backup withholding tax of 31% on taxable distributions and
           sale proceeds. Any withheld amount would be sent to the IRS as an
           advance tax payment.
   
    
                                                                              13
<PAGE>
FINANCIAL HIGHLIGHTS
 
The financial highlights table is intended to help you understand the Fund's
financial performance for the past 5 fiscal years of the Fund. Certain
information reflects financial results for a single Fund share. The total
returns in the table represent the rate an investor would have earned or lost on
an investment in the Fund (assuming reinvestment of all dividends and
distributions).
 
   
This information has been audited by PricewaterhouseCoopers LLP, whose report,
along with the Fund's financial statements, is included in this PROSPECTUS.
    
 
   
<TABLE>
<CAPTION>
 YEARS ENDED JANUARY 31                                        1999    1998    1997    1996    1995
<S>                                                           <C>     <C>     <C>     <C>     <C>
- ----------------------------------------------------------------------------------------------------
 
 SELECTED PER-SHARE DATA
- ----------------------------------------------------------------------------------------------------
 Net asset value, beginning of period                         $ 1.00  $ 1.00  $ 1.00  $ 1.00  $ 1.00
                                                              ------  ------  ------  ------  ------
    Net investment income                                      0.045   0.046   0.043   0.049   0.034
- ----------------------------------------------------------------------------------------------------
 LESS DIVIDENDS
    Net investment income                                     (0.045) (0.046) (0.043) (0.049) (0.034)
- ----------------------------------------------------------------------------------------------------
 Net asset value, end of period                               $ 1.00  $ 1.00  $ 1.00  $ 1.00  $ 1.00
- ----------------------------------------------------------------------------------------------------
 
 Total Return                                                   4.63%   4.67%   4.41%   5.00%   3.47%
- ----------------------------------------------------------------------------------------------------
 
 RATIOS TO AVERAGE NET ASSETS
- ----------------------------------------------------------------------------------------------------
 Expenses                                                       0.94%   1.02%   1.11%   1.09%   1.08%
- ----------------------------------------------------------------------------------------------------
 Net investment income                                          4.50%   4.53%   4.29%   4.86%   3.38%
- ----------------------------------------------------------------------------------------------------
 
 SUPPLEMENTAL DATA
- ----------------------------------------------------------------------------------------------------
 Net assets, end of period, in millions                       $1,017  $  891  $  927  $  903  $  809
- ----------------------------------------------------------------------------------------------------
</TABLE>
    
 
                       SEE NOTES TO FINANCIAL STATEMENTS
 
14
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
PORTFOLIO OF INVESTMENTS JANUARY 31, 1999
 
<TABLE>
<CAPTION>
                                                                                ANNUALIZED
PRINCIPAL                           DESCRIPTION                                    YIELD
AMOUNT IN                               AND                                     ON DATE OF
THOUSANDS                          MATURITY DATE                                 PURCHASE             VALUE
- ----------------------------------------------------------------------------------------------------------------
<C>        <S>                                                             <C>                    <C>
           U.S. GOVERNMENT AGENCIES (99.8%)
$126,717   Federal Farm Credit Bank
             02/05/99-07/08/99...........................................       4.72-5.52%        $  125,600,113
 451,331   Federal Home Loan Banks
             02/01/99-07/09/99...........................................        4.62-5.50           448,400,160
 261,524   Federal Home Loan Mortgage Corp. 02/16/99-06/18/99............        4.68-5.10           259,511,674
 173,221   Federal National Mortgage Assoc. 02/02/99-06/10/99............        4.72-5.06           171,818,926
  10,000   Tennessee Valley Authority 03/22/99...........................          4.81                9,932,567
                                                                                                  --------------
 
           TOTAL U.S. GOVERNMENT AGENCIES
           (AMORTIZED COST $1,015,263,440)......................................................   1,015,263,440
                                                                                                  --------------
 
           U.S. GOVERNMENT OBLIGATION (0.7%)
   7,000   U.S. Treasury Bill 03/04/99
             (AMORTIZED COST $6,968,205).................................          5.09                6,968,205
                                                                                                  --------------
 
           REPURCHASE AGREEMENT (0.2%)
   2,085   The Bank of New York due 02/01/99 (dated 01/29/99; proceeds
             $2,085,454) (a) (IDENTIFIED COST $2,084,639)................          4.688               2,084,639
                                                                                                  --------------
</TABLE>
 
<TABLE>
<S>                                                                                       <C>     <C>
TOTAL INVESTMENTS
(IDENTIFIED COST $1,024,316,284) (B)....................................................  100.7 %   1,024,316,284
 
LIABILITIES IN EXCESS OF CASH AND OTHER ASSETS..........................................   (0.7)       (6,851,521)
                                                                                          ------  ---------------
 
NET ASSETS..............................................................................  100.0 % $ 1,017,464,763
                                                                                          ------  ---------------
                                                                                          ------  ---------------
</TABLE>
 
- ---------------------
 
(a)  Collateralized by $1,748,626 U.S. Treasury Bond 6.625% due 02/15/27 valued
     at $2,126,332.
(b)  Cost is the same for federal income tax purposes.
 
                       SEE NOTES TO FINANCIAL STATEMENTS
 
                                                                              15
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
FINANCIAL STATEMENTS
 
STATEMENT OF ASSETS AND LIABILITIES
JANUARY 31, 1999
 
<TABLE>
<S>                                                                                           <C>
ASSETS:
Investments in securities, at value
  (identified cost $1,024,316,284)..........................................................  $1,024,316,284
Cash........................................................................................          90,001
Receivable for shares of beneficial interest sold...........................................         328,520
Prepaid expenses and other assets...........................................................          36,226
                                                                                              --------------
 
     TOTAL ASSETS...........................................................................   1,024,771,031
                                                                                              --------------
 
LIABILITIES:
Payable for:
    Shares of beneficial interest repurchased...............................................       6,555,859
    Investment management fee...............................................................         354,608
    Plan of distribution fee................................................................          78,679
Accrued expenses............................................................................         317,122
                                                                                              --------------
 
     TOTAL LIABILITIES......................................................................       7,306,268
                                                                                              --------------
 
     NET ASSETS.............................................................................  $1,017,464,763
                                                                                              --------------
                                                                                              --------------
 
COMPOSITION OF NET ASSETS:
Paid-in-capital.............................................................................  $1,017,463,124
Accumulated undistributed net investment income.............................................           1,639
                                                                                              --------------
 
     NET ASSETS.............................................................................  $1,017,464,763
                                                                                              --------------
                                                                                              --------------
 
NET ASSET VALUE PER SHARE,
  1,017,463,124 SHARES OUTSTANDING (UNLIMITED SHARES AUTHORIZED OF $.01 PAR VALUE)..........           $1.00
                                                                                              --------------
                                                                                              --------------
</TABLE>
 
                       SEE NOTES TO FINANCIAL STATEMENTS
 
16
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
FINANCIAL STATEMENTS, CONTINUED
 
STATEMENT OF OPERATIONS
FOR THE YEAR ENDED JANUARY 31, 1999
 
<TABLE>
<S>                                                                                              <C>
NET INVESTMENT INCOME:
 
INTEREST INCOME................................................................................  $50,615,622
                                                                                                 -----------
 
EXPENSES
Investment management fee......................................................................    4,236,205
Transfer agent fees and expenses...............................................................    3,029,492
Plan of distribution fee.......................................................................      903,926
Registration fees..............................................................................      243,033
Shareholder reports and notices................................................................      213,606
Custodian fees.................................................................................       59,794
Professional fees..............................................................................       52,052
Trustees' fees and expenses....................................................................       17,114
Other..........................................................................................       11,421
                                                                                                 -----------
 
     TOTAL EXPENSES............................................................................    8,766,643
                                                                                                 -----------
 
     NET INVESTMENT INCOME.....................................................................   41,848,979
 
     NET REALIZED GAIN.........................................................................       40,360
                                                                                                 -----------
 
NET INCREASE...................................................................................  $41,889,339
                                                                                                 -----------
                                                                                                 -----------
</TABLE>
 
                       SEE NOTES TO FINANCIAL STATEMENTS
 
                                                                              17
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
FINANCIAL STATEMENTS, CONTINUED
 
STATEMENT OF CHANGES IN NET ASSETS
 
<TABLE>
<CAPTION>
                                                                            FOR THE YEAR      FOR THE YEAR
                                                                               ENDED             ENDED
                                                                          JANUARY 31, 1999  JANUARY 31, 1998
- ------------------------------------------------------------------------------------------------------------
<S>                                                                       <C>               <C>
 
INCREASE (DECREASE) IN NET ASSETS:
 
OPERATIONS:
Net investment income...................................................  $     41,848,979  $     40,709,335
Net realized gain.......................................................            40,360         --
                                                                          ----------------  ----------------
 
     NET INCREASE.......................................................        41,889,339        40,709,335
                                                                          ----------------  ----------------
 
DIVIDENDS AND DISTRIBUTIONS TO SHAREHOLDERS FROM:
Net investment income...................................................       (41,849,500)      (40,709,121)
Net realized gain.......................................................           (40,360)        --
                                                                          ----------------  ----------------
 
     TOTAL DIVIDENDS AND DISTRIBUTIONS..................................       (41,889,860)      (40,709,121)
                                                                          ----------------  ----------------
Net increase (decrease) from transactions in shares of beneficial
  interest..............................................................       126,893,998       (36,513,549)
                                                                          ----------------  ----------------
 
     NET INCREASE (DECREASE)............................................       126,893,477       (36,513,335)
 
NET ASSETS:
Beginning of period.....................................................       890,571,286       927,084,621
                                                                          ----------------  ----------------
 
     END OF PERIOD
    (INCLUDING UNDISTRIBUTED NET INVESTMENT INCOME OF $1,639 AND $2,160,
    RESPECTIVELY).......................................................  $  1,017,464,763  $    890,571,286
                                                                          ----------------  ----------------
                                                                          ----------------  ----------------
</TABLE>
 
                       SEE NOTES TO FINANCIAL STATEMENTS
 
18
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
NOTES TO FINANCIAL STATEMENTS JANUARY 31, 1999
 
1. ORGANIZATION AND ACCOUNTING POLICIES
 
Morgan Stanley Dean Witter U.S. Government Money Market Trust (the "Trust"),
formerly Dean Witter U.S. Government Money Market Trust, is registered under the
Investment Company Act of 1940, as amended (the "Act"), as a diversified,
open-end management investment company. The Trust's investment objectives are
security of principal, high current income and liquidity. The Trust was
organized as a Massachusetts business trust on November 18, 1981 and commenced
operations on February 17, 1982.
 
The preparation of financial statements in accordance with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts and disclosures. Actual results could differ from
those estimates.
 
The following is a summary of significant accounting policies:
 
A. VALUATION OF INVESTMENTS -- Portfolio securities are valued at amortized
cost, which approximates market value.
 
B. ACCOUNTING FOR INVESTMENTS -- Security transactions are accounted for on the
trade date (date the order to buy or sell is executed). Realized gains and
losses on security transactions are determined by the identified cost method.
Premiums are amortized and discounts are accreted over the life of the
respective securities.
 
C. FEDERAL INCOME TAX STATUS -- It is the Trust's policy to comply with the
requirements of the Internal Revenue Code applicable to regulated investment
companies and to distribute all of its taxable income to its shareholders.
Accordingly, no federal income tax provision is required.
 
D. DIVIDENDS AND DISTRIBUTIONS TO SHAREHOLDERS -- The Trust records dividends
and distributions as of the close of each business day.
 
2. INVESTMENT MANAGEMENT AGREEMENT
 
Pursuant to an Investment Management Agreement with Morgan Stanley Dean Witter
Advisors Inc. (the "Investment Manager"), formerly Dean Witter InterCapital
Inc., the Trust pays the Investment Manager a management fee, accrued daily and
payable monthly, by applying the following annual rates to the net assets of the
Trust determined as of the close of each business day: 0.50% to the portion of
the daily net assets not exceeding $500 million; 0.425% to the portion of the
daily net assets exceeding $500 million but not exceeding $750 million; 0.375%
to the portion of the daily net
 
                                                                              19
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
NOTES TO FINANCIAL STATEMENTS JANUARY 31, 1999, CONTINUED
 
assets exceeding $750 million but not exceeding $1 billion; 0.35% to the portion
of the daily net assets exceeding $1 billion but not exceeding $1.5 billion;
0.325% to the portion of the daily net assets exceeding $1.5 billion but not
exceeding $2 billion; 0.30% to the portion of the daily net assets exceeding $2
billion but not exceeding $2.5 billion; 0.275% to the portion of the daily net
assets exceeding $2.5 billion but not exceeding $3 billion; and 0.25% to the
portion of the daily net assets exceeding $3 billion.
 
Under the terms of the Agreement, the Investment Manager maintains certain of
the Trust's books and records and furnishes, at its own expense, office space,
facilities, equipment, clerical, bookkeeping and certain legal services and pays
the salaries of all personnel, including officers of the Trust who are employees
of the Investment Manager. The Investment Manager also bears the cost of
telephone services, heat, light, power and other utilities provided to the
Trust.
 
3. PLAN OF DISTRIBUTION
 
Morgan Stanley Dean Witter Distributors Inc. (the "Distributor"), an affiliate
of the Investment Manager, is the distributor of the Trust's shares and, in
accordance with a Plan of Distribution (the "Plan") pursuant to Rule 12b-1 under
the Act, finances certain expenses in connection therewith.
 
Under the Plan, the Distributor bears the expense of all promotional and
distribution related activities on behalf of the Trust, except for expenses that
the Trustees determine to reimburse, as described below. The following
activities and services may be provided by the Distributor, and other selected
broker-dealers under the Plan: (1) compensation to, and expenses of, Morgan
Stanley Dean Witter Financial Advisors and other selected broker-dealers; (2)
sales incentives and bonuses to sales representatives and to marketing personnel
in connection with promoting sales of the Trust's shares; (3) expenses incurred
in connection with promoting sales of the Trust's shares; (4) preparing and
distributing sales literature; and (5) providing advertising and promotional
activities, including direct mail solicitation and television, radio, newspaper,
magazine and other media advertisements.
 
The Trust is authorized to reimburse the Distributor for specific expenses the
Distributor incurs or plans to incur in promoting the distribution of the
Trust's shares. The amount of each monthly reimbursement payment may in no event
exceed an amount equal to a payment at the annual rate of 0.15% of the Trust's
average daily net assets during the month. Expenses incurred by the Distributor
pursuant to the Plan in any fiscal year will not be reimbursed by the Trust
through payments accrued in any subsequent fiscal year. For the year ended
January 31, 1999, the distribution fee was accrued at the annual rate of 0.10%.
 
20
<PAGE>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
NOTES TO FINANCIAL STATEMENTS JANUARY 31, 1999, CONTINUED
 
4. SECURITY TRANSACTIONS AND TRANSACTIONS WITH AFFILIATES
 
The cost of purchases and proceeds from sales/maturities of portfolio securities
for the year ended January 31, 1999 aggregated $12,774,924,363 and
$12,697,076,883, respectively.
 
Morgan Stanley Dean Witter Trust FSB, an affiliate of the Investment Manager and
Distributor, is the Trust's transfer agent. At January 31, 1999, the Trust had
transfer agent fees and expenses payable of approximately $152,800.
 
The Trust has an unfunded noncontributory defined benefit pension plan covering
all independent Trustees of the Trust who will have served as independent
Trustees for at least five years at the time of retirement. Benefits under this
plan are based on years of service and compensation during the last five years
of service. Aggregate pension costs for the year ended January 31, 1999 included
in Trustees' fees and expenses in the Statement of Operations amounted to
$6,203. At January 31, 1999, the Trust had an accrued pension liability of
$50,731 which is included in accrued expenses in the Statement of Assets and
Liabilities.
 
5. SHARES OF BENEFICIAL INTEREST
 
Transactions in shares of beneficial interest, at $1.00 per share, were as
follows:
 
<TABLE>
<CAPTION>
                                                                     FOR THE YEAR        FOR THE YEAR
                                                                         ENDED               ENDED
                                                                   JANUARY 31, 1999    JANUARY 31, 1998
                                                                   -----------------   -----------------
<S>                                                                <C>                 <C>
Shares sold......................................................      2,239,344,299       2,013,452,444
Shares issued in reinvestment of dividends.......................         41,717,140          40,560,689
Acquisition of Dean Witter Retirement Series -- U.S. Government
 Money Market....................................................            837,211          --
                                                                   -----------------   -----------------
                                                                       2,281,898,650       2,054,013,133
Shares repurchased...............................................     (2,155,004,652)     (2,090,526,682)
                                                                   -----------------   -----------------
Net increase (decrease)..........................................        126,893,998         (36,513,549)
                                                                   -----------------   -----------------
                                                                   -----------------   -----------------
</TABLE>
 
6. ACQUISITION OF DEAN WITTER RETIREMENT SERIES -- U.S. GOVERNMENT MONEY MARKET
SERIES
 
As of the close of business on September 11, 1998, the Trust acquired all the
net assets of Dean Witter Retirement Series -- U.S. Government Money Market
Series ("Retirement U.S. Government") pursuant to a plan of reorganization
approved by shareholders of Retirement U.S. Government on August 19, 1998. The
acquisition was accomplished by a tax-free exchange of 837,211 shares of the
Trust at a net asset value of $1.00 per share for 837,211 shares of Retirement
U.S. Government. The net assets of the Trust and Retirement U.S. Government
immediately before the acquisition were $942,511,862 and $837,211, respectively.
Immediately after the acquisition, the combined net assets of the Trust amounted
to $943,349,073.
 
                                                                              21
<PAGE>
 
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT
MONEY MARKET TRUST
REPORT OF INDEPENDENT ACCOUNTANTS
 
TO THE SHAREHOLDERS AND TRUSTEES
OF MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
 
In our opinion, the accompanying statement of assets and liabilities, including
the portfolio of investments, and the related statements of operations and of
changes in net assets and the financial highlights (appearing in the "Financial
Highlights" table on page 14 of this Prospectus) present fairly, in all material
respects, the financial position of Morgan Stanley Dean Witter U.S. Government
Money Market Trust (the "Trust") formerly Dean Witter U.S. Government Money
Market Trust, at January 31, 1999, the results of its operations for the year
then ended, the changes in its net assets for each of the two years in the
period then ended and the financial highlights for each of the five years in the
period then ended, in conformity with generally accepted accounting principles.
These financial statements and financial highlights (hereafter referred to as
"financial statements") are the responsibility of the Trust's management; our
responsibility is to express an opinion on these financial statements based on
our audits. We conducted our audits of these financial statements in accordance
with generally accepted auditing standards which require that we plan and
perform the audit to obtain reasonable assurance about whether the financial
statements are free of material misstatement. An audit includes examining, on a
test basis, evidence supporting the amounts and disclosures in the financial
statements, assessing the accounting principles used and significant estimates
made by management, and evaluating the overall financial statement presentation.
We believe that our audits, which included confirmation of securities at January
31, 1999 by correspondence with the custodian, provide a reasonable basis for
the opinion expressed above.
 
Pricewaterhouse Coopers LLP
1177 AVENUE OF THE AMERICAS
NEW YORK, NEW YORK 10036
MARCH 5, 1999
 
22
<PAGE>
MORGAN STANLEY DEAN WITTER
FAMILY OF FUNDS
 
                           The Morgan Stanley Dean Witter Family of Funds offers
                           investors a wide range of investment choices. Come on
                           in and meet the family!
- --------------------------------------------------------------------------------
 GROWTH FUNDS
- ---------------------------------
 
GROWTH FUNDS
Aggressive Equity Fund
   
American Value Fund
    
Capital Growth Securities
Developing Growth Securities
Equity Fund
Growth Fund
Market Leader Trust
Mid-Cap Growth Fund
Special Value Fund
Value Fund
 
THEME FUNDS
Financial Services Trust
Health Sciences Trust
Information Fund
Natural Resource Development Securities
   
Precious Metals and Minerals Trust
    
 
GLOBAL/INTERNATIONAL FUNDS
Competitive Edge Fund - "Best Ideas" Portfolio
European Growth Fund
Fund of Funds - International Portfolio
   
Global Dividend Growth Securities
    
International SmallCap Fund
Japan Fund
Pacific Growth Fund
- --------------------------------------------------------------------------------
 GROWTH AND INCOME FUNDS
- ---------------------------------
Balanced Growth Fund
Balanced Income Fund
Convertible Securities Trust
Dividend Growth Securities
Fund of Funds - Domestic Portfolio
   
Income Builder Fund
    
   
Mid-Cap Dividend Growth Securities
    
   
S&P 500 Index Fund
    
S&P 500 Select Fund
Strategist Fund
Value-Added Market Series/Equity Portfolio
 
   
THEME FUNDS
    
   
Global Utilities Fund
    
   
Real Estate Fund
    
   
Utilities Fund
    
- --------------------------------------------------------------------------------
 INCOME FUNDS
- ---------------------------------
 
GOVERNMENT INCOME FUNDS
Federal Securities Trust
Short-Term U.S. Treasury Trust
U.S. Government Securities Trust
 
DIVERSIFIED INCOME FUNDS
Diversified Income Trust
 
CORPORATE INCOME FUNDS
High Yield Securities
Intermediate Income Securities
   
Short-Term Bond Fund (NL)
    
 
GLOBAL INCOME FUNDS
World Wide Income Trust
 
TAX-FREE INCOME FUNDS
California Tax-Free Income Fund
Hawaii Municipal Trust (FSC)
Limited Term Municipal Trust (NL)
Multi-State Municipal Series Trust (FSC)
New York Tax-Free Income Fund
Tax-Exempt Securities Trust
- --------------------------------------------------------------------------------
 MONEY MARKET FUNDS
- ---------------------------------
 
TAXABLE MONEY MARKET FUNDS
Liquid Asset Fund (MM)
U.S. Government Money Market Trust (MM)
 
TAX-FREE MONEY MARKET FUNDS
California Tax-Free Daily Income Trust (MM)
N.Y. Municipal Money Market Trust (MM)
Tax-Free Daily Income Trust (MM)
 
   
There may be Funds created after this PROSPECTUS was published. Please consult
the inside front cover of a new Fund's PROSPECTUS for its designation, e.g.,
Multi-Class Fund or Money Market Fund.
    
 
   
Unless otherwise noted, each listed Morgan Stanley Dean Witter Fund, except for
Short-Term U.S. Treasury Trust, is a Multi-Class Fund. A Multi-Class Fund is a
mutual fund offering multiple Classes of shares. The other types of funds are:
NL - No-Load (Mutual) Fund; MM - Money Market Fund; FSC - A mutual fund sold
with a front-end sales charge and a distribution (12b-1) fee.
    
<PAGE>
 
  2  3  0 --
 for office use only
 
                                                                [LOGO]
APPLICATION
 
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
Send to: Morgan Stanley Dean Witter Trust FSB (the "Transfer Agent"), P.O. Box
1040, Jersey City, NJ 07303

[REMOVE APPLICATION CAREFULLY]

<TABLE>
<S>               <C>
INSTRUCTIONS        For assistance in completing this application, telephone Morgan Stanley Dean Witter Trust FSB at (800) 869-NEWS
                    (toll-free).
TO REGISTER
SHARES              1.
(please print)
                  ---------------------------------------------------------------------------------------------------------------
                                  First Name                                    Last Name
- -As joint
  tenants,
  use line          2.
  1 & 2           ---------------------------------------------------------------------------------------------------------------
                                  First Name                                    Last Name
                    (Joint tenants with rights of survivorship unless otherwise
                    specified)
                                                                                              ------------------------
                                                                                              Social Security Number
- -As custodian
  for a minor,      3.
  use lines 1 &
  3
                   ---------------------------------------------------------------------------------------------------------------
                                                                    Minor's Name
                    Under the________Uniform Gifts to Minors Act                            ---------------------------
                                                                                           Minor's Social Security Number
                    State of Residence of Minor
- -In the name of a
  corporation,      4.
  trust,
  partnership
  or other         ---------------------------------------------------------------------------------------------------------------
  institutional                       Name of Corporation, Trust (including trustee name(s)) or Other Organization
  investors, use
  line 4
                    If Trust, Date of Trust Instrument:____________                          Tax Identification
                                                                                             Number__________
ADDRESS
                   ---------------------------------------------------------------------------------------------------------------
                      City                       State                       Zip Code

TO PURCHASE
SHARES:
Minimum Initial     / / CHECK (enclosed) $__________ (Make Payable to Morgan Stanley Dean Witter U.S. Government Money Market
Investment:         Trust)
$1,000              / / WIRE*  On__________          MF*________
                    (Date)                            (Control number, this transaction)

                   ----------------------------------------------------------------------------------------------------------
                    Name of Bank                                                                        Branch
                   ----------------------------------------------------------------------------------------------------------
                    Address
                   ----------------------------------------------------------------------------------------------------------
                    Telephone Number
                    * For an initial investment made by wiring funds, obtain a control number by calling: (800) 869-NEWS
                    (toll-free).
                    Your bank should wire to:
                    Bank of New York for credit to account of Morgan Stanley Dean Witter Trust FSB

                    Account Number: 8900188413
                    Re: Morgan Stanley Dean Witter U.S. Government Money Market Trust
                    Account Of:______________________
                    (Investor's Account as Registered at the Transfer Agent)
                    Control or Account Number:______________________
                    (Assigned by Telephone)
                                                         OPTIONAL SERVICES

                    NOTE: If you are a current shareholder of Morgan Stanley Dean Witter
                    U.S. Government Money Market Trust, please indicate your fund
                    account number here.
                    [ 2 ] [ 3 ] [ 0 ]  -

DIVIDENDS           All dividends will be reinvested daily in additional shares, unless the following option is selected:
                    / / Pay income dividends by check at the end of each month.
WRITE YOUR OWN      / / Send an initial supply of checks.
CHECK               FOR JOINT ACCOUNTS:
                    / / CHECK THIS BOX IF ALL OWNERS ARE REQUIRED TO SIGN CHECKS.
</TABLE>
 
<PAGE>
 
<TABLE>
<S>               <C>
                  / /  Morgan Stanley Dean Witter Trust FSB is hereby authorized to honor telephonic or other instructions, without
PAYMENT TO           signature guarantee, from any person for the redemption of any or all shares of Morgan Stanley Dean Witter U.S.
PREDESIGNATED          Government Money Market Trust held in my (our) account provided that proceeds are transmitted only to the
BANK ACCOUNT           following bank account. (Absent its own negligence, neither Morgan Stanley Dean Witter U.S. Government Money
                       Market Trust nor Morgan Stanley Dean Witter Trust FSB (the "Transfer Agent") shall be liable for any
                       redemption caused by unauthorized instruction(s)):
Bank Account
must be in
same name as
shares are
registered        -------------------------------------------------------------------------------  ------------------------------
                  NAME & BANK ACCOUNT NUMBER                                                        BANK'S ROUTING TRANSMIT CODE
                                                                                                          (ASK YOUR BANK)
Minimum Amount:   -------------------------------------------------------------------------------
$1,000            NAME OF BANK

                  -------------------------------------------------------------------------------
                  ADDRESS OF BANK
                  (       )
                  -------------------------------------------------------------------------------
                  TELEPHONE NUMBER OF BANK
                                                              SIGNATURE AUTHORIZATION
FOR ALL ACCOUNTS  NOTE: RETAIN A COPY OF THIS DOCUMENT FOR YOUR RECORDS. ANY MODIFICATION OF THE INFORMATION BELOW WILL REQUIRE AN
                  AMENDMENT TO THIS FORM. THIS DOCUMENT IS IN FULL FORCE AND EFFECT UNTIL ANOTHER DULY EXECUTED FORM IS RECEIVED BY
                  THE TRANSFER AGENT.
                  The "Transfer Agent" is hereby authorized to act as agent for the registered owner of shares of Morgan Stanley
                  Dean Witter U.S. Government Money Market Trust (the "Fund") in effecting redemptions of shares and is authorized
                  to recognize the signature(s) below in payment of funds resulting from such redemptions on behalf of the
                  registered owners of such shares. The Transfer Agent shall be liable only for its own negligence and not for
                  default or negligence of its correspondents, or for losses in transit. The Fund shall not be liable for any
                  default or negligence of the Transfer Agent.
                  I (we) certify to my (our) legal capacity, or the capacity of the investor named above, to invest in and redeem
                  shares of, and I (we) acknowledge receipt of a current prospectus of, Morgan Stanley Dean Witter U.S. Government
                  Money Market Trust and (we) further certify my (our) authority to sign and act for and on behalf of the investor.
                  Under penalties of perjury, I certify (1) that the number shown on this form is my correct taxpayer identification
                  number and (2) that I am not subject to backup withholding either because I have not been notified that I am
                  subject to backup withholding as a result of a failure to report all interest or dividends, or the Internal
                  Revenue Service has notified me that I am no longer subject to backup withholding. (Note: You must cross out item
                  (2) above if you have been notified by IRS that you are currently subject to backup withholding because of
                  underreporting interest or dividends on your tax return.)
                  For Individual, Joint and Custodial Accounts for Minors, Check Applicable Box:
                  / / I am a United States Citizen.                     / / I am not a United States Citizen.
                                                  SIGNATURE(S) (IF JOINT TENANTS, ALL MUST SIGN)
</TABLE>
 
<TABLE>
<S>               <C>                                                       <C>
                  ------------------------------------------------          ------------------------------------------------
                          SIGNATURE MUST BE KEPT WITHIN ABOVE AREA                  SIGNATURE MUST BE KEPT WITHIN ABOVE AREA

                  --------------------------------------------------------  --------------------------------------------------------
                          SIGNATURE MUST BE KEPT WITHIN ABOVE AREA                  SIGNATURE MUST BE KEPT WITHIN ABOVE AREA
Name(s) must be
signed
exactly the same  SIGNED THIS_______________DAY OF__________, 19____.
as shown on
lines 1 to 4 on
the reverse
side of this                                FOR CORPORATIONS, TRUSTS, PARTNERSHIPS AND OTHER ORGANIZATIONS
application
                  The following named persons are currently officers/trustees/general partners/other authorized signatories of the
                  Registered Owner, and any * of them ("Authorized Person(s)") is/are currently authorized under the applicable
                  governing document to act with full power to sell, assign or transfer securities of the the Fund for the
                  Registered Owner and to execute and deliver any instrument necessary to effectuate the authority hereby conferred:
                                         NAME/TITLE                                                SIGNATURE
</TABLE>
 
<TABLE>
<S>               <C>                                                       <C>
In addition,
complete
Section A or B    --------------------------------------------------------  --------------------------------------------------------
below.
                  --------------------------------------------------------  --------------------------------------------------------
                          SIGNATURE MUST BE KEPT WITHIN ABOVE AREA                  SIGNATURE MUST BE KEPT WITHIN ABOVE AREA

                  --------------------------------------------------------  --------------------------------------------------------
                          SIGNATURE MUST BE KEPT WITHIN ABOVE AREA                  SIGNATURE MUST BE KEPT WITHIN ABOVE AREA

                  --------------------------------------------------------  --------------------------------------------------------
                          SIGNATURE MUST BE KEPT WITHIN ABOVE AREA                  SIGNATURE MUST BE KEPT WITHIN ABOVE AREA
                  SIGNED THIS____________DAY OF____________, 19____.
                  The Transfer Agent may, without inquiry, act only upon the instruction of ANY PERSON(S) purporting to be (an)
                  Authorized Person(s) as named in the Certification Form last received by the Transfer Agent. The Transfer Agent
                  and the Fund shall not be liable for any claims, expenses (including legal fees) or losses resulting from the
                  Transfer Agent having acted upon any instruction reasonably believed genuine.
                  ------------------------------------------------------------------------------------------------------------------
                  *INSERT A NUMBER. UNLESS OTHERWISE INDICATED, THE TRANSFER AGENT MAY HONOR INSTRUCTIONS OF ANY ONE OF THE PERSONS
                   NAMED ABOVE.
</TABLE>
 
<TABLE>
<S>                   <C>
SECTION (A)           NOTE: EITHER A SIGNATURE GUARANTEE OR CORPORATE SEAL IS REQUIRED.
CORPORATIONS AND
INCORPORATED
ASSOCIATIONS ONLY.    I, ____________, Secretary of the Registered Owner, do hereby certify that at a meeting on
SIGN ABOVE AND COM-   ____________ at which a quorum was present throughout, the Board of Directors of the
PLETE THIS            corporation/the officers of the association duly adopted a resolution, which is in full force and
SECTION               effect and in accordance with the Registered Owner's charter and by-laws, which resolution did the
                      following: (1) empowered the above-named Authorized Person(s) to effect securities transactions
                      for the Registered Owner on the terms described above; (2) authorized the Secretary to certify,
                      from time to time, the names and titles of the officers of the Registered Owner and to notify the
                      Transfer Agent when changes in office occur; and (3) authorized the Secretary to certify that such
                      a resolution has been duly adopted and will remain in full force and effect until the Transfer
                      Agent receives a duly executed amendment to the Certification Form.
SIGNATURE
GUARANTEE**           Witness my hand on behalf of the corporation/association this ______ day of ____________, 19____.
(or Corporate Seal)
                      --------------------------------------------------------------------------------------------------
                                                                 Secretary**
                      The undersigned officer (other than the Secretary) hereby certifies that the foregoing instrument
                      has been signed by the Secretary of the
                      corporation/association.
SIGNATURE
GUARANTEE**           --------------------------------------------------------------------------------------------------
(or Corporate Seal)                  Certifying Officer of the Corporation or Incorporated Association**

SECTION (B) ALL                                    NOTE: A SIGNATURE GUARANTEE IS REQUIRED.
OTHER
INSTITUTIONAL         --------------------------------------------------------------------------------------------------
INVESTORS                                                         Certifying
SIGNATURE                                          Trustee(s)/General Partner(s)/Other(s)**
GUARANTEE**
                      --------------------------------------------------------------------------------------------------
SIGN ABOVE AND COM-                                               Certifying
PLETE THIS SECTION                                 Trustee(s)/General Partner(s)/Other(s)**
                      --------------------------------------------------------------------------------------------------
                      **SIGNATURE(S) MUST BE GUARANTEED BY AN ELIBIGLE GUARANTOR
</TABLE>

<TABLE>
<S>               <C>
DEALER            Above signature(s) guaranteed. Prospectus has been delivered by undersigned to above-named applicant(s).
(if any)
Completion by
dealer only       ----------------------------------------------------  ----------------------------------------------------
                  Firm Name                                             Office Number-Account Number at Dealer-A/E Number
                  ----------------------------------------------------  ----------------------------------------------------
                  Address                                               Account Executive's Last Name
                  ----------------------------------------------------  ----------------------------------------------------
                  City, State, Zip Code                                 Branch Office
</TABLE>
 
- -Registered Trademark- 1999 Morgan Stanley Dean Witter Distributors Inc.
<PAGE>
                                                     PROSPECTUS - MARCH 29, 1999
 
   
Additional information about the Fund's investments is available in the Fund's
ANNUAL AND SEMI-ANNUAL REPORTS TO SHAREHOLDERS (the current annual report is
included in this PROSPECTUS). The Fund's STATEMENT OF ADDITIONAL INFORMATION
also provides additional information about the Fund. The STATEMENT OF ADDITIONAL
INFORMATION is incorporated herein by reference (legally is part of this
PROSPECTUS). For a free copy of any of these documents, to request other
information about the Fund, or to make shareholder inquiries, please call:
    
 
   
                                 (800) 869-NEWS
    
 
You also may obtain information about the Fund by calling your Morgan Stanley
Dean Witter Financial Advisor or by visiting our Internet site at:
                            www.deanwitter.com/funds
 
   
Information about the Fund (including the STATEMENT OF ADDITIONAL INFORMATION)
can be viewed and copied at the Securities and Exchange Commission's Public
Reference Room in Washington, DC. Information about the Reference Room's
operations may be obtained by calling the SEC at (800) SEC-0330. Reports and
other information about the Fund are available on the SEC's Internet site
(www.sec.gov) and copies of this information may be obtained, upon payment of a
duplicating fee, by writing the Public Reference Section of the SEC, Washington,
DC 20549-6009.
    
 
Morgan Stanley Dean Witter
                                                                 U.S. GOVERNMENT
                                                              MONEY MARKET TRUST
 
                               [BACK COVER PHOTO]
 
 TICKER SYMBOL: DWGXX
 
   
(INVESTMENT COMPANY ACT FILE NO. 811-3326)
    
<PAGE>
 
STATEMENT OF ADDITIONAL INFORMATION                           MORGAN STANLEY
MARCH 29, 1999                                                DEAN WITTER
                                                              U.S. GOVERNMENT
                                                              MONEY MARKET
                                                              TRUST
 
- --------------------------------------------------------------------------------
 
   
    This STATEMENT OF ADDITIONAL INFORMATION is not a PROSPECTUS. The PROSPECTUS
(dated March 29, 1999) for the Morgan Stanley Dean Witter U.S. Government Money
Market Trust may be obtained without charge from the Fund at its address or
telephone number listed below or from Dean Witter Reynolds at any of its branch
offices.
    
 
   
Morgan Stanley Dean Witter
U.S. Government Money Market Trust
Two World Trade Center
New York, New York 10048
(800) 869-NEWS
    
<PAGE>
TABLE OF CONTENTS
- --------------------------------------------------------------------------------
 
<TABLE>
<S>                                                                                      <C>
I. Fund History........................................................................          4
 
II. Description of the Fund and Its Investments and Risks..............................          4
 
  A. Classification....................................................................          4
 
  B. Investment Strategies and Risks...................................................          4
 
  C. Fund Policies/Investment Restrictions.............................................          6
 
III. Management of the Fund............................................................          7
 
  A. Board of Trustees.................................................................          7
 
  B. Management Information............................................................          7
 
  C. Compensation......................................................................         12
 
IV. Control Persons and Principal Holders of Securities................................         14
 
V. Investment Management and Other Services............................................         14
 
  A. Investment Manager................................................................         14
 
  B. Principal Underwriter.............................................................         15
 
  C. Services Provided by the Investment Manager and Fund Expenses Paid by Third
   Parties.............................................................................         15
 
  D. Rule 12b-1 Plan...................................................................         16
 
  E. Other Service Providers...........................................................         18
 
VI. Brokerage Allocation and Other Practices...........................................         18
 
  A. Brokerage Transactions............................................................         18
 
  B. Commissions.......................................................................         18
 
  C. Brokerage Selection...............................................................         19
 
  D. Directed Brokerage................................................................         20
 
  E. Regular Broker-Dealers............................................................         20
 
VII. Capital Stock and Other Securities................................................         20
 
VIII. Purchase, Redemption and Pricing of Shares.......................................         21
 
  A. Purchase/Redemption of Shares.....................................................         21
 
  B. Offering Price....................................................................         21
 
IX. Taxation of the Fund and Shareholders..............................................         23
 
X. Underwriters........................................................................         24
 
XI. Calculation of Performance Data....................................................         24
 
XII. Financial Statements..............................................................         25
</TABLE>
 
                                       2
<PAGE>
GLOSSARY OF SELECTED DEFINED TERMS
- --------------------------------------------------------------------------------
 
    The terms defined in this glossary are frequently used in this STATEMENT OF
ADDITIONAL INFORMATION (other terms used occasionally are defined in the text of
the document).
 
"CUSTODIAN"--The Bank of New York is the Custodian of the Fund's assets.
 
"DEAN WITTER REYNOLDS"--Dean Witter Reynolds Inc., a wholly-owned broker-dealer
subsidiary of MSDW.
 
"DISTRIBUTOR"--Morgan Stanley Dean Witter Distributors Inc., a wholly-owned
broker-dealer subsidiary of MSDW.
 
"FINANCIAL ADVISORS"--Morgan Stanley Dean Witter authorized financial services
representatives.
 
"FUND"--Morgan Stanley Dean Witter U.S. Government Money Market Trust, a
registered open-end investment company.
 
"INVESTMENT MANAGER"--Morgan Stanley Dean Witter Advisors Inc., a wholly-owned
investment advisor subsidiary of MSDW.
 
"INDEPENDENT TRUSTEES"--Trustees who are not "interested persons" (as defined by
the Investment Company Act) of the Fund.
 
"MORGAN STANLEY & CO."--Morgan Stanley & Co. Incorporated, a wholly-owned
broker-dealer subsidiary of MSDW.
 
"MORGAN STANLEY DEAN WITTER FUNDS"--Registered investment companies (i) for
which the Investment Manager serves as the investment advisor and (ii) that hold
themselves out to investors as related companies for investment and investor
services.
 
"MSDW"--Morgan Stanley Dean Witter & Co., a preeminent global financial services
firm.
 
"MSDW SERVICES COMPANY"--Morgan Stanley Dean Witter Services Company Inc., a
wholly-owned fund services subsidiary of the Investment Manager.
 
"TRANSFER AGENT"--Morgan Stanley Dean Witter Trust FSB, a wholly-owned transfer
agent subsidiary of MSDW.
 
"TRUSTEES"--The Board of Trustees of the Fund.
 
                                       3
<PAGE>
I. FUND HISTORY
- --------------------------------------------------------------------------------
 
    The Fund was organized as a Massachusetts business trust, under a
Declaration of Trust, on November 18, 1981, with the name Sears U.S. Government
Money Market Trust. On March 21, 1983, the Fund's name was changed to Dean
Witter/Sears U.S. Government Money Market Trust. On February 19, 1993, the
Fund's name was changed to Dean Witter U.S. Government Money Market Trust.
Effective June 22, 1998, the Fund's name was changed to Morgan Stanley Dean
Witter U.S. Government Money Market Trust.
 
II. DESCRIPTION OF THE FUND AND ITS INVESTMENTS AND RISKS
- --------------------------------------------------------------------------------
 
A. CLASSIFICATION
 
    The Fund is an open-end, diversified management investment company whose
investment objectives are security of principal, high current income and
liquidity.
 
B. INVESTMENT STRATEGIES AND RISKS
 
    The following discussion of the Fund's investment strategies and risks
should be read with the sections of the Fund's PROSPECTUS titled "Principal
Investment Strategies" and "Principal Risks."
 
    REPURCHASE AGREEMENTS.  The Fund may invest in repurchase agreements. When
cash may be available for only a few days, it may be invested by the Fund in
repurchase agreements until such time as it may otherwise be invested or used
for payments of obligations of the Fund. These agreements, which may be viewed
as a type of secured lending by the Fund, typically involve the acquisition by
the Fund of debt securities from a selling financial institution such as a bank,
savings and loan association or broker-dealer. The agreement provides that the
Fund will sell back to the institution, and that the institution will
repurchase, the underlying security serving as collateral at a specified price
and at a fixed time in the future, usually not more than seven days from the
date of purchase. The Fund will accrue interest from the institution until the
time when the repurchase is to occur. Although this date is deemed by the Fund
to be the maturity date of a repurchase agreement, the maturities of securities
subject to repurchase agreements are not subject to any limits.
 
    While repurchase agreements involve certain risks not associated with direct
investments in debt securities, the Fund follows procedures designed to minimize
such risks. These procedures include effecting repurchase transactions only with
large, well capitalized and well established financial institutions, whose
financial condition will be continuously monitored. In addition, the value of
the collateral underlying the repurchase agreement will always be at least equal
to the resale price which consists of the acquisition price paid to the seller
of the securities plus the accrued resale premium which is defined as the amount
specified in the repurchase agreement or the daily amortization of the
difference between the acquisition price and the resale price specified in the
repurchase agreement. Such collateral will consist entirely of securities that
are direct obligations of, or that are fully guaranteed as to principal and
interest by, the United States or any agency thereof, and/or certificates of
deposit, bankers' acceptances which are eligible for acceptance by a Federal
Reserve Bank, and, if the seller is a bank, mortgage related securities (as such
term is defined in section 3(a)(41) of the Securities Exchange Act of 1934 that,
at the time the repurchase agreement is entered into, are rated in the highest
rating category by the Requisite NRSROs (as defined under Rule 2a-7 of the
Investment Company Act of 1940). Additionally, Upon an Event of Insolvency (as
defined under Rule 2a-7) with respect to the seller, the collateral must qualify
the repurchase agreement for preferential treatment under a provision of
applicable insolvency law providing an exclusion from any automatic stay of
creditors' rights against the seller. In the event of a default or bankruptcy by
a selling financial institution, the Fund will seek to liquidate such
collateral. However, the exercising of the Fund's right to liquidate such
collateral could involve certain costs or delays and, to the extent that
proceeds from any sale upon a default of the obligation to repurchase were less
than the repurchase price, the Fund could suffer a loss. It is the current
policy of the Fund not to invest in repurchase agreements that do not mature
within seven days if any such investment, together with any other illiquid
assets held by the Fund, amount to more than 10% of its total assets. The Fund's
investments in repurchase agreements may at times be substantial when, in the
view of the Fund's investment manager, liquidity or other considerations
warrant.
 
                                       4
<PAGE>
    REVERSE REPURCHASE AGREEMENTS.  The Fund may also use reverse repurchase
agreements as part of its investment strategy. Reverse repurchase agreements
involve sales by the Fund of portfolio assets concurrently with an agreement by
the Fund to repurchase the same assets at a later date at a fixed price.
Generally, the effect of such a transaction is that the Fund can recover all or
most of the cash invested in the portfolio securities involved during the term
of the reverse repurchase agreement, while it will be able to keep the interest
income associated with those portfolio securities. Such transactions are only
advantageous if the interest cost to the Fund of the reverse repurchase
transaction is less than the cost of obtaining the cash otherwise. Opportunities
to achieve this advantage may not always be available, and the Fund intends to
use the reverse repurchase technique only when it will be to its advantage to do
so. The Fund will establish a segregated account with its custodian bank in
which it will maintain cash or cash equivalents or other portfolio securities
equal in value to its obligations in respect of reverse repurchase agreements.
Reverse repurchase agreements are considered borrowings by the Fund and for
purposes other than meeting redemptions may not exceed 5% of the Fund's total
assets.
 
    LENDING PORTFOLIO SECURITIES.  The Fund may lend its portfolio securities to
brokers, dealers and other financial institutions, provided that the loans are
callable at any time by the Fund, and are at all times secured by cash or cash
equivalents, which are maintained in a segregated account pursuant to applicable
regulations and that are equal to at least 100% of the market value, determined
daily, of the loaned securities. The advantage of these loans is that the Fund
continues to receive the income on the loaned securities while at the same time
earning interest on the cash amounts deposited as collateral, which will be
invested in short-term obligations. The Fund will not lend its portfolio
securities if such loans are not permitted by the laws or regulations of any
state in which its shares are qualified for sale and will not lend more than 10%
of the value of its total assets.
 
    As with any extensions of credit, there are risks of delay in recovery and,
in some cases, even loss of rights in the collateral should the borrower of the
securities fail financially. However, these loans of portfolio securities will
only be made to firms deemed by the Fund's management to be creditworthy and
when the income which can be earned from such loans justifies the attendant
risks. Upon termination of the loan, the borrower is required to return the
securities to the Fund. Any gain or loss in the market price during the loan
period would inure to the Fund.
 
    When voting or consent rights which accompany loaned securities pass to the
borrower, the Fund will follow the policy of calling the loaned securities, to
be delivered within one day after notice, to permit the exercise of the rights
if the matters involved would have a material effect on the Fund's investment in
the loaned securities. The Fund will pay reasonable finder's, administrative and
custodial fees in connection with a loan of its securities.
 
    WHEN-ISSUED AND DELAYED DELIVERY SECURITIES.  From time to time the Fund may
purchase securities on a when-issued or delayed delivery basis. When these
transactions are negotiated, the price is fixed at the time of the commitment,
but delivery and payment can take place a month or more after the date of
commitment. While the Fund will only purchase securities on a when-issued,
delayed delivery with the intention of acquiring the securities, the Fund may
sell the securities before the settlement date, if it is deemed advisable. The
securities so purchased or sold are subject to market fluctuation and no
interest or dividends accrue to the purchaser prior to the settlement date.
 
    At the time the Fund makes the commitment to purchase or sell securities on
a when-issued, delayed delivery, it will record the transaction and thereafter
reflect the value, each day, of such security purchased, or if a sale, the
proceeds to be received, in determining its net asset value. At the time of
delivery of the securities, their value may be more or less than the purchase or
sale price. An increase in the percentage of the Fund's assets committed to the
purchase of securities on a when-issued, delayed delivery may increase the
volatility of its net asset value. The Fund will also establish a segregated
account on the Fund's books in which it will continually maintain cash or cash
equivalents or other liquid portfolio securities equal in value to commitments
to purchase securities on a when-issued or delayed delivery basis.
 
    YEAR 2000.  The investment management services provided to the Fund by the
Investment Manager and the services provided to shareholders by the Distributor
and the Transfer Agent depend on the smooth functioning of their computer
systems. Many computer software systems in use today cannot
 
                                       5
<PAGE>
recognize the year 2000, but revert to 1900 or some other date, due to the
manner in which dates were encoded and calculated. That failure could have a
negative impact on the handling of securities trades, pricing and account
services. The Investment Manager, the Distributor and the Transfer Agent have
been actively working on necessary changes to their own computer systems to
prepare for the year 2000 and expect that their systems will be adapted before
that date, but there can be no assurance that they will be successful, or that
interaction with other non-complying computer systems will not impair their
services at that time.
 
    In addition, it is possible that the markets for securities in which the
Fund invests may be detrimentally affected by computer failures throughout the
financial services industry beginning January 1, 2000. Improperly functioning
trading systems may result in settlement problems and liquidity issues. In
addition, corporate and governmental data processing errors may result in
production problems for individual companies and overall economic uncertainties.
Earnings of individual issuers will be affected by remediation costs, which may
be substantial and may be reported inconsistently in U.S. and foreign financial
statements. Accordingly, the Fund's investments may be adversely affected.
 
C. FUND POLICIES/INVESTMENT RESTRICTIONS
 
   
    The investment objectives, policies and restrictions listed below have been
adopted by the Fund as fundamental policies. Under the Investment Company Act of
1940 (the "Investment Company Act"), a fundamental policy may not be changed
without the vote of a majority of the outstanding voting securities of the Fund.
The Investment Company Act defines a majority as the lesser of (a) 67% or more
of the shares present at a meeting of shareholders, if the holders of 50% of the
outstanding shares of the Fund are present or represented by proxy; or (b) more
than 50% of the outstanding shares of the Fund. For purposes of the following
restrictions: (i) all percentage limitations apply immediately after a purchase
or initial investment; and (ii) any subsequent change in any applicable
percentage resulting from market fluctuations or other changes in total or net
assets does not require elimination of any security from the portfolio.
    
 
   
    The Fund will:
    
 
   
         1.  Seek to provide security of principal, high current income and
    liquidity.
    
 
    The Fund may not:
 
         1.  Purchase common stocks, preferred stocks, warrants, other equity
    securities, corporate bonds, municipal bonds or industrial revenue bonds.
 
         2.  Borrow money, except from banks for temporary or emergency
    purposes, including the meeting of redemption requests which might otherwise
    require the untimely disposition of securities; or through its transactions
    in reverse repurchase agreements. Borrowing in the aggregate, including
    reverse repurchase agreements, may not exceed 20%, and borrowing for
    purposes other than meeting redemptions may not exceed 5% of the value of
    the Fund's total assets (including the amount borrowed), less liabilities
    (not including the amount borrowed) at the time the borrowing is made.
    Borrowings in excess of 5% will be repaid before additional investments are
    made.
 
         3.  Pledge, hypothecate, mortgage or otherwise encumber its assets,
    except in an amount up to 10% of the value of its net assets, but only to
    secure borrowings for temporary or emergency purposes.
 
         4.  Sell securities short or purchase securities on margin.
 
         5.  Write or purchase put or call options.
 
         6.  Underwrite the securities of other issuers or purchase restricted
    securities except insofar as the Fund may enter into any repurchase or
    reverse repurchase agreements.
 
                                       6
<PAGE>
         7.  Purchase or sell real estate, real estate investment trust
    securities, commodities or commodity contracts or oil and gas interests.
 
         8.  Make loans to others, except: (a) by the purchase of qualified debt
    obligations; (b) lending portfolio securities; and (c) by investment in
    repurchase agreements referred to above and in the Prospectus.
 
         9.  Issue senior securities as defined in the Act except insofar as the
    Fund may be deemed to have issued a senior security by reason of: (a)
    entering into any repurchase or reverse repurchase agreement; (b) borrowing
    money in accordance with restrictions described above; or (c) lending
    portfolio securities.
 
        10.  Purchase securities of other investment companies, except in
    connection with a merger, consolidation, reorganization or acquisition of
    assets.
 
        11.  Lend its portfolio securities in excess of 10% of its total assets.
    Any loans of portfolio securities will be made according to guidelines
    established by the Trustees, including maintenance of cash collateral of the
    borrower equal at all times to the current market value of the securities
    loaned.
 
    Notwithstanding any other investment policy or restriction, the Fund may
seek to achieve its investment objective by investing all or substantially all
of its assets in another investment company having substantially the same
investment objective and policies as the Fund.
 
III. MANAGEMENT OF THE FUND
- --------------------------------------------------------------------------------
 
A. BOARD OF TRUSTEES
 
    The Board of Trustees of the Fund oversees the management of the Fund but
does not itself manage the Fund. The Trustees review various services provided
by or under the direction of the Investment Manager to ensure that the Fund's
general investment policies and programs are properly carried out. The Trustees
also conduct their review to ensure that administrative services are provided to
the Fund in a satisfactory manner.
 
    Under state law, the duties of the Trustees are generally characterized as a
duty of loyalty and a duty of care. The duty of loyalty requires a Trustee to
exercise his or her powers in the interest of the Fund and not the Trustee's own
interest or the interest of another person or organization. A Trustee satisfies
his or her duty of care by acting in good faith with the care of an ordinarily
prudent person and in a manner the Trustee reasonably believes to be in the best
interest of the Fund and its shareholders.
 
B. MANAGEMENT INFORMATION
 
    TRUSTEES AND OFFICERS.  The Board of the Fund consists of nine (9) Trustees.
These same individuals also serve as directors or trustees for all of the Morgan
Stanley Dean Witter Funds. Seven Trustees (77% of the total number) have no
affiliation or business connection with the Investment Manager or any of its
affiliated persons and do not own any stock or other securities issued by the
Investment Manager's parent company, MSDW. These are the "non-interested" or
"independent" Trustees. The other two Trustees (the "management Trustees") are
affiliated with the Investment Manager. All of the Independent Trustees also
serve as Independent Trustees of "Discover Brokerage Index Series," a mutual
fund for which the Investment Manager is the investment advisor. Four of the
seven Independent Trustees are also Independent Trustees of certain other mutual
funds, referred to as the "TCW/DW Funds," for which MSDW Services Company is the
manager and TCW Funds Management, Inc. is the investment advisor.
 
                                       7
<PAGE>
   
    The Trustees and executive officers of the Fund, their principal business
occupations during the last five years and their affiliations, if any, with the
Investment Manager, and with the 85 Morgan Stanley Dean Witter Funds, the 11
TCW/DW Funds and Discover Brokerage Index Series, are shown below.
    
 
   
<TABLE>
<CAPTION>
      NAME, AGE, POSITION WITH FUND AND ADDRESS                PRINCIPAL OCCUPATIONS DURING LAST FIVE YEARS
- ------------------------------------------------------  ----------------------------------------------------------
<S>                                                     <C>
Michael Bozic (58) ...................................  Vice Chairman of Kmart Corporation (since December, 1998);
Trustee                                                 Director or Trustee of the Morgan Stanley Dean Witter
c/o Kmart Corporation                                   Funds; Trustee of Discover Brokerage Index Series;
3100 West Big Beaver Road                               formerly Chairman and Chief Executive Officer of Levitz
Troy, Michigan                                          Furniture Corporation (November, 1995-November, 1998) and
                                                        President and Chief Executive Officer of Hills Department
                                                        Stores (May, 1991-July, 1995); formerly variously
                                                        Chairman, Chief Executive Officer, President and Chief
                                                        Operating Officer (1987-1991) of the Sears Merchandise
                                                        Group of Sears, Roebuck and Co.; Director of Eaglemark
                                                        Financial Services, Inc. and Weirton Steel Corporation.
 
Charles A. Fiumefreddo* (65) .........................  Chairman, Director or Trustee, President and Chief
Chairman of the Board, President,                       Executive Officer of the Morgan Stanley Dean Witter Funds;
Chief Executive Officer and Trustee                     Chairman, Chief Executive Officer and Trustee of the
Two World Trade Center                                  TCW/DW Funds; Trustee of Discover Brokerage Index Series;
New York, New York                                      formerly Chairman, Chief Executive Officer and Director of
                                                        the Investment Manager, the Distributor and MSDW Services
                                                        Company; Executive Vice President and Director of Dean
                                                        Witter Reynolds; Chairman and Director of the Transfer
                                                        Agent; formerly Director and/or officer of various MSDW
                                                        subsidiaries (until June, 1998).
 
Edwin J. Garn (66) ...................................  Director or Trustee of the Morgan Stanley Dean Witter
Trustee                                                 Funds; Trustee of Discover Brokerage Index Series;
c/o Huntsman Corporation                                formerly United States Senator (R-Utah) (1974-1992) and
500 Huntsman Way                                        Chairman, Senate Banking Committee (1980-1986); formerly
Salt Lake City, Utah                                    Mayor of Salt Lake City, Utah (1971-1974); formerly
                                                        Astronaut, Space Shuttle Discovery (April 12-19, 1985);
                                                        Vice Chairman, Huntsman Corporation; Director of Franklin
                                                        Covey (time management systems), BMW Bank of North
                                                        America, Inc., United Space Alliance (joint venture
                                                        between Lockheed Martin and the Boeing Company) and Nuskin
                                                        Asia Pacific (multilevel marketing); member of the board
                                                        of various civic and charitable organizations.
</TABLE>
    
 
                                       8
<PAGE>
<TABLE>
<CAPTION>
      NAME, AGE, POSITION WITH FUND AND ADDRESS                PRINCIPAL OCCUPATIONS DURING LAST FIVE YEARS
- ------------------------------------------------------  ----------------------------------------------------------
<S>                                                     <C>
John R. Haire (74) ...................................  Chairman of the Audit Committee and Director or Trustee of
Trustee                                                 the Morgan Stanley Dean Witter Funds; Chairman of the
Two World Trade Center                                  Audit Committee and Trustee of the TCW/DW Funds; Chairman
New York, New York                                      of the Audit Committee and Chairman of the Audit Committee
                                                        and Trustee of Discover Brokerage Index Series; formerly
                                                        Chairman of the Independent Directors or Trustees of the
                                                        Morgan Stanley Dean Witter Funds and the TCW/ DW Funds
                                                        (until June, 1998); formerly President, Council for Aid to
                                                        Education (1978-1989) and Chairman and Chief Executive
                                                        Officer of Anchor Corporation, an investment advisor
                                                        (1964-1978).
 
Wayne E. Hedien (65) .................................  Retired; Director or Trustee of the Morgan Stanley Dean
Trustee                                                 Witter Funds; Trustee of Discover Brokerage Index Series;
c/o Gordon Altman Butowsky                              Director of The PMI Group, Inc. (private mortgage
Weitzen Shalov & Wein                                   insurance); Trustee and Vice Chairman of The Field Museum
Counsel to the Independent Trustees                     of Natural History; formerly associated with the Allstate
114 West 47th Street                                    Companies (1966-1994), most recently as Chairman of The
New York, New York                                      Allstate Corporation (March, 1993-December, 1994) and
                                                        Chairman and Chief Executive Officer of its wholly-owned
                                                        subsidiary, Allstate Insurance Company (July,
                                                        1989-December, 1994); director of various other business
                                                        and charitable organizations.
 
Dr. Manuel H. Johnson (50) ...........................  Senior Partner, Johnson Smick International, Inc., a
Trustee                                                 consulting firm; Co-Chairman and a founder of the Group of
c/o Johnson Smick International, Inc.                   Seven Council (G7C), an international economic commission;
1133 Connecticut Avenue, N.W.                           Director or Trustee of the Morgan Stanley Dean Witter
Washington, D.C.                                        Funds; Trustee of the TCW/ DW Funds; Trustee of Discover
                                                        Brokerage Index Series; Director of NASDAQ (since June,
                                                        1995); Director of Greenwich Capital Markets, Inc.
                                                        (broker-dealer) and NVR, Inc. (home construction); Chair-
                                                        man and Trustee of the Financial Accounting Foundation
                                                        (oversight organization of the Financial Accounting
                                                        Standards Board); formerly Vice Chairman of the Board of
                                                        Governors of the Federal Reserve System (1986-1990) and
                                                        Assistant Secretary of the U.S. Treasury.
 
Michael E. Nugent (62) ...............................  General Partner, Triumph Capital, L.P., a private
Trustee                                                 investment partnership; Director or Trustee of the Morgan
c/o Triumph Capital, L.P.                               Stanley Dean Witter Funds; Trustee of the TCW/DW Funds;
237 Park Avenue                                         Trustee of Discover Brokerage Index Series; formerly Vice
New York, New York                                      President, Bankers Trust Company and BT Capital
                                                        Corporation (1984-1988); director of various business
                                                        organizations.
</TABLE>
 
                                       9
<PAGE>
<TABLE>
<CAPTION>
      NAME, AGE, POSITION WITH FUND AND ADDRESS                PRINCIPAL OCCUPATIONS DURING LAST FIVE YEARS
- ------------------------------------------------------  ----------------------------------------------------------
<S>                                                     <C>
Philip J. Purcell* (55) ..............................  Chairman of the Board of Directors and Chief Executive
Trustee                                                 Officer of MSDW, Dean Witter Reynolds and Novus Credit
1585 Broadway                                           Services Inc.; Director of the Distributor; Director or
New York, New York                                      Trustee of the Morgan Stanley Dean Witter Funds; Trustee
                                                        of Discover Brokerage Index Series; Director and/or
                                                        officer of various MSDW subsidiaries.
 
John L. Schroeder (68) ...............................  Retired; Director or Trustee of the Morgan Stanley Dean
Trustee                                                 Witter Funds; Trustee of the TCW/DW Funds; Trustee of
c/o Gordon Altman Butowsky                              Discover Brokerage Index Series; Director of Citizens
Weitzen Shalov & Wein                                   Utilities Company; formerly Executive Vice President and
Counsel to the Independent Trustees                     Chief Investment Officer of the Home Insurance Company
114 West 47th Street                                    (August, 1991-September, 1995).
New York, New York
 
Barry Fink (44) ......................................  Senior Vice President (since March, 1997) and Secretary
Vice President, Secretary and General Counsel           and General Counsel (since February, 1997) and Director
Two World Trade Center                                  (since July, 1998) of the Investment Manager and MSDW
New York, New York                                      Services Company; Senior Vice President (since March,
                                                        1997) and Assistant Secretary and Assistant General
                                                        Counsel (since February, 1997) of the Distributor;
                                                        Assistant Secretary of Dean Witter Reynolds (since August,
                                                        1996); Vice President, Secretary and General Counsel of
                                                        the Morgan Stanley Dean Witter Funds and the TCW/DW Funds
                                                        (since February, 1997); Vice President, Secretary and
                                                        General Counsel of Discover Brokerage Index Series;
                                                        previously First Vice President (June, 1993-February,
                                                        1997), Vice President and Assistant Secretary and
                                                        Assistant General Counsel of the Investment Manager and
                                                        MSDW Services Company and Assistant Secretary of the Mor-
                                                        gan Stanley Dean Witter Funds and the TCW/DW Funds.
 
Jonathan R. Page (52) ................................  Senior Vice President of the Investment Manager; Vice
Senior Vice President                                   President of various Morgan Stanley Dean Witter Funds.
Two World Trade Center
New York, New York
 
Thomas F. Caloia (52) ................................  First Vice President and Assistant Treasurer of the
Treasurer                                               Investment Manager and MSDW Services Company; Treasurer of
Two World Trade Center                                  the Morgan Stanley Dean Witter Funds, the TCW/DW Funds and
New York, New York                                      Discover Brokerage Index Series.
</TABLE>
 
- ------------------------
*Denotes Trustees who are "interested persons" of the Fund as defined by the
Investment Company Act.
 
    In addition, MITCHELL M. MERIN, President and Chief Operating Officer of
Asset Management of MSDW, President, Chief Executive Officer and Director of the
Investment Manager and MSDW Services Company, Chairman and Director of the
Distributor and the Transfer Agent, Executive Vice President and
 
                                       10
<PAGE>
   
Director of Dean Witter Reynolds, and Director of various MSDW subsidiaries,
RONALD E. ROBISON, Executive Vice President, Chief Administrative Officer and
Director of the Investment Manager and MSDW Services Company, ROBERT S.
GIAMBRONE, Senior Vice President of the Investment Manager, MSDW Services
Company, the Distributor and the Transfer Agent and Director of the Transfer
Agent, JOSEPH J. MCALINDEN, Executive Vice President and Chief Investment
Officer of the Investment Manager and Director of the Transfer Agent, and PETER
M. AVELAR, PAUL D. VANCE and JAMES F. WILLISON, Senior Vice Presidents of the
Investment Manager, are Vice Presidents of the Fund.
    
 
   
    In addition, FRANK BRUTTOMASSO, MARILYN K. CRANNEY, LOU ANNE D. MCINNIS,
CARSTEN OTTO and RUTH ROSSI, First Vice Presidents and Assistant General
Counsels of the Investment Manager and MSDW Services Company, and TODD LEBO,
Vice President and Assistant General Counsel of the Investment Manager and MSDW
Services Company, are Assistant Secretaries of the Fund.
    
 
    INDEPENDENT TRUSTEES AND THE COMMITTEES.  Law and regulation establish both
general guidelines and specific duties for the Independent Trustees. The Morgan
Stanley Dean Witter Funds seek as Independent Trustees individuals of
distinction and experience in business and finance, government service or
academia; these are people whose advice and counsel are in demand by others and
for whom there is often competition. To accept a position on the Funds' Boards,
such individuals may reject other attractive assignments because the Funds make
substantial demands on their time. Indeed, by serving on the Funds' Boards,
certain Trustees who would otherwise be qualified and in demand to serve on bank
boards would be prohibited by law from doing so. All of the Independent Trustees
serve as members of the Audit Committee. Three of them also serve as members of
the Derivatives Committee. In addition, three of the Trustees, including two
Independent Trustees, serve as members of the Insurance Committee.
 
    The Independent Trustees are charged with recommending to the full Board
approval of management, advisory and administration contracts, Rule 12b-1 plans
and distribution and underwriting agreements; continually reviewing Fund
performance; checking on the pricing of portfolio securities, brokerage
commissions, transfer agent costs and performance, and trading among Funds in
the same complex; and approving fidelity bond and related insurance coverage and
allocations, as well as other matters that arise from time to time. The
Independent Trustees are required to select and nominate individuals to fill any
Independent Trustee vacancy on the Board of any Fund that has a Rule 12b-1 plan
of distribution. Most of the Morgan Stanley Dean Witter Funds have a Rule 12b-1
plan.
 
    The Audit Committee is charged with recommending to the full Board the
engagement or discharge of the Fund's independent accountants; directing
investigations into matters within the scope of the independent accountants'
duties, including the power to retain outside specialists; reviewing with the
independent accountants the audit plan and results of the auditing engagement;
approving professional services provided by the independent accountants and
other accounting firms prior to the performance of the services; reviewing the
independence of the independent accountants; considering the range of audit and
non-audit fees; reviewing the adequacy of the Fund's system of internal
controls; and preparing and submitting Committee meeting minutes to the full
Board.
 
    The Board of each Fund has a Derivatives Committee to approve parameters for
and monitor the activities of the Fund with respect to derivative investments,
if any, made by the Fund.
 
    Finally, the Board of each Fund has formed an Insurance Committee to review
and monitor the insurance coverage maintained by the Fund.
 
    ADVANTAGES OF HAVING SAME INDIVIDUALS AS INDEPENDENT TRUSTEES FOR ALL MORGAN
STANLEY DEAN WITTER FUNDS.  The Independent Trustees and the Funds' management
believe that having the same Independent Trustees for each of the Morgan Stanley
Dean Witter Funds avoids the duplication of effort that would arise from having
different groups of individuals serving as Independent Trustees for each of the
Funds or even of sub-groups of Funds. They believe that having the same
individuals serve as Independent Trustees of all the Funds tends to increase
their knowledge and expertise regarding matters which affect the Fund complex
generally and enhances their ability to negotiate on behalf of
 
                                       11
<PAGE>
each Fund with the Fund's service providers. This arrangement also precludes the
possibility of separate groups of Independent Trustees arriving at conflicting
decisions regarding operations and management of the Funds and avoids the cost
and confusion that would likely ensue. Finally, having the same Independent
Trustees serve on all Fund Boards enhances the ability of each Fund to obtain,
at modest cost to each separate Fund, the services of Independent Trustees, of
the caliber, experience and business acumen of the individuals who serve as
Independent Trustees of the Morgan Stanley Dean Witter Funds.
 
    TRUSTEE AND OFFICER INDEMNIFICATION.  The Fund's Declaration of Trust
provides that no Trustee, officer, employee or agent of the Fund is liable to
the Fund or to a shareholder, nor is any Trustee, officer, employee or agent
liable to any third persons in connection with the affairs of the Fund, except
as such liability may arise from his/her or its own bad faith, willful
misfeasance, gross negligence or reckless disregard of his/her or its duties. It
also provides that all third persons shall look solely to the Fund property for
satisfaction of claims arising in connection with the affairs of the Fund. With
the exceptions stated, the Declaration of Trust provides that a Trustee,
officer, employee or agent is entitled to be indemnified against all liability
in connection with the affairs of the Fund.
 
C. COMPENSATION
 
   
    The Fund pays each Independent Trustee an annual fee of $800 plus a per
meeting fee of $50 for meetings of the Board of Trustees, the Independent
Trustees or Committees of the Board of Trustees attended by the Trustee (the
Fund pays the Chairman of the Audit Committee an additional annual fee of $750).
If a Board meeting and a meeting of the Independent Trustees or a Committee
meeting, or a meeting of the Independent Trustees and/or more than one Committee
meeting, take place on a single day, the Trustees are paid a single meeting fee
by the Fund. The Fund also reimburses such Trustees for travel and other
out-of-pocket expenses incurred by them in connection with attending such
meetings. Trustees and officers of the Fund who are or have been employed by the
Investment Manager or an affiliated company receive no compensation or expense
reimbursement from the Fund for their services as Trustee. Mr. Haire currently
serves as Chairman of the Audit Committee. Prior to June 1, 1998, Mr. Haire also
served as Chairman of the Independent Trustees for which services the Fund paid
him an additional annual fee of $1,200.
    
 
    The following table illustrates the compensation that the Fund paid to its
Independent Trustees for the fiscal year ended January 31, 1999.
 
                               FUND COMPENSATION
 
   
<TABLE>
<CAPTION>
                                                                   AGGREGATE
                                                                 COMPENSATION
NAME OF INDEPENDENT TRUSTEE                                      FROM THE FUND
- --------------------------------------------------------------  ---------------
<S>                                                             <C>
Michael Bozic.................................................      $1,450
Edwin J. Garn.................................................       1,600
John R. Haire.................................................       2,600
Wayne E. Hedien...............................................       1,600
Dr. Manuel H. Johnson.........................................       1,550
Michael E. Nugent.............................................       1,600
John L. Schroeder.............................................       1,600
</TABLE>
    
 
    The following table illustrates the compensation paid to the Fund's
Independent Trustees for the calendar year ended December 31, 1998 for services
to the 85 Morgan Stanley Dean Witter Funds and, in the case of Messrs. Haire,
Johnson, Nugent and Schroeder, the 11 TCW/DW Funds that were in operation at
December 31, 1998. Mr. Haire serves as Chairman of the Audit Committee of each
Morgan Stanley Dean Witter Fund and each TCW/DW Fund and, prior to June 1, 1998,
also served as Chairman of the Independent Directors or Trustees of those Funds.
With respect to Messrs. Haire, Johnson, Nugent and Schroeder, the TCW/DW Funds
are included solely because of a limited exchange privilege
 
                                       12
<PAGE>
between those Funds and five Morgan Stanley Dean Witter Money Market Funds. No
compensation was paid to the Fund's Independent Trustees by Discover Brokerage
Index Series for the calendar year ended December 31, 1998.
 
    CASH COMPENSATION FROM MORGAN STANLEY DEAN WITTER FUNDS AND TCW/DW FUNDS
 
<TABLE>
<CAPTION>
                                                                   FOR SERVICE AS
                                                                    CHAIRMAN OF                     TOTAL CASH
                                                                    INDEPENDENT     FOR SERVICE    COMPENSATION
                               FOR SERVICE                           DIRECTORS/          AS        FOR SERVICES
                              AS DIRECTOR OR                        TRUSTEES AND    CHAIRMAN OF         TO
                               TRUSTEE AND                             AUDIT        INDEPENDENT      85 MORGAN
                             COMMITTEE MEMBER    FOR SERVICE AS    COMMITTEES OF    TRUSTEES AND      STANLEY
                               OF 85 MORGAN       TRUSTEE AND        85 MORGAN         AUDIT        DEAN WITTER
                                 STANLEY        COMMITTEE MEMBER      STANLEY        COMMITTEES      FUNDS AND
NAME OF                        DEAN WITTER        OF 11 TCW/DW      DEAN WITTER     OF 11 TCW/DW     11 TCW/DW
INDEPENDENT TRUSTEE               FUNDS              FUNDS             FUNDS           FUNDS           FUNDS
- ---------------------------  ----------------   ----------------   --------------   ------------   -------------
<S>                          <C>                <C>                <C>              <C>            <C>
Michael Bozic..............      $120,150           --                 --              --            $120,150
Edwin J. Garn..............       132,450           --                 --              --             132,450
John R. Haire..............       136,450           $66,931           $101,338        $14,725         319,444
Wayne E. Hedien............       132,350           --                 --              --             132,350
Dr. Manuel H. Johnson......       128,400            62,331            --              --             190,731
Michael E. Nugent..........       132,450            62,131            --              --             194,581
John L. Schroeder..........       132,450            64,731            --              --             197,181
</TABLE>
 
    As of the date of this STATEMENT OF ADDITIONAL INFORMATION, 55 of the Morgan
Stanley Dean Witter Funds, including the Fund, have adopted a retirement program
under which an Independent Trustee who retires after serving for at least five
years (or such lesser period as may be determined by the Board) as an
Independent Director or Trustee of any Morgan Stanley Dean Witter Fund that has
adopted the retirement program (each such Fund referred to as an "Adopting Fund"
and each such Trustee referred to as an "Eligible Trustee") is entitled to
retirement payments upon reaching the eligible retirement age (normally, after
attaining age 72). Annual payments are based upon length of service.
 
   
    Currently, upon retirement, each Eligible Trustee is entitled to receive
from the Adopting Fund, commencing as of his or her retirement date and
continuing for the remainder of his or her life, an annual retirement benefit
(the "Regular Benefit") equal to 30.22% of his or her Eligible Compensation plus
0.5036667% of such Eligible Compensation for each full month of service as an
Independent Director or Trustee of any Adopting Fund in excess of five years up
to a maximum of 60.44% after ten years of service. The foregoing percentages may
be changed by the Board.(1) "Eligible Compensation" is one-fifth of the total
compensation earned by such Eligible Trustee for service to the Adopting Fund in
the five year period prior to the date of the Eligible Trustee's retirement.
Benefits under the retirement program are not secured or funded by the Adopting
Funds.
    
 
    The following table illustrates the retirement benefits accrued to the
Fund's Independent Trustees by the Fund for the fiscal year ended January 31,
1999 and by the 55 Morgan Stanley Dean Witter Funds (including the Fund) for the
year ended December 31, 1998, and the estimated retirement benefits for the
Independent Trustees, to commence upon their retirement, from the Fund as of
January 31, 1999 and from the 55 Morgan Stanley Dean Witter Funds as of December
31, 1998.
 
- ------------------------
(1)  An Eligible Trustee may elect alternative payments of his or her retirement
     benefits based upon the combined life expectancy of the Eligible Trustee
     and his or her spouse on the date of such Eligible Trustee's retirement. In
     addition, the Eligible Trustee may elect that the surviving spouse's
     periodic payment of benefits will be equal to a lower percentage of the
     periodic amount when both spouses were alive. The amount estimated to be
     payable under this method, through the remainder of the later of the lives
     of the Eligible Trustee and spouse, will be the actuarial equivalent of the
     Regular Benefit.
 
                                       13
<PAGE>
   RETIREMENT BENEFITS FROM THE FUND AND ALL MORGAN STANLEY DEAN WITTER FUNDS
 
   
<TABLE>
<CAPTION>
                                         FOR ALL ADOPTING FUNDS                                       ESTIMATED ANNUAL
                                  ------------------------------------     RETIREMENT BENEFITS            BENEFITS
                                       ESTIMATED                           ACCRUED AS EXPENSES       UPON RETIREMENT(2)
                                    CREDITED YEARS        ESTIMATED     -------------------------  ----------------------
                                     OF SERVICE AT      PERCENTAGE OF                   BY ALL       FROM      FROM ALL
                                      RETIREMENT          ELIGIBLE        BY THE       ADOPTING       THE      ADOPTING
NAME OF INDEPENDENT TRUSTEE          (MAXIMUM 10)       COMPENSATION       FUND         FUNDS        FUND        FUNDS
- --------------------------------  -------------------  ---------------  -----------  ------------  ---------  -----------
<S>                               <C>                  <C>              <C>          <C>           <C>        <C>
Michael Bozic...................              10             60.44%      $     394   $  22,377     $     937  $    52,250
Edwin J. Garn...................              10             60.44             596      35,225           937       52,250
John R. Haire...................              10             60.44             285     (12,211)(3)     2,440      134,705
Wayne E. Hedien.................               9             51.37             738      41,979           796       44,413
Dr. Manuel H. Johnson...........              10             60.44             239      14,047           937       52,250
Michael E. Nugent...............              10             60.44             419      25,336           937       52,250
John L. Schroeder...............               8             50.37             804      45,117           796       44,343
</TABLE>
    
 
- ------------------------
(2)  Based on current levels of compensation. Amount of annual benefits also
     varies depending on the Trustee's elections described in Footnote (1)
     above.
(3)  This number reflects the effect of the extension of Mr. Haire's term as
     Director or Trustee until May 1, 1999.
 
IV. CONTROL PERSONS AND PRINCIPAL HOLDERS OF SECURITIES

- --------------------------------------------------------------------------------
 
   
    The following owned 5% or more of the outstanding shares of the Fund on
February 26, 1999: Mellon Bank N.A., Mutual Funds, P.O. Box 3198, Pittsburgh PA
15230, as trustee of the Morgan Stanley Dean Witter START Plan, an employee
benefit plan established under Sections 401(a) and 401(k) of the Internal
Revenue Code for the benefit of certain employees of MSDW and its subsidiaries
- -- 9.36%.
    
 
    As of the date of this STATEMENT OF ADDITIONAL INFORMATION, the aggregate
number of shares of beneficial interest of the Fund owned by the Fund's officers
and Trustees as a group was less than 1% of the Fund's shares of beneficial
interest outstanding.
 
V. INVESTMENT MANAGEMENT AND OTHER SERVICES
- --------------------------------------------------------------------------------
 
A. INVESTMENT MANAGER
 
    The Investment Manager to the Fund is Morgan Stanley Dean Witter Advisors
Inc., a Delaware corporation, whose address is Two World Trade Center, New York,
New York 10048. The Investment Manager is a wholly-owned subsidiary of MSDW, a
Delaware corporation. MSDW is a preeminent global financial services firm that
maintains leading market positions in each of its three primary businesses:
securities, asset management and credit services.
 
    Pursuant to an Investment Management Agreement (the "Management Agreement")
with the Investment Manager, the Fund has retained the Investment Manager to
provide administrative services and manage the investment of the Fund's assets,
including the placing of orders for the purchase and sale of portfolio
securities. The Fund pays the Investment Manager monthly compensation calculated
daily by applying the following annual rates to the net assets of the Fund,
determined as of the close of business on every business day: 0.50% of the
portion of the daily net assets not exceeding $500 million; 0.425% of the
portion of the daily net assets exceeding $500 million but not exceeding $750
million; 0.375% of the portion of the daily net assets exceeding $750 million
but not exceeding $1 billion; 0.35% of the portion of the daily net assets
exceeding $1 billion but not exceeding $1.5 billion; 0.325% of the portion of
the daily net assets exceeding $1.5 billion but not exceeding $2 billion; 0.30%
of the portion of the daily net assets exceeding $2 billion but not exceeding
$2.5 billion; 0.275% of the portion of the daily net assets exceeding $2.5
billion but not exceeding $3 billion; and 0.25% of the portion of the daily net
assets exceeding $3 billion.
 
                                       14
<PAGE>
   
    For the fiscal years ended January 31, 1997, 1998 and 1999, the Investment
Manager accrued total compensation under the Management Agreement in the amounts
of $4,190,754, $4,108,339 and $4,236,205, respectively.
    
 
    The Investment Manager has retained its wholly-owned subsidiary, MSDW
Services Company, to perform administrative services for the Fund.
 
B. PRINCIPAL UNDERWRITER
 
   
    The Fund's principal underwriter is the Distributor (which has the same
address as the Investment Manager). In this capacity, the Fund's shares are
distributed by the Distributor. The Distributor has entered into a selected
dealer agreement with Dean Witter Reynolds, which through its own sales
organization sells shares of the Fund. In addition, the Distributor may enter
into similar agreements with other selected broker-dealers. The Distributor, a
Delaware corporation, is a wholly-owned subsidiary of MSDW.
    
 
    The Fund and the Distributor have agreed to indemnify each other against
certain liabilities, including liabilities under the Securities Act. Under the
Distribution Agreement, the Distributor uses its best efforts in rendering
services to the Fund, but in the absence of willful misfeasance, bad faith,
gross negligence or reckless disregard of its obligations, the Distributor is
not liable to the Fund or any of its shareholders for any error of judgment or
mistake of law or for any act or omission or for any losses sustained by the
Fund or its shareholders.
 
C. SERVICES PROVIDED BY THE INVESTMENT MANAGER AND FUND EXPENSES PAID BY THIRD
PARTIES
 
    The Investment Manager manages the investment of the Fund's assets,
including the placing of orders for the purchase and sale of portfolio
securities. The Investment Manager obtains and evaluates the information and
advice relating to the economy, securities markets, and specific securities as
it considers necessary or useful to continuously manage the assets of the Fund
in a manner consistent with its investment objective.
 
    Under the terms of the Management Agreement, in addition to managing the
Fund's investments, the Investment Manager maintains certain of the Fund's books
and records and furnishes, at its own expense, the office space, facilities,
equipment, clerical help, bookkeeping and certain legal services as the Fund may
reasonably require in the conduct of its business, including the preparation of
prospectuses, proxy statements and reports required to be filed with federal and
state securities commissions (except insofar as the participation or assistance
of independent accountants and attorneys is, in the opinion of the Investment
Manager, necessary or desirable). In addition, the Investment Manager pays the
salaries of all personnel, including officers of the Fund, who are employees of
the Investment Manager. The Investment Manager also bears the cost of telephone
service, heat, light, power and other utilities provided to the Fund.
 
    Expenses not expressly assumed by the Investment Manager under the
Management Agreement or by the Distributor, will be paid by the Fund. These
expenses include, but are not limited to: expenses of the Plan of Distribution
pursuant to Rule 12b-1; charges and expenses of any registrar, custodian, stock
transfer and dividend disbursing agent; brokerage commissions; taxes; engraving
and printing share certificates; registration costs of the Fund and its shares
under federal and state securities laws; the cost and expense of printing,
including typesetting, and distributing prospectuses of the Fund and supplements
thereto to the Fund's shareholders; all expenses of shareholders' and Trustees'
meetings and of preparing, printing and mailing of proxy statements and reports
to shareholders; fees and travel expenses of Trustees or members of any advisory
board or committee who are not employees of the Investment Manager or any
corporate affiliate of the Investment Manager; all expenses incident to any
dividend, withdrawal or redemption options; charges and expenses of any outside
service used for pricing of the Fund's shares; fees and expenses of legal
counsel, including counsel to the Trustees who are not interested persons of the
Fund or of the Investment Manager (not including compensation or expenses of
attorneys who are employees of the Investment Manager); fees and expenses of the
Fund's independent accountants; membership dues of industry associations;
interest on Fund borrowings;
 
                                       15
<PAGE>
postage; insurance premiums on property or personnel (including officers and
Trustees) of the Fund which inure to its benefit; extraordinary expenses
(including, but not limited to, legal claims and liabilities and litigation
costs and any indemnification relating thereto); and all other costs of the
Fund's operation.
 
    The Management Agreement provides that in the absence of willful
misfeasance, bad faith, gross negligence or reckless disregard of its
obligations thereunder, the Investment Manager is not liable to the Fund or any
of its investors for any act or omission by the Investment Manager or for any
losses sustained by the Fund or its investors.
 
   
    The Management Agreement will remain in effect from year to year, provided
continuance of the Management Agreement is approved at least annually by the
vote of the holders of a majority, as defined in the Investment Company Act, of
the outstanding shares of the Fund, or by the Trustees; provided that in either
event such continuance is approved annually by the vote of a majority of the
Trustees.
    
 
D. RULE 12B-1 PLAN
 
    In accordance with a Plan of Distribution pursuant to Rule 12b-1 under the
Investment Company Act between the Fund and the Distributor, the Distributor
provides certain services in connection with the promotion of sales of Fund
shares (the "Plan").
 
    The Plan provides that the Distributor bears the expense of all promotional
and distribution related activities on behalf of the Fund, except for expenses
that the Trustees determine to reimburse, as described below. The following
activities and services may be provided by the Distributor under the Plan: (1)
compensation to and expenses of Dean Witter Reynolds' and other selected
Broker-Dealers' Financial Advisors and other employees, including overhead and
telephone expenses; (2) sales incentives and bonuses to sales representatives
and to marketing personnel in connection with promoting sales of the Fund's
shares; (3) expenses incurred in connection with promoting sales of the Fund's
shares; (4) preparing and distributing sales literature; and (5) providing
advertising and promotional activities, including direct mail solicitation and
television, radio, newspaper, magazine and other media advertisements.
 
    Dean Witter Reynolds Financial Advisors are paid an annual residual
commission, currently a residual of up to 0.10% of the current value of the
respective accounts for which they are the Financial Advisors of record. The
residual is a charge which reflects residual commissions paid by Dean Witter
Reynolds to its Financial Advisors and Dean Witter Reynolds' expenses associated
with the servicing of shareholders' accounts, including the expenses of
operating Dean Witter Reynolds' branch offices in connection with the servicing
of shareholders' accounts, which expenses include lease costs, the salaries and
employee benefits of operations and sales support personnel, utility costs,
communications costs and the costs of stationery and supplies and other expenses
relating to branch office serving of shareholder accounts.
 
    The Fund is authorized to reimburse specific expenses incurred or to be
incurred in promoting the distribution of the Fund's shares. Reimbursement is
made through payments at the end of each month. The amount of each monthly
payment may in no event exceed an amount equal to a payment at the annual rate
of 0.15 of 1% of the Fund's average daily net assets during the month. No
interest or other financing charges will be incurred for which reimbursement
payments under the Plan will be made. In addition, no interest charges, if any,
incurred on any distribution expense incurred by the Distributor or other
selected dealers pursuant to the Plan, will be reimbursable under the Plan. In
the case of all expenses other than expenses representing a residual to
Financial Advisors, such amounts shall be determined at the beginning of each
calendar quarter by the Trustees, including a majority of the Independent 12b-1
Trustees. Expenses representing a residual to Financial Advisors may be
reimbursed without prior determination. In the event that the Distributor
proposes that monies shall be reimbursed for other than such expenses, then in
making quarterly determinations of the amounts that may be expended by the Fund,
the Investment Manager provides and the Trustees review a quarterly budget of
projected incremental distribution expenses to be incurred on behalf of the
Fund, together with a report explaining the purposes and anticipated benefits of
incurring such expenses. The Trustees determine
 
                                       16
<PAGE>
which particular expenses, and the portions thereof, that may be borne by the
Fund, and in making such a determination shall consider the scope of the
Distributor's commitment to promoting the distribution of the Fund's shares.
 
   
    The Fund reimbursed $903,926 to the Distributor pursuant to the Plan which
amounted to 0.10 of 1% of the Fund's average daily net assets for the fiscal
year ended January 31, 1999. Based upon the total amounts spent by the
Distributor during the period, it is estimated that the amount paid by the Fund
to the Distributor for distribution was spent in approximately the following
ways: (i) advertising -- $-0-; (ii) printing and mailing PROSPECTUSES to other
than current shareholders -- $-0-; (iii) compensation to underwriters -- $-0-;
(iv) compensation to dealers --$-0-; (v) compensation to sales personnel --
$-0-; and (vi) other, which includes payments to Dean Witter Reynolds for
expenses substantially all of which relate to compensation of sales personnel
and associated overhead expenses -- $903,926. No payments under the Plan were
made for interest, carrying or other financing charges.
    
 
    Under the Plan, the Distributor uses its best efforts in rendering services
to the Fund, but in the absence of willful misfeasance, bad faith, gross
negligence or reckless disregard of its obligations, the Distributor is not
liable to the Fund or any of its shareholders for any error of judgment or
mistake of law or for any act or omission or for any losses sustained by the
Fund or its shareholders.
 
    Under the Plan, the Distributor provides the Fund, for review by the
Trustees, and the Trustees review, promptly after the end of each calendar
quarter, a written report regarding the incremental distribution expenses
incurred on behalf of the Fund during such calendar quarter, which report
includes (1) an itemization of the types of expenses and the purposes therefore;
(2) the amounts of such expenses; and (3) a description of the benefits derived
by the Fund. In the Trustees' quarterly review of the Plan they consider its
continued appropriateness and the level of compensation provided therein.
 
    No interested person of the Fund nor any Independent Trustee has any direct
financial interest in the operation of the Plan except to the extent that the
Distributor, the Investment Manager, Dean Witter Reynolds, MSDW Services Company
or certain of their employees may be deemed to have such an interest as a result
of benefits derived from the successful operation of the Plan or as a result of
receiving a portion of the amounts expended thereunder by the Fund.
 
   
    On an annual basis, the Trustees, including a majority of the Independent
Trustees, consider whether the Plan should be continued. Prior to approving the
most recent continuation of the Plan, the Trustees requested and received from
the Distributor and reviewed all the information which they deemed necessary to
arrive at an informed determination. In making their determination to continue
the Plan, the Trustees considered: (1) the Fund's experience under the Plan and
whether such experience indicates that the Plan is operating as anticipated; (2)
the benefits the Fund had obtained, was obtaining and would be likely to obtain
under the Plan, including that: (a) the Plan is essential in order to implement
the Fund's method and to enable the Fund to continue to grow and avoid a pattern
of net redemptions which, in turn, are essential for effective investment
management; and (b) without the reimbursement of distribution and account
maintenance expenses of Dean Witter Reynolds' branch offices made possible by
the 12b-1 fees, Dean Witter Reynolds could not establish and maintain an
effective system for distribution, servicing of Fund shareholders and
maintenance of shareholder accounts; and (3) what services had been provided and
were continuing to be provided under the Plan to the Fund and its shareholders.
Based upon their review, the Trustees, including each of the Independent
Trustees, determined that continuation of the Plan would be in the best interest
of the Fund and would have a reasonable likelihood of continuing to benefit the
Fund and its shareholders. In the Trustees' quarterly review of the Plan, they
will consider its continued appropriateness and the level of compensation
provided therein.
    
 
    The Plan may not be amended to increase materially the amount to be spent
for the services described therein without approval by the shareholders of the
Fund, and all material amendments to the Plan must also be approved by the
Trustees in the manner described above. The Plan may be terminated at any time,
without payment of any penalty, by vote of a majority of the Independent
Trustees or by a vote of a majority of the outstanding voting securities of the
Fund (as defined in the Investment
 
                                       17
<PAGE>
Company Act) on not more than thirty days' written notice to any other party to
the Plan. So long as the Plan is in effect, the election and nomination of
Independent Trustees shall be committed to the discretion of the Independent
Trustees.
 
E. OTHER SERVICE PROVIDERS
 
   
(1) TRANSFER AGENT/DIVIDEND-PAYING AGENT
    
 
   
    Morgan Stanley Dean Witter Trust FSB is the transfer agent for the Fund's
shares and the Dividend Disbursing Agent for payment of dividends and
distributions on Fund shares and Agent for shareholders under various investment
plans. The principal business address of the Transfer Agent is Harborside
Financial Center, Plaza Two, Jersey City, New Jersey 07311.
    
 
(2) CUSTODIAN AND INDEPENDENT ACCOUNTANTS
 
    The Bank of New York, 90 Washington Street, New York, New York 10286 is the
Custodian for the Fund's assets. Any of the Fund's cash balances with the
Custodian in excess of $100,000 are unprotected by federal deposit insurance.
These balances may, at times, be substantial.
 
   
    PricewaterhouseCoopers LLP, 1177 Avenue of the Americas, New York, New York
10036 serves as the independent accountants of the Fund. The independent
accountants are responsible for auditing the annual financial statements of the
Fund.
    
 
(3) AFFILIATED PERSONS
 
    The Transfer Agent is an affiliate of the Investment Manager, and of the
Distributor. As Transfer Agent and Dividend Disbursing Agent, the Transfer
Agent's responsibilities include maintaining shareholder accounts, disbursing
cash dividends and reinvesting dividends, processing account registration
changes, handling purchase and redemption transactions, mailing prospectuses and
reports, mailing and tabulating proxies, processing share certificate
transactions, and maintaining shareholder records and lists. For these services,
the Transfer Agent receives a per shareholder account fee from the Fund.
 
VI. BROKERAGE ALLOCATION AND OTHER PRACTICES
- --------------------------------------------------------------------------------
 
A. BROKERAGE TRANSACTIONS
 
    Subject to the general supervision of the Trustees, the Investment Manager
is responsible for decisions to buy and sell securities for the Fund, the
selection of brokers and dealers to effect the transactions, and the negotiation
of brokerage commissions, if any. Purchases and sales of portfolio securities
are normally transacted through issuers, underwriters or major dealers in U.S.
Government securities acting as principals. Such transactions are made on a net
basis and do not involve payment of brokerage commissions. The cost of
securities purchased from an underwriter usually includes a commission paid by
the issuer to the underwriters; transactions with dealers normally reflect the
spread between bid and asked prices.
 
    During the fiscal years ended January 31, 1997, 1998 and 1999, the Fund paid
no such brokerage commissions or concessions.
 
B. COMMISSIONS
 
    Pursuant to an order of the SEC, the Fund may effect principal transactions
in certain money market instruments with Dean Witter Reynolds. The Fund will
limit its transactions with Dean Witter Reynolds to U.S. Government and
Government Agency Securities. The transactions will be effected with Dean Witter
Reynolds only when the price available from Dean Witter Reynolds is better than
that available from other dealers.
 
                                       18
<PAGE>
    During the fiscal years ended January 31, 1997, 1998 and 1999, the Fund did
not effect any principal transactions with Dean Witter Reynolds.
 
    Consistent with the policy described above, brokerage transactions in
securities listed on exchanges or admitted to unlisted trading privileges may be
effected through Dean Witter Reynolds, Morgan Stanley & Co. and other affiliated
brokers and dealers. In order for an affiliated broker or dealer to effect any
portfolio transactions on an exchange for the Fund, the commissions, fees or
other remuneration received by the affiliated broker or dealer must be
reasonable and fair compared to the commissions, fees or other remuneration paid
to other brokers in connection with comparable transactions involving similar
securities being purchased or sold on an exchange during a comparable period of
time. This standard would allow the affiliated broker or dealer to receive no
more than the remuneration which would be expected to be received by an
unaffiliated broker in a commensurate arm's-length transaction. Furthermore, the
Trustees, including the Independent Trustees, have adopted procedures which are
reasonably designed to provide that any commissions, fees or other remuneration
paid to an affiliated broker or dealer are consistent with the foregoing
standard. The Fund does not reduce the management fee it pays to the Investment
Manager by any amount of the brokerage commissions it may pay to an affiliated
broker or dealer.
 
    During the fiscal years ended January 31, 1997, 1998 and 1999, the Fund paid
no brokerage commissions to an affiliated broker or dealer.
 
C. BROKERAGE SELECTION
 
    The policy of the Fund regarding purchases and sales of securities for its
portfolio is that primary consideration will be given to obtaining the most
favorable prices and efficient executions of transactions.
 
    In seeking to implement the Fund's policies, the Investment Manager effects
transactions with those brokers and dealers who the Investment Manager believes
provide the most favorable prices and are capable of providing efficient
executions. If the Investment Manager believes the prices and executions are
obtainable from more than one broker or dealer, it may give consideration to
placing portfolio transactions with those brokers and dealers who also furnish
research and other services to the Fund or the Investment Manager. The services
may include, but are not limited to, any one or more of the following:
information as to the availability of securities for purchase or sale;
statistical or factual information or opinions pertaining to investment; wire
services; and appraisals or evaluations of portfolio securities.
 
    The information and services received by the Investment Manager from brokers
and dealers may be of benefit to the Investment Manager in the management of
accounts of some of its other clients and may not in all cases benefit the Fund
directly. While the receipt of such information and services is useful in
varying degrees and would generally reduce the amount of research or services
otherwise performed by the Investment Manager and thereby reduce its expenses,
it is of indeterminable value and the Fund does not reduce the management fee it
pays to the Investment Manager by any amount that may be attributable to the
value of such services.
 
    Subject to the principle of obtaining best price and execution, the
Investment Manager may consider a broker-dealer's sales of shares of the Fund as
a factor in selecting from among those broker-dealers qualified to provide
comparable prices and execution on the Fund's portfolio transactions. The Fund
does not, however, require a broker-dealer to sell shares of the Fund in order
for it to be considered to execute portfolio transactions, and will not enter
into any arrangement whereby a specific amount or percentage of the Fund's
transactions will be directed to a broker which sells shares of the Fund to
customers. The Trustees review, periodically, the allocation of brokerage orders
to monitor the operation of these policies.
 
    The Investment Manager currently serves as investment manager to a number of
clients, including other investment companies, and may in the future act as
investment manager or advisor to others. It is the practice of the Investment
Manager to cause purchase and sale transactions to be allocated among
 
                                       19
<PAGE>
the Fund and others whose assets it manages in such manner as it deems
equitable. In making such allocations among the Fund and other client accounts,
various factors may be considered, including the respective investment
objectives, the relative size of portfolio holdings of the same or comparable
securities, the availability of cash for investment, the size of investment
commitments generally held and the opinions of the persons responsible for
managing the portfolios of the Fund and other client accounts. In the case of
certain initial and secondary public offerings, the Investment Manager utilizes
a pro rata allocation process based on the size of the Morgan Stanley Dean
Witter Funds involved and the number of shares available from the public
offering.
 
D. DIRECTED BROKERAGE
 
    During the fiscal year ended January 31, 1999, the Fund did not pay any
brokerage commissions to brokers because of research services provided.
 
E. REGULAR BROKER-DEALERS
 
    During the fiscal year ended January 31, 1999, the Fund did not purchase
securities issued by brokers or dealers that were among the ten brokers or the
ten dealers which executed transactions for or with the Fund in the largest
dollar amounts during the year. At January 31, 1999, the Fund did not own any
securities issued by any of such issuers.
 
VII. CAPITAL STOCK AND OTHER SECURITIES
- --------------------------------------------------------------------------------
 
    The shareholders of the Fund are entitled to a full vote for each full share
of beneficial interest held. The Fund is authorized to issue an unlimited number
of shares of beneficial interest. All shares of beneficial interest of the Fund
are of $0.01 par value and are equal as to earnings, assets and voting
privileges.
 
    The Fund's Declaration of Trust permits the Trustees to authorize the
creation of additional series of shares (the proceeds of which would be invested
in separate, independently managed portfolios) and additional Classes of shares
within any series. The Trustees have not presently authorized any such
additional series or Classes of shares other than as set forth in the
PROSPECTUS.
 
    The Fund is not required to hold annual meetings of shareholders and in
ordinary circumstances the Fund does not intend to hold such meetings. The
Trustees may call special meetings of shareholders for action by shareholder
vote as may be required by the Investment Company Act or the Declaration of
Trust. Under certain circumstances, the Trustees may be removed by action of the
Trustees or by the shareholders.
 
    Under Massachusetts law, shareholders of a business trust may, under certain
limited circumstances, be held personally liable as partners for the obligations
of the Fund. However, the Declaration of Trust contains an express disclaimer of
shareholder liability for acts or obligations of the Fund, requires that notice
of such Fund obligations include such disclaimer, and provides for
indemnification out of the Fund's property for any shareholder held personally
liable for the obligations of the Fund. Thus, the risk of a shareholder
incurring financial loss on account of shareholder liability is limited to
circumstances in which the Fund itself would be unable to meet its obligations.
Given the above limitations on shareholder personal liability, and the nature of
the Fund's assets and operations, the possibility of the Fund being unable to
meet its obligations is remote and thus, in the opinion of Massachusetts counsel
to the Fund, the risk to Fund shareholders of personal liability is remote.
 
    All of the Trustees have been elected by the shareholders of the Fund, most
recently at a Special Meeting of Shareholders held on May 21, 1997. The Trustees
themselves have the power to alter the number and the terms of office of the
Trustees (as provided for in the Declaration of Trust), and they may at any time
lengthen or shorten their own terms or make their terms of unlimited duration
and appoint their own successors, provided that always at least a majority of
the Trustees has been elected by the shareholders of the Fund.
 
                                       20
<PAGE>
VIII. PURCHASE, REDEMPTION AND PRICING OF SHARES
- --------------------------------------------------------------------------------
 
A. PURCHASE/REDEMPTION OF SHARES
 
    Information concerning how Fund shares are offered to the public (and how
they are redeemed and exchanged) is provided in the Fund's PROSPECTUS.
 
    TRANSFER AGENT AS AGENT.  With respect to the redemption or repurchase of
Fund shares, the application of proceeds to the purchase of new shares in the
Fund or any other Morgan Stanley Dean Witter Funds and the general
administration of the exchange privilege, the Transfer Agent acts as agent for
the Distributor and for the shareholder's authorized broker-dealer, if any, in
the performance of such functions. With respect to exchanges, redemptions or
repurchases, the Transfer Agent shall be liable for its own negligence and not
for the default or negligence of its correspondents or for losses in transit.
The Fund shall not be liable for any default or negligence of the Transfer
Agent, the Distributor or any authorized broker-dealer.
 
    The Distributor and any authorized broker-dealer have appointed the Transfer
Agent to act as their agent in connection with the application of proceeds of
any redemption of Fund shares to the purchase of shares of any other Morgan
Stanley Dean Witter Fund and the general administration of the exchange
privilege. No commission or discounts will be paid to the Distributor or any
authorized broker-dealer for any transaction pursuant to the exchange privilege.
 
    REDEMPTIONS.  A check drawn by a shareholder against his or her account in
the Fund constitutes a request for redemption of a number of shares sufficient
to provide proceeds equal to the amount of the check. Payment of the proceeds
will normally be made on the next business day after receipt by the Transfer
Agent of the check in proper form. If a check is presented for payment to the
Transfer Agent by a shareholder or payee in person, the Transfer Agent will make
payment by means of a check drawn on the Fund's account or, in the case of a
shareholder payee, to the shareholder's predesignated bank account, but will not
make payment in cash.
 
B. OFFERING PRICE
 
    The price of Fund shares, called "net asset value," is based on the value of
the Fund's portfolio securities.
 
    The Fund utilizes the amortized cost method in valuing its portfolio
securities for purposes of determining the net asset value of its shares. The
Fund utilizes the amortized cost method in valuing its portfolio securities even
though the portfolio securities may increase or decrease in market value,
generally in connection with changes in interest rates. The amortized cost
method of valuation involves valuing a security at its cost at the time of
purchase adjusted by a constant amortization to maturity of any discount or
premium, regardless of the impact of fluctuating interest rates on the market
value of the instrument. While this method provides certainty in valuation, it
may result in periods during which value, as determined by amortized cost, is
higher or lower than the price the Fund would receive if it sold the investment.
During such periods, the yield to investors in the Fund may differ somewhat from
that obtained in a similar company which uses market-to-market values for all of
its portfolio securities. For example, if the use of amortized cost resulted in
a lower (higher) aggregate portfolio value on a particular day, a prospective
investor in the Fund would be able to obtain a somewhat higher (lower) yield
than would result from investment in such a similar company and existing
investors would receive less (more) investment income. The purpose of this
method of calculation is to facilitate the maintenance of a constant net asset
value per share of $1.00.
 
    The use of the amortized cost method to value the portfolio securities of
the Fund and the maintenance of the per share net asset value of $1.00 is
permitted pursuant to Rule 2a-7 of the Act (the "Rule") and is conditioned on
its compliance with various conditions contained in the Rule including: (a) the
Trustees are obligated, as a particular responsibility within the overall duty
of care owed to the Fund's shareholders, to establish procedures reasonably
designed, taking into account current market conditions and the Fund's
investment objectives, to stabilize the net asset value per share as computed
for the purpose of distribution and redemption at $1.00 per share; (b) the
procedures include (i) calculation, at
 
                                       21
<PAGE>
such intervals as the Trustees determine are appropriate and as are reasonable
in light of current market conditions, of the deviation, if any, between net
asset value per share using amortized cost to value portfolio securities and net
asset value per share based upon available market quotations with respect to
such portfolio securities; (ii) periodic review by the Trustees of the amount of
deviation as well as methods used to calculate it; and (iii) maintenance of
written records of the procedures, and the Trustees' considerations made
pursuant to them and any actions taken upon such consideration; (c) the Trustees
should consider what steps should be taken, if any, in the event of a difference
of more than 1/2 of 1% between the two methods of valuation; and (d) the
Trustees should take such action as they deem appropriate (such as shortening
the average portfolio maturity, realizing gains or losses, withholding dividends
or, as provided by the Declaration of Trust, reducing the number of outstanding
shares of the Fund) to eliminate or reduce to the extent reasonably practicable
material dilution or other unfair results to investors or existing shareholders
which might arise from differences between the two method of valuation.
 
    Generally, for purposes of the procedures adopted under the Rule, the
maturity of a portfolio security is deemed to be the period remaining
(calculated from the trade date or such other date on which the Fund's interest
in the instrument is subject to market action) until the date on which in
accordance with the terms of the security the principal amount must
unconditionally be paid, or in the case of a security called for redemption, the
date on which the redemption payment must be made.
 
    A variable rate security that is subject to a demand feature is deemed to
have a maturity equal to the period remaining until the principal amount can be
recovered through demand. A floating rate security that is subject to a demand
feature is deemed to have a maturity equal to the period remaining until the
principal amount can be recovered through demand.
 
    An "NRSRO" is a nationally recognized statistical rating organization. The
term "Requisite NRSROs" means (i) any two NRSROs that have issued a rating with
respect to a security or class of debt obligations of an issuer, or (ii) if only
one NRSRO has issued a rating with respect to such security or issuer at the
time a fund purchases or rolls over the security, that NRSRO.
 
    An Eligible Security is generally defined in the Rule to mean (i) a rated
security with a remaining maturity of 397 calendar days or less that has
received a rating from the Requisite NRSROs in one of the two highest short-term
rating categories (within which there may be sub-categories or gradations
indicating relative standing); or (ii) An Unrated Security that is of comparable
quality to a security meeting the requirements of (1) above, as determined by
Trustees; (iii) In addition, in the case of a security that is subject to a
Demand Feature or Guarantee: (A) The Guarantee has received a rating from an
NRSRO or the Guarantee is issued by a guarantor that has received a rating from
an NRSRO with respect to a class of debt obligations (or any debt obligation
within that class) that is comparable in priority and security to the Guarantee,
unless: (1) the Guarantee is issued by a person that directly or indirectly,
controls, is controlled by or is under a common control with the issuer of the
security subject to the Guarantee (other than a sponsor or a Special Purpose
Entity with respect to an Asset Backed Security: (2) the security subject to the
Guarantee is a repurchase agreement that is Collateralized Fully; or (3) the
Guarantee itself is a Government Security and (B) the issuer of the Demand
Feature, or another institution, has undertaken promptly to notify the holder of
the security in the event the Demand Feature or Guarantee is substituted with
another Demand Feature or Guarantee (if such substitution is permissible under
the terms of the Demand Feature or Guarantee). The Fund will limit its
investments to securities that meet the requirements for Eligible Securities.
 
    As permitted by the Rule, the Trustees have delegated to the Fund's
Investment Manager the authority to determine which securities present minimal
credit risks and which unrated securities are comparable in quality to rated
securities.
 
    Also, as required by the Rule, the Fund will limit its investments in
securities, other than Government securities, so that, at the time of purchase:
(a) except as further limited in (b) below with regard to certain securities, no
more than 5% of its total assets will be invested in the securities of any one
issuer; and (b) with respect to Eligible Securities that have received a rating
in less than the highest category by any one
 
                                       22
<PAGE>
of the NRSROs whose ratings are used to qualify the security as an Eligible
Security, or that have been determined to be of comparable quality: (i) no more
than 5% in the aggregate of the Fund's total assets in all such securities, and
(ii) no more than the greater of 1% of total assets, or $1 million, in the
securities on any one issuer.
 
    The Rule further requires that the Fund limit its investments to U.S.
dollar-denominated instruments which the Trustees determine present minimal
credit risks and which are Eligible Securities. The Rule also requires the Fund
to maintain a dollar-weighted average portfolio maturity (not more than 90 days)
appropriate to its objective of maintaining a stable net asset value of $1.00
per share and precludes the purchase of any instrument with a remaining maturity
of more than 397 days. Should the disposition of a portfolio security result in
a dollar-weighted average portfolio maturity of more than 90 days, the Fund will
invest its available cash in such a manner as to reduce such maturity to 90 days
or less a soon as is reasonably practicable.
 
    If the Trustees determine that it is no longer in the best interests of the
Fund and its shareholders to maintain a stable price of $1 per share or if the
Trustees believe that maintaining such price no longer reflects a market-based
net asset value per share, the Trustees have the right to change from an
amortized cost basis of valuation to valuation based on market quotations. The
Fund will notify shareholders of the Fund of any such change.
 
IX. TAXATION OF THE FUND AND SHAREHOLDERS
- --------------------------------------------------------------------------------
 
    The Fund intends to distribute all of its daily net investment income (and
net short-term capital gains, if any) to shareholders of record as of the close
of business the preceding business day. Net income, for dividend purposes,
includes accrued interest and amortization of acquisition, original issue and
market discount, plus or minus any short-term gains or losses realized on sales
of portfolio securities, less the amortization of market premium and the
estimated expenses of the Fund. Net income will be calculated immediately prior
to the determination of net asset value per share of the Fund.
 
    The Trustees of the Fund may revise the dividend policy, or postpone the
payment of dividends, if the Fund should have or anticipate any large unexpected
expense, loss or fluctuation in net assets which, in the opinion of the
Trustees, might have a significant adverse effect on shareholders. On occasion,
in order to maintain a constant $1.00 per share net asset value, the Trustees
may direct that the number of outstanding shares be reduced in each
shareholder's account. Such reduction may result in taxable income to a
shareholder in excess of the net increase (i.e., dividends, less such
reductions), if any, in the shareholder's account for a period of time.
Furthermore, such reduction may be realized as a capital loss when the shares
are liquidated.
 
    It has been and remains the Trust's policy and practice that, if checks for
dividends or distributions paid in cash remain uncashed, no interest will accrue
on amounts represented by such uncashed checks.
 
    TAXES.  The Fund has qualified and intends to remain qualified as a
regulated investment company under Subchapter M of the Internal Revenue Code. If
so qualified, the Fund will not be subject to federal income taxes, provided
that it distributes all of its taxable net investment income and all of its net
realized gains.
 
    Shareholders will be subject to federal income tax on dividends paid from
interest income derived from taxable securities and on distributions of realized
net short-term capital gains and long-term capital gains. Interest and realized
net short-term capital gains distributions are taxable to the shareholder as
ordinary dividend income regardless of whether the shareholder receives such
distributions in additional shares or in cash. Since the Trust's income is
expected to be derived entirely from interest rather than dividends, none of
such distributions will be eligible for the federal dividends received deduction
available to corporations. Realized net long-term capital gains distributions,
which are taxable as long-term capital gains, are not eligible for the dividends
received deduction.
 
                                       23
<PAGE>
    Under present Massachusetts law, the Fund is not subject to any
Massachusetts income tax during any fiscal year in which the Fund qualifies as a
regulated investment company. The Fund might be subject to Massachusetts income
taxes for any taxable year in which it does not so qualify as a regulated
investment company.
 
    The Fund may be subject to tax or taxes in certain states where it does
business. Furthermore, in those states which have income tax laws, the tax
treatment of the Fund and of shareholders with respect to distributions by the
Fund may differ from federal tax treatment.
 
    Shareholders are urged to consult their own tax advisors regarding specific
questions as to federal, state or local taxes.
 
X. UNDERWRITERS
- --------------------------------------------------------------------------------
 
    The Fund's shares are offered to the public on a continuous basis. The
Distributor, as the principal underwriter of the shares, has certain obligations
under the Distribution Agreement concerning the distribution of the shares.
These obligations and the compensation the Distributor receives are described
above in the sections titled "Principal Underwriter" and "Rule 12b-1 Plans."
 
XI. CALCULATION OF PERFORMANCE DATA
- --------------------------------------------------------------------------------
 
   
    The Fund's current yield for the seven days ending January 31, 1999 was
3.90%. The effective annual yield on January 31, 1999, was 3.98% assuming daily
compounding.
    
 
    The Fund's annualized current yield, as may be quoted from time to time in
advertisements and other communications to shareholders and potential investors,
is computed by determining, for a stated seven-day period, the net change,
exclusive of capital changes and including the value of additional shares
purchased with dividends and any dividends declared therefrom (which reflect
deductions of all expenses of the Fund such as management fees), in the value of
a hypothetical pre-existing account having a balance of one share at the
beginning of the period, and dividing the difference by the value of the account
at the beginning of the base period to obtain the base period return, and then
multiplying the base period return by (365/7).
 
    The Fund's annualized effective yield, as may be quoted from time to time in
advertisements and other communications to shareholders and potential investors,
is computed by determining (for the same stated seven-day period as for the
current yield), the net change, exclusive of capital changes and including the
value of additional shares purchased with dividends and any dividends declared
therefrom (which reflect deductions of all expenses of the Fund such as
management fees), in the value of a hypothetical pre-existing account having a
balance of one share at the beginning of the period, and dividing the difference
by the value of the account at the beginning of the base period to obtain the
base period return, and then compounding the base period return by adding 1,
raising the sum to a power equal to 365 divided by 7, and subtracting 1 from the
result.
 
    The yields quoted in any advertisement or other communication should not be
considered a representation of the yields of the Fund in the future since the
yield is not fixed. Actual yields will depend not only on the type, quality and
maturities of the investments held by the Fund and changes in interest rates on
such investments, but also on changes in the Fund's expenses during the period.
 
    Yield information may be useful in reviewing the performance of the Fund and
for providing a basis for comparison with other investment alternatives.
However, unlike bank deposits or other investments which typically pay a fixed
yield for a stated period of time, the Fund's yield fluctuates.
 
    The Fund may also advertise the growth of hypothetical investments of
$10,000, $50,000 and $100,000 in shares of the Fund by adding the sum of all
distributions on 10,000, 50,000 or 100,000
 
                                       24
<PAGE>
   
shares of the Fund since inception to $10,000, $50,000 and $100,000, as the case
may be. Investments of $10,000, $50,000 and $100,000 in the Fund at inception
(February 17, 1982) would have grown to $26,930, $134,650 and $269,300,
respectively, at January 31, 1999.
    
 
XII. FINANCIAL STATEMENTS
- --------------------------------------------------------------------------------
 
   
    EXPERTS.  The financial statements of the Fund for the fiscal year ended
January 31, 1999 included in the PROSPECTUS and incorporated by reference in
this STATEMENT OF ADDITIONAL INFORMATION have been so included and incorporated
in reliance on the report of PricewaterhouseCoopers LLP, independent
accountants, given on the authority of said firm as experts in auditing and
accounting.
    
 
                                     *****
 
    This STATEMENT OF ADDITIONAL INFORMATION and the PROSPECTUS do not contain
all of the information set forth in the REGISTRATION STATEMENT the Fund has
filed with the SEC. The complete REGISTRATION STATEMENT may be obtained from the
SEC.
 
                                       25
<PAGE>

            MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST

                               PART C OTHER INFORMATION

Item 23.  EXHIBITS

       2.   Amended and Restated By-Laws of the Registrant dated January 28,
            1999.

       6.  Retirement Plan for Non-Interested Trustees or Directors.

      10.  Consent of Independent Accountants.

      14.  Financial Data Schedule.

      All other exhibits were previously filed via EDGAR and are hereby
      incorporated by reference.

Item 24.  PERSONS CONTROLLED BY OR UNDER COMMON CONTROL WITH THE FUND

          None

Item 25.  INDEMNIFICATION

     Pursuant to Section 5.3 of the Registrant's Declaration of Trust and under
Section 4.8 of the Registrant's By-Laws, the indemnification of the Registrant's
trustees, officers, employees and agents is permitted if it is determined that
they acted under the belief that their actions were in or not opposed to the
best interest of the Registrant, and, with respect to any criminal proceeding,
they had reasonable cause to believe their conduct was not unlawful.  In
addition, indemnification is permitted only if it is determined that the actions
in question did not render them liable by reason of willful misfeasance, bad
faith or gross negligence in the performance of their duties or by reason of
reckless disregard of their obligations and duties to the Registrant.  Trustees,
officers, employees and agents will be indemnified for the expense of litigation
if it is determined that they are entitled to indemnification against any
liability established in such litigation.  The Registrant may also advance money
for these expenses provided that they give their undertakings to repay the
Registrant unless their conduct is later determined to permit indemnification.

     Pursuant to Section 5.2 of the Registrant's Declaration of Trust and
paragraph 7 of the Registrant's Investment Management Agreement, neither the
Investment Manager nor any trustee, officer, employee or agent of the Registrant
shall be liable for any action or failure to act, except in the case of bad
faith, willful misfeasance, gross negligence or reckless disregard of duties to
the Registrant.

     Insofar as indemnification for liabilities arising under the Securities Act
of 1933 (the "Act") may be permitted to trustees, officers and controlling
persons of the Registrant pursuant to the foregoing provisions or otherwise, the
Registrant has been advised that in the opinion of the  Securities and Exchange
Commission such indemnification is against public policy as expressed in the Act
and is, therefore, unenforceable.  In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a trustee, officer, or controlling person of the Registrant
in connection with the successful defense of any action, suit or proceeding) is
asserted against the Registrant by


<PAGE>

such trustee, officer or controlling person in connection with the shares being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Act, and will be governed by the final adjudication
of such issue.

     The Registrant hereby undertakes that it will apply the indemnification
provision of its by-laws in a manner consistent with Release 11330 of the
Securities and Exchange Commission under the Investment Company Act of 1940, so
long as the interpretation of Sections 17(h) and 17(i) of such Act remains in
effect.

     Registrant, in conjunction with the Investment Manager, Registrant's
Trustees, and other registered investment management companies managed by the
Investment Manager, maintains insurance on behalf of any person who is or was a
Trustee, officer, employee, or agent of Registrant, or who is or was serving at
the request of Registrant as a trustee, director, officer, employee or agent of
another trust or corporation, against any liability asserted against him and
incurred by him or arising out of his position.  However, in no event will
Registrant maintain insurance to indemnify any such person for any act for which
Registrant itself is not permitted to indemnify him.

Item 26.  BUSINESS AND OTHER CONNECTIONS OF INVESTMENT ADVISOR

     See "The Fund and Its Management" in the Prospectus regarding the business
of the investment advisor.  The following information is given regarding
officers of Morgan Stanley Dean Witter Advisors Inc. ("MSDW Advisors").  MSDW
Advisors is a wholly-owned subsidiary of Morgan Stanley Dean Witter & Co.  The
principal address of the Morgan Stanley Dean Witter Funds is Two World Trade
Center, New York, New York 10048.

     The term "Morgan Stanley Dean Witter Funds" refers to the following
registered investment companies:

CLOSED-END INVESTMENT COMPANIES
- -------------------------------
(1)   Morgan Stanley Dean Witter California Insured Municipal Income Trust
(2)   Morgan Stanley Dean Witter California Quality Municipal Securities
(3)   Morgan Stanley Dean Witter Government Income Trust
(4)   Morgan Stanley Dean Witter High Income Advantage Trust
(5)   Morgan Stanley Dean Witter High Income Advantage Trust II
(6)   Morgan Stanley Dean Witter High Income Advantage Trust III
(7)   Morgan Stanley Dean Witter Income Securities Inc.
(8)   Morgan Stanley Dean Witter Insured California Municipal Securities
(9)   Morgan Stanley Dean Witter Insured Municipal Bond Trust
(10)  Morgan Stanley Dean Witter Insured Municipal Income Trust
(11)  Morgan Stanley Dean Witter Insured Municipal Securities
(12)  Morgan Stanley Dean Witter Insured Municipal Trust
(13)  Morgan Stanley Dean Witter Municipal Income Opportunities Trust
(14)  Morgan Stanley Dean Witter Municipal Income Opportunities Trust II
(15)  Morgan Stanley Dean Witter Municipal Income Opportunities Trust III
(16)  Morgan Stanley Dean Witter Municipal Income Trust
(17)  Morgan Stanley Dean Witter Municipal Income Trust II
(18)  Morgan Stanley Dean Witter Municipal Income Trust III
(19)  Morgan Stanley Dean Witter Municipal Premium Income Trust


<PAGE>

(20)  Morgan Stanley Dean Witter New York Quality Municipal Securities
(21)  Morgan Stanley Dean Witter Prime Income Trust
(22)  Morgan Stanley Dean Witter Quality Municipal Income Trust
(23)  Morgan Stanley Dean Witter Quality Municipal Investment Trust
(24)  Morgan Stanley Dean Witter Quality Municipal Securities

OPEN-END INVESTMENT COMPANIES
- -----------------------------
(1)   Active Assets California Tax-Free Trust
(2)   Active Assets Government Securities Trust
(3)   Active Assets Money Trust
(40   Active Assets Tax-Free Trust
(5)   Morgan Stanley Dean Witter Aggressive Equity Fund
(6)   Morgan Stanley Dean Witter American Value Fund
(7)   Morgan Stanley Dean Witter Balanced Growth Fund
(8)   Morgan Stanley Dean Witter Balanced Income Fund
(9)   Morgan Stanley Dean Witter California Tax-Free Daily Income Trust
(10)  Morgan Stanley Dean Witter California Tax-Free Income Fund
(11)  Morgan Stanley Dean Witter Capital Growth Securities
(12)  Morgan Stanley Dean Witter Competitive Edge Fund, "BEST IDEAS PORTFOLIO"
(13)  Morgan Stanley Dean Witter Convertible Securities Trust
(14)  Morgan Stanley Dean Witter Developing Growth Securities Trust
(15)  Morgan Stanley Dean Witter Diversified Income Trust
(16)  Morgan Stanley Dean Witter Dividend Growth Securities Inc.
(17)  Morgan Stanley Dean Witter Equity Fund
(18)  Morgan Stanley Dean Witter European Growth Fund Inc.
(19)  Morgan Stanley Dean Witter Federal Securities Trust
(20)  Morgan Stanley Dean Witter Financial Services Trust
(21)  Morgan Stanley Dean Witter Fund of Funds
(22)  Morgan Stanley Dean Witter Global Dividend Growth Securities
(23)  Morgan Stanley Dean Witter Global Utilities Fund
(24)  Morgan Stanley Dean Witter Growth Fund
(25)  Morgan Stanley Dean Witter Hawaii Municipal Trust
(26)  Morgan Stanley Dean Witter Health Sciences Trust
(27)  Morgan Stanley Dean Witter High Yield Securities Inc.
(28)  Morgan Stanley Dean Witter Income Builder Fund
(29)  Morgan Stanley Dean Witter Information Fund
(30)  Morgan Stanley Dean Witter Intermediate Income Securities
(31)  Morgan Stanley Dean Witter International SmallCap Fund
(32)  Morgan Stanley Dean Witter Japan Fund
(33)  Morgan Stanley Dean Witter Limited Term Municipal Trust
(34)  Morgan Stanley Dean Witter Liquid Asset Fund Inc.
(35)  Morgan Stanley Dean Witter Market Leader Trust
(36)  Morgan Stanley Dean Witter Mid-Cap Dividend Growth Securities
(37)  Morgan Stanley Dean Witter Mid-Cap Growth Fund
(38)  Morgan Stanley Dean Witter Multi-State Municipal Series Trust
(39)  Morgan Stanley Dean Witter Natural Resource Development Securities Inc.
(40)  Morgan Stanley Dean Witter New York Municipal Money Market Trust
(41)  Morgan Stanley Dean Witter New York Tax-Free Income Fund
(42)  Morgan Stanley Dean Witter Pacific Growth Fund Inc.
(43)  Morgan Stanley Dean Witter Precious Metals and Minerals Trust
(44)  Morgan Stanley Dean Witter Real Estate Fund


<PAGE>

(45)  Morgan Stanley Dean Witter S&P 500 Index Fund
(46)  Morgan Stanley Dean Witter S&P 500 Select Fund
(47)  Morgan Stanley Dean Witter Select Dimensions Investment Series
(48)  Morgan Stanley Dean Witter Select Municipal Reinvestment Fund
(49)  Morgan Stanley Dean Witter Short-Term Bond Fund
(50)  Morgan Stanley Dean Witter Short-Term U.S. Treasury Trust
(51)  Morgan Stanley Dean Witter Special Value Fund
(52)  Morgan Stanley Dean Witter Strategist Fund
(53)  Morgan Stanley Dean Witter Tax-Exempt Securities Trust
(54)  Morgan Stanley Dean Witter Tax-Free Daily Income Trust
(55)  Morgan Stanley Dean Witter U.S. Government Money Market Trust
(56)  Morgan Stanley Dean Witter U.S. Government Securities Trust
(57)  Morgan Stanley Dean Witter Utilities Fund
(58)  Morgan Stanley Dean Witter Value-Added Market Series
(59)  Morgan Stanley Dean Witter Value Fund
(60)  Morgan Stanley Dean Witter Variable Investment Series
(61)  Morgan Stanley Dean Witter World Wide Income Trust

The term "TCW/DW Funds" refers to the following registered investment companies:

OPEN-END INVESTMENT COMPANIES
- -----------------------------
(1)   TCW/DW Emerging Markets Opportunities Trust
(2)   TCW/DW Global Telecom Trust
(3)   TCW/DW Income and Growth Fund
(4)   TCW/DW Latin American Growth Fund
(5)   TCW/DW Mid-Cap Equity Trust
(6)   TCW/DW North American Government Income Trust
(7)   TCW/DW Small Cap Growth Fund
(8)   TCW/DW Total Return Trust

CLOSED-END INVESTMENT COMPANIES
- -------------------------------
(1)   TCW/DW Term Trust 2000
(2)   TCW/DW Term Trust 2002
(3)   TCW/DW Term Trust 2003

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        ------------------------------------------------

Mitchell M. Merin             President and Chief Operating Officer of Asset
President, Chief              Management of Morgan Stanley Dean Witter & Co.
Executive Officer and         ("MSDW); Chairman and Director of Morgan Stanley
Director                      Dean Witter Distributors Inc. ("MSDW
                              Distributors") and Morgan Stanley Dean Witter
                              Trust FSB ("MSDW Trust"); President, Chief
                              Executive Officer and Director of Morgan Stanley
                              Dean Witter Services Company Inc. ("MSDW
                              Services"); Vice President of the Morgan Stanley
                              Dean Witter Funds, TCW/DW Funds and Discover
                              Brokerage Index Series; Executive Vice President
                              and Director of Dean Witter Reynolds Inc. ("DWR");
                              Director of various MSDW subsidiaries.


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        ------------------------------------------------

Thomas C. Schneider           Executive Vice President and Chief Strategic and
Executive Vice                Administrative Officer of MSDW; Executive Vice
President and  Chief          President and Chief Financial Officer of MSDW
Financial Officer             Services; Director of DWR and MSDW.

Joseph J. McAlinden           Vice President of the Morgan Stanley Dean Witter
Executive Vice President      Funds and Discover Brokerage Index Series; and
Chief Investment              Director of MSDW Trust.
Officer


Ronald E. Robison             Executive Vice President , Chief Administrative
Executive Vice President,     Officer and Director of MSDW Services; Vice Chief
Administrative                President of the Morgan Stanley Dean Witter Funds,
Officer and Director          TCW/DW Funds and Discover Brokerage Index Series

Edward C. Oelsner, III
Executive Vice President

Barry Fink                    Assistant Secretary of DWR; Senior Vice President,
Senior Vice President,        Secretary, General Counsel and Director of MSDW
Secretary, General            Services; Senior Vice President, Assistant Counsel
and Director                  Secretary and Assistant General Counsel of MSDW
                              Distributors; Vice President, Secretary and
                              General Counsel of the Morgan Stanley Dean Witter
                              Funds, TCW/DW Funds and Discover Brokerage Index
                              Series.

Peter M. Avelar               Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Mark Bavoso                   Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Douglas Brown
Senior Vice President

Rosalie Clough
Senior Vice President
and Director of Marketing

Richard Felegy
Senior Vice President

Edward F. Gaylor              Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Robert S. Giambrone           Senior Vice President of MSDW Services, MSDW
Senior Vice President         Distributors and MSDW Trust and Director of MSDW
                              Trust; Vice President of the Morgan Stanley Dean
                              Witter Funds, TCW/DW Funds and Discover Brokerage
                              Index Series.

Rajesh K. Gupta               Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Kenton J. Hinchliffe          Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds and Discover Brokerage Index Series.

Kevin Hurley                  Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Margaret Iannuzzi
Senior Vice President

Jenny Beth Jones              Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Michelle Kaufman              Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

John B. Kemp, III             President of MSDW Distributors.
Senior Vice President

Anita H. Kolleeny             Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Jonathan R. Page              Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Ira N. Ross                   Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Guy G. Rutherfurd, Jr.        Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Rochelle G. Siegel            Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

James Solloway
Senior Vice President

Jayne M. Stevlingson          Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Paul D. Vance                 Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Elizabeth A. Vetell
Senior Vice President
and Director of Shareholder
Communication

James F. Willison             Vice President of various Morgan Stanley Dean
Senior Vice President         Witter Funds.

Frank Bruttomesso             First Vice President and Assistant Secretary of
First Vice President and      MSDW Services; Assistant Secretary of the Morgan
Assistant Secretary           Stanley Dean Witter Funds, TCW/DW Funds and
                              Discover Brokerage Index Series.

Toby Burroughs
First Vice President

Thomas F. Caloia              First Vice President and Assistant Treasurer of
First Vice President          MSDW Services; Assistant Treasurer of MSDW
and Assistant                 Distributors; Treasurer and Chief Financial and
Treasurer                     Accounting Officer of the Morgan Stanley Dean
                              Witter Funds, TCW/DW Funds and Discover Brokerage
                              Index Series..

Thomas Chronert
First Vice President

Marilyn K. Cranney            Assistant Secretary of DWR; First Vice President
First Vice President          and Assistant Secretary of MSDW Services; and
Assistant Secretary           Assistant Secretary of the Morgan Stanley Dean
                              Witter Funds, TCW/DW Funds and Discover Brokerage
                              Index Series.

Salvatore DeSteno             Vice President of MSDW Services.
First Vice President

Peter W. Gurman
First Vice President

Michael Interrante            First Vice President and Controller of MSDW First
Vice President                Services; Assistant Treasurer of MSDW and
Controller                    Distributors; First Vice President and Treasurer
                              of MSDW Trust.

David Johnson
First Vice President


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Stanley Kapica
First Vice President

LouAnne D. McInnis            First Vice President and Assistant Secretary of
First Vice President and      MSDW Services; Assistant Secretary of the Morgan
Assistant Secretary           Stanley Dean Witter Funds, TCW/DW Funds and
                              Discover Brokerage Index Series.

Carsten Otto                  First Vice President and Assistant Secretary of
First Vice President          MSDW Services; Assistant Secretary of the Morgan
and Assistant Secretary       Stanley Dean Witter Funds, TCW/DW Funds and
                              Discover Brokerage Index Series.

Ruth Rossi                    First Vice President and Assistant Secretary of
First Vice President and      MSDW Services; Assistant Secretary of the Morgan
Assistant Secretary           Stanley Dean Witter Funds, TCW/DW Funds and
                              Discover Brokerage Index Series.

James P. Wallin
First Vice President

Robert Zimmerman
First Vice President

Dale Albright
Vice President

Joan G. Allman
Vice President

Andrew Arbenz
Vice President

Joseph Arcieri                Vice President of various Morgan Stanley Dean Vice
President                     Witter Funds.

Armon Bar-Tur
Vice President

Nancy Belza
Vice President

Maurice Bendrihem
Vice President and
Assistant Controller


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Dale Boetcher
Vice President

Ronald Caldwell
Vice President

Joseph Cardwell
Vice President

Liam Carroll
Vice President

Philip Casparius
Vice President

Aaron Clark
Vice President

William Connerly
Vice President

David Dineen
Vice President

Michael Durbin
Vice President

Sheila Finnerty
Vice President

Jeffrey D. Geffen
Vice President

Sandra Gelpieryn
Vice President

Michael Geringer
Vice President

Gail Gerrity
Vice President

Ellen Gold
Vice President

Stephen Greenhut
Vice President


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Matthew Haynes                Vice President of various Morgan Stanley Dean Vice
President                     Witter Funds.

Peter Hermann                 Vice President of various Morgan Stanley Dean Vice
President                     Witter Funds.

David Hoffman
Vice President

Christopher Jones
Vice President

Kevin Jung
Vice President

Carol Espejo Kane
Vice President

Nancy Kennedy
Vice President

Doug Ketterer
Vice President

Paula LaCosta                 Vice President of various Morgan Stanley Dean Vice
President                     Witter Funds.

Kimberly LaHart
Vice President

Thomas Lawlor
Vice President

Todd Lebo                     Vice President and Assistant Secretary of MSDW
Vice President and            Services; Assistant Secretary of the Morgan
Assistant Secretary           Stanley Dean Witter Funds, TCW/DW Funds and
                              Discover Brokerage Index Series.

Gerard J. Lian                Vice President of various Morgan Stanley Dean Vice
President                     Witter Funds.

Nancy Login
Vice President

Sharon Loquercio
Vice President


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Steven MacNamara
Vice President

Catherine Maniscalco          Vice President of Morgan Stanley Dean Witter
Vice President                Natural Resource Development Securities Inc.

Albert McGarity
Vice President

Teresa McRoberts              Vice President of Morgan Stanley Dean Witter S&P
Vice President                500 Select Fund.

Mark Mitchell
Vice President

Julie Morrone
Vice President

Mary Beth Mueller
Vice President

David Myers                   Vice President of Morgan Stanley Dean Witter
Vice President                Natural Resource Development Securities Inc.

Richard Norris
Vice President

George Paoletti               Vice President of Morgan Stanley Dean Witter
Vice President                Information Fund.

Anne Pickrell                 Vice President of various  Morgan Stanley Dean
Vice President                Witter Funds.

Dawn Rorke
Vice President

John Roscoe                   Vice President of Morgan Stanley Dean Witter
Vice President                Real Estate Fund

Hugh Rose
Vice President

Robert Rossetti               Vice President of various Morgan Stanley Dean
Vice President                Witter Funds.

Carl F. Sadler
Vice President


<PAGE>

NAME AND POSITION WITH        OTHER SUBSTANTIAL BUSINESS, PROFESSION, VOCATION
MORGAN STANLEY DEAN           OR EMPLOYMENT, INCLUDING NAME, PRINCIPAL ADDRESS
WITTER ADVISORS INC.          AND NATURE OF CONNECTION
- ----------------------        -------------------------------------------------

Deborah Santaniello
Vice President

Patrice Saunders
Vice President

Howard A. Schloss             Vice President of Morgan Stanley Dean Witter
Vice President                Federal Securities Trust.

Peter J. Seeley               Vice President of various Morgan Stanley Dean
Vice President                Witter Funds.

Robert Stearns
Vice President

Naomi Stein
Vice President

Michael Strayhorn
Vice President

Kathleen H. Stromberg         Vice President of various Morgan Stanley Dean
Vice President                Witter Funds.

Marybeth Swisher
Vice President

Michael Thayer
Vice President

Robert Vanden Assem
Vice President

Alice Weiss                   Vice President of various Morgan Stanley Dean
Vice President                Witter Funds.

John Wong
Vice President

Item 27.  PRINCIPAL UNDERWRITERS

(a)    Morgan Stanley Dean Witter Distributors Inc. ("MSDW Distributors"), a
Delaware corporation, is the principal underwriter of the Registrant. MSDW
Distributors is also the principal underwriter of the following investment
companies:

(1)    Active Assets California Tax-Free Trust
(2)    Active Assets Government Securities Trust


<PAGE>

(3)    Active Assets Money Trust
(4)    Active Assets Tax-Free Trust
(5)    Morgan Stanley Dean Witter Aggressive Equity Fund
(6)    Morgan Stanley Dean Witter American Value Fund
(7)    Morgan Stanley Dean Witter Balanced Growth Fund
(8)    Morgan Stanley Dean Witter Balanced Income Fund
(9)    Morgan Stanley Dean Witter California Tax-Free Daily Income Trust
(10)   Morgan Stanley Dean Witter California Tax-Free Income Fund
(11)   Morgan Stanley Dean Witter Capital Growth Securities
(12)   Morgan Stanley Dean Witter Competitive Edge Fund, "BEST IDEAS PORTFOLIO"
(13)   Morgan Stanley Dean Witter Convertible Securities Trust
(14)   Morgan Stanley Dean Witter Developing Growth Securities Trust
(15)   Morgan Stanley Dean Witter Diversified Income Trust
(16)   Morgan Stanley Dean Witter Dividend Growth Securities Inc.
(17)   Morgan Stanley Dean Witter Equity Fund
(18)   Morgan Stanley Dean Witter European Growth Fund Inc.
(19)   Morgan Stanley Dean Witter Federal Securities Trust
(20)   Morgan Stanley Dean Witter Financial Services Trust
(21)   Morgan Stanley Dean Witter Fund of Funds
(22)   Morgan Stanley Dean Witter Global Dividend Growth Securities
(23)   Morgan Stanley Dean Witter Global Utilities Fund
(24)   Morgan Stanley Dean Witter Growth Fund
(25)   Morgan Stanley Dean Witter Hawaii Municipal Trust
(26)   Morgan Stanley Dean Witter Health Sciences Trust
(27)   Morgan Stanley Dean Witter High Yield Securities Inc.
(28)   Morgan Stanley Dean Witter Income Builder Fund
(29)   Morgan Stanley Dean Witter Information Fund
(30)   Morgan Stanley Dean Witter Intermediate Income Securities
(31)   Morgan Stanley Dean Witter International SmallCap Fund
(32)   Morgan Stanley Dean Witter Japan Fund
(33)   Morgan Stanley Dean Witter Limited Term Municipal Trust
(34)   Morgan Stanley Dean Witter Liquid Asset Fund Inc.
(35)   Morgan Stanley Dean Witter Market Leader Trust
(36)   Morgan Stanley Dean Witter Mid-Cap Dividend Growth Securities
(37)   Morgan Stanley Dean Witter Mid-Cap Growth Fund
(38)   Morgan Stanley Dean Witter Multi-State Municipal Series Trust
(39)   Morgan Stanley Dean Witter Natural Resource Development Securities Inc.
(40)   Morgan Stanley Dean Witter New York Municipal Money Market Trust
(41)   Morgan Stanley Dean Witter New York Tax-Free Income Fund
(42)   Morgan Stanley Dean Witter Pacific Growth Fund Inc.
(43)   Morgan Stanley Dean Witter Precious Metals and Minerals Trust
(44)   Morgan Stanley Dean Witter Prime Income Trust
(45)   Morgan Stanley Dean Witter Real Estate Fund
(46)   Morgan Stanley Dean Witter S&P 500 Index Fund
(47)   Morgan Stanley Dean Witter S&P 500 Select Fund
(48)   Morgan Stanley Dean Witter Short-Term Bond Fund
(49)   Morgan Stanley Dean Witter Short-Term U.S. Treasury Trust
(50)   Morgan Stanley Dean Witter Special Value Fund
(51)   Morgan Stanley Dean Witter Strategist Fund
(52)   Morgan Stanley Dean Witter Tax-Exempt Securities Trust
(53)   Morgan Stanley Dean Witter Tax-Free Daily Income Trust


<PAGE>

(54)   Morgan Stanley Dean Witter U.S. Government Money Market Trust
(55)   Morgan Stanley Dean Witter U.S. Government Securities Trust
(56)   Morgan Stanley Dean Witter Utilities Fund
(57)   Morgan Stanley Dean Witter Value-Added Market Series
(58)   Morgan Stanley Dean Witter Value Fund
(59)   Morgan Stanley Dean Witter Variable Investment Series
(60)   Morgan Stanley Dean Witter World Wide Income Trust
(1)    TCW/DW Emerging Markets Opportunities Trust
(2)    TCW/DW Global Telecom Trust
(3)    TCW/DW Income and Growth
(4)    TCW/DW Latin American Growth Fund
(5)    TCW/DW Mid-Cap Equity Trust
(6)    TCW/DW North American Government Income Trust
(7)    TCW/DW Small Cap Growth Fund
(8)    TCW/DW Total Return Trust

(b)    The following information is given regarding directors and officers of
MSDW Distributors not listed in Item 26 above.  The principal address of MSDW
Distributors is Two World Trade Center, New York, New York 10048.  Other than
Mr. Purcell, who is a Trustee of the Registrant, none of the following persons
has any position or office with the Registrant.

NAME                     POSITIONS AND OFFICE WITH MSDW DISTRIBUTORS
- ----                     -------------------------------------------

Christine Edwards        Executive Vice President, Secretary, Director and Chief
                         Legal Officer.

Michael T. Gregg         Vice President and Assistant Secretary.

James F. Higgins         Director

Fredrick K. Kubler       Senior Vice President, Assistant Secretary and Chief
                         Compliance Officer.

Philip J. Purcell        Director

John Schaeffer           Director

Charles Vidala           Senior Vice President and Financial Principal.

Item 28.  LOCATION OF ACCOUNTS AND RECORDS

     All accounts, books and other documents required to be maintained by
Section 31(a) of the Investment Company Act of 1940 and the Rules thereunder are
maintained by the Investment Manager at its offices, except records relating to
holders of shares issued by the Registrant, which are maintained by the
Registrant's Transfer Agent, at its place of business as shown in the
prospectus.

Item 29.  MANAGEMENT SERVICES

     Registrant is not a party to any such management-related service contract.


<PAGE>


Item 30.  UNDERTAKINGS

     None.

<PAGE>

                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933 and the
Investment Company Act of 1940, the Registrant certifies that it meets all
of the requirements for effectiveness of this Registration Statement pursuant
to Rule 485(b) under the Securities Act of 1933 and has duly caused this
Post-Effective Amendment to the Registration Statement to be signed on its
behalf by the undersigned, thereunto duly authorized, in the City of New York
and State of New York on the 26th day of March, 1999.

   MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST

                                        By  /s/ Barry Fink
                                           -------------------------------------
                                                Barry Fink
                                                Vice President and Secretary

     Pursuant to the requirements of the Securities Act of 1933, this
Post-Effective Amendment No. 20 has been signed below by the following persons
in the capacities and on the dates indicated.

          Signatures                    Title                         Date
          ----------                    -----                         ----

(1) Principal Executive Officer         President, Chief
                                        Executive Officer,
                                        Trustee and Chairman

By  /s/ Charles A. Fiumefreddo                                        03/26/99
   --------------------------------
        Charles A. Fiumefreddo

(2) Principal Financial Officer         Treasurer and Principal
                                        Accounting Officer

By  /s/ Thomas F. Caloia                                              03/26/99
   --------------------------------
        Thomas F. Caloia

(3) Majority of the Trustees

    Charles A. Fiumefreddo (Chairman)
    Philip J. Purcell

By  /s/ Barry Fink                                                    03/26/99
   --------------------------------
        Barry Fink
        Attorney-in-Fact

    Michael Bozic        Manuel H. Johnson
    Edwin J. Garn        Michael E. Nugent
    John R. Haire        John L. Schroeder
    Wayne E. Hedien


By  /s/ David M. Butowsky                                             03/26/99
   --------------------------------
        David M. Butowsky
        Attorney-in-Fact


<PAGE>

          MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST

                                 EXHIBIT INDEX


      2.  Amended and Restated By-Laws of the Registrant dated January 28, 1999.

      6.  Retirement Plan for Non-Interested Trustees or Directors.

     10.  Consent of Independent Accountants.

     14.  Financial Data Schedule.



<PAGE>

                                    BY-LAWS

                                       OF

                           MORGAN STANLEY DEAN WITTER
                       U.S. GOVERNMENT MONEY MARKET TRUST

                  AMENDED AND RESTATED AS OF JANUARY 28, 1999

                                   ARTICLE I

                                  DEFINITIONS

     The terms "COMMISSION," "DECLARATION," "DISTRIBUTOR," "INVESTMENT ADVISER,"
"MAJORITY SHAREHOLDER VOTE," "1940 ACT," "SHAREHOLDER," "SHARES," "TRANSFER
AGENT," "TRUST," "TRUST PROPERTY," and "TRUSTEES" have the respective meanings
given them in the Declaration of Trust of Morgan Stanley Dean Witter U.S.
Government Money Market Trust dated November 18, 1981, as amended from time to
time.

                                   ARTICLE II

                                    OFFICES

     SECTION 2.1. PRINCIPAL OFFICE. Until changed by the Trustees, the principal
office of the Trust in the Commonwealth of Massachusetts shall be in the City of
Boston, County of Suffolk.

     SECTION 2.2. OTHER OFFICES. In addition to its principal office in the
Commonwealth of Massachusetts, the Trust may have an office or offices in the
City of New York, State of New York, and at such other places within and without
the Commonwealth as the Trustees may from time to time designate or the business
of the Trust may require.

                                  ARTICLE III

                             SHAREHOLDERS' MEETINGS

     SECTION 3.1. PLACE OF MEETINGS. Meetings of Shareholders shall be held at
such place, within or without the Commonwealth of Massachusetts, as may be
designated from time to time by the Trustees.

     SECTION 3.2. MEETINGS. Meetings of Shareholders of the Trust shall be held
whenever called by the Trustees or the President of the Trust and whenever
election of a Trustee or Trustees by Shareholders is required by the provisions
of Section 16(a) of the 1940 Act, for that purpose. Meetings of Shareholders
shall also be called by the Secretary upon the written request of the holders of
Shares entitled to vote not less than twenty-five percent (25%) of all the votes
entitled to be cast at such meeting. Such request shall state the purpose or
purposes of such meeting and the matters proposed to be acted on thereat. The
Secretary shall inform such Shareholders of the reasonable estimated cost of
preparing and mailing such notice of the meeting, and upon payment to the Trust
of such costs, the Secretary shall give notice stating the purpose or purposes
of the meeting to all entitled to vote at such meeting. No meeting need be
called upon the request of the holders of Shares entitled to cast less than a
majority of all votes entitled to be cast at such meeting, to consider any
matter which is substantially the same as a matter voted upon at any meeting of
Shareholders held during the preceding twelve months.

     SECTION 3.3. NOTICE OF MEETINGS. Written or printed notice of every
Shareholders' meeting stating the place, date, and purpose or purposes thereof,
shall be given by the Secretary not less than ten (10) nor more than ninety (90)
days before such meeting to each Shareholder entitled to vote at such meeting.
Such notice shall be deemed to be given when deposited in the United States
mail, postage prepaid, directed to the Shareholder at his address as it appears
on the records of the Trust.

     SECTION 3.4. QUORUM AND ADJOURNMENT OF MEETINGS. Except as otherwise
provided by law, by the Declaration or by these By-Laws, at all meetings of
Shareholders, the holders of a majority of the Shares issued and outstanding and
entitled to vote thereat, present in person or represented by proxy, shall be

<PAGE>

requisite and shall constitute a quorum for the transaction of business. In the
absence of a quorum, the Shareholders present or represented by proxy and
entitled to vote thereat shall have the power to adjourn the meeting from time
to time. The Shareholders present in person or represented by proxy at any
meeting and entitled to vote thereat also shall have the power to adjourn the
meeting from time to time if the vote required to approve or reject any proposal
described in the original notice of such meeting is not obtained (with proxies
being voted for or against adjournment consistent with the votes for and against
the proposal for which the required vote has not been obtained). The affirmative
vote of the holders of a majority of the Shares then present in person or
represented by proxy shall be required to adjourn any meeting. Any adjourned
meeting may be reconvened without further notice or change in record date. At
any reconvened meeting at which a quorum shall be present, any business may be
transacted that might have been transacted at the meeting as originally called.

     SECTION 3.5.  VOTING RIGHTS, PROXIES. At each meeting of Shareholders, each
holder of record of Shares entitled to vote thereat shall be entitled to one
vote in person or by proxy for each Share of beneficial interest of the Trust
and for the fractional portion of one vote for each fractional Share entitled to
vote so registered in his or her name on the records of the Trust on the date
fixed as the record date for the determination of Shareholders entitled to vote
at such meeting. Without limiting the manner in which a Shareholder may
authorize another person or persons to act for such Shareholder as proxy
pursuant hereto, the following shall constitute a valid means by which a
Shareholder may grant such authority:

     (i) A Shareholder may execute a writing authorizing another person or
     persons to act for such Shareholder as proxy. Execution may be accomplished
     by the Shareholder or such Shareholder's authorized officer, director,
     employee, attorney-in-fact or another agent signing such writing or causing
     such person's signature to be affixed to such writing by any reasonable
     means including, but not limited to, by facsimile or telecopy signature. No
     written evidence of authority of a Shareholder's authorized officer,
     director, employee, attorney-in-fact or other agent shall be required; and

     (ii) A Shareholder may authorize another person or persons to act for such
     Shareholder as proxy by transmitting or authorizing the transmission of a
     telegram or cablegram or by other means of telephonic, electronic or
     computer transmission to the person who will be the holder of the proxy or
     to a proxy solicitation firm, proxy support service organization or like
     agent duly authorized by the person who will be the holder of the proxy to
     receive such transmission, provided that any such telegram or cablegram or
     other means of telephonic, electronic or computer transmission must either
     set forth or be submitted with information from which it can be determined
     that the telegram, cablegram or other transmission was authorized by the
     Shareholder.

No proxy shall be valid after eleven months from its date, unless otherwise
provided in the proxy. At all meetings of Shareholders, unless the voting is
conducted by inspectors, all questions relating to the qualification of voters
and the validity of proxies and the acceptance or rejection of votes shall be
decided by the chairman of the meeting. In determining whether a telegram,
cablegram or other electronic transmission is valid, the chairman or inspector,
as the case may be, shall specify the information upon which he or she relied.
Pursuant to a resolution of a majority of the Trustees, proxies may be solicited
in the name of one or more Trustees or Officers of the Trust. Proxy
solicitations may be made in writing or by using telephonic or other electronic
solicitation procedures that include appropriate methods of verifying the
identity of the Shareholder and confirming any instructions given thereby.

     SECTION 3.6. VOTE REQUIRED. Except as otherwise provided by law, by the
Declaration of Trust, or by these By-Laws, at each meeting of Shareholders at
which a quorum is present, all matters shall be decided by Majority Shareholder
Vote.

     SECTION 3.7. INSPECTORS OF ELECTION. In advance of any meeting of
Shareholders, the Trustees may appoint Inspectors of Election to act at the
meeting or any adjournment thereof. If Inspectors of Election are not so
appointed, the chairman of any meeting of Shareholders may, and on the request
of any Shareholder or his proxy shall, appoint Inspectors of Election of the
meeting. In case any person appointed as Inspector fails to appear or fails or
refuses to act, the vacancy may be filled by appointment made by the Trustees in
advance of the convening of the meeting or at the meeting by the person acting

                                        2
<PAGE>

as chairman. The Inspectors of Election shall determine the number of Shares
outstanding, the Shares represented at the meeting, the existence of a quorum,
the authenticity, validity and effect of proxies, shall receive votes, ballots
or consents, shall hear and determine all challenges and questions in any way
arising in connection with the right to vote, shall count and tabulate all votes
or consents, determine the results, and do such other acts as may be proper to
conduct the election or vote with fairness to all Shareholders. On request of
the chairman of the meeting, or of any Shareholder or his proxy, the Inspectors
of Election shall make a report in writing of any challenge or question or
matter determined by them and shall execute a certificate of any facts found by
them.

     SECTION 3.8. INSPECTION OF BOOKS AND RECORDS. Shareholders shall have such
rights and procedures of inspection of the books and records of the Trust as are
granted to Shareholders under Section 32 of the Business Corporation Law of the
Commonwealth of Massachusetts.

     SECTION 3.9. ACTION BY SHAREHOLDERS WITHOUT MEETING. Except as otherwise
provided by law, the provisions of these By-Laws relating to notices and
meetings to the contrary notwithstanding, any action required or permitted to be
taken at any meeting of Shareholders may be taken without a meeting if a
majority of the Shareholders entitled to vote upon the action consent to the
action in writing and such consents are filed with the records of the Trust.
Such consent shall be treated for all purposes as a vote taken at a meeting of
Shareholders.

     SECTION 3.10. PRESENCE AT MEETINGS. Presence at meetings of shareholders
requires physical attendance by the shareholder or his or her proxy at the
meeting site and does not encompass attendance by telephonic or other electronic
means.

                                   ARTICLE IV

                                    TRUSTEES

     SECTION 4.1. MEETINGS OF THE TRUSTEES. The Trustees may in their discretion
provide for regular or special meetings of the Trustees. Regular meetings of the
Trustees may be held at such time and place as shall be determined from time to
time by the Trustees without further notice. Special meetings of the Trustees
may be called at any time by the President and shall be called by the President
or the Secretary upon the written request of any two (2) Trustees.

     SECTION 4.2. NOTICE OF SPECIAL MEETINGS. Written notice of special meetings
of the Trustees, stating the place, date and time thereof, shall be given not
less than two (2) days before such meeting to each Trustee, personally, by
telegram, by mail, or by leaving such notice at his place of residence or usual
place of business. If mailed, such notice shall be deemed to be given when
deposited in the United States mail, postage prepaid, directed to the Trustee at
his address as it appears on the records of the Trust. Subject to the provisions
of the 1940 Act, notice or waiver of notice need not specify the purpose of any
special meeting.

     SECTION 4.3. TELEPHONE MEETINGS. Subject to the provisions of the 1940 Act,
any Trustee, or any member or members of any committee designated by the
Trustees, may participate in a meeting of the Trustees, or any such committee,
as the case may be, by means of a conference telephone or similar communications
equipment if all persons participating in the meeting can hear each other at the
same time. Participation in a meeting by these means constitutes presence in
person at the meeting.

     SECTION 4.4. QUORUM, VOTING AND ADJOURNMENT OF MEETINGS. At all meetings of
the Trustees, a majority of the Trustees shall be requisite to and shall
constitute a quorum for the transaction of business. If a quorum is present, the
affirmative vote of a majority of the Trustees present shall be the act of the
Trustees, unless the concurrence of a greater proportion is expressly required
for such action by law, the Declaration or these By-Laws. If at any meeting of
the Trustees there be less than a quorum present, the Trustees present thereat
may adjourn the meeting from time to time, without notice other than
announcement at the meeting, until a quorum shall have been obtained.

     SECTION 4.5. ACTION BY TRUSTEES WITHOUT MEETING. The provisions of these
By-Laws covering notices and meetings to the contrary notwithstanding, and
except as required by law, any action required or permitted to be taken at any
meeting of the Trustees may be taken without a meeting if a consent in

                                        3
<PAGE>

writing setting forth the action shall be signed by all of the Trustees entitled
to vote upon the action and such written consent is filed with the minutes of
proceedings of the Trustees.

     SECTION 4.6. EXPENSES AND FEES. Each Trustee may be allowed expenses, if
any, for attendance at each regular or special meeting of the Trustees, and each
Trustee who is not an officer or employee of the Trust or of its investment
manager or underwriter or of any corporate affiliate of any of said persons
shall receive for services rendered as a Trustee of the Trust such compensation
as may be fixed by the Trustees. Nothing herein contained shall be construed to
preclude any Trustee from serving the Trust in any other capacity and receiving
compensation therefor.

     SECTION 4.7.  EXECUTION OF INSTRUMENTS AND DOCUMENTS AND SIGNING OF
CHECKS AND OTHER OBLIGATIONS AND TRANSFERS. All instruments, documents and other
papers shall be executed in the name and on behalf of the Trust and all checks,
notes, drafts and other obligations for the payment of money by the Trust shall
be signed, and all transfer of securities standing in the name of the Trust
shall be executed, by the Chairman, the President, any Vice President or the
Treasurer or by any one or more officers or agents of the Trust as shall be
designated for that purpose by vote of the Trustees; notwithstanding the above,
nothing in this Section 4.7 shall be deemed to preclude the electronic
authorization, by designated persons, of the Trust's Custodian (as described
herein in Section 9.1) to transfer assets of the Trust, as provided for herein
in Section 9.1.

     SECTION 4.8. INDEMNIFICATION OF TRUSTEES, OFFICERS, EMPLOYEES AND AGENTS.
(a) The Trust shall indemnify any person who was or is a party or is threatened
to be made a party to any threatened, pending, or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (other than
an action by or in the right of the Trust) by reason of the fact that he is or
was a Trustee, officer, employee, or agent of the Trust. The indemnification
shall be against expenses, including attorneys' fees, judgments, fines, and
amounts paid in settlement, actually and reasonably incurred by him in
connection with the action, suit, or proceeding, if he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the Trust, and, with respect to any criminal action or proceeding, had no
reasonable cause to believe his conduct was unlawful. The termination of any
action, suit or proceeding by judgment, order, settlement, conviction, or upon a
plea of nolo contendere or its equivalent, shall not, of itself, create a
presumption that the person did not act in good faith and in a manner which he
reasonably believed to be in or not opposed to the best interests of the Trust,
and, with respect to any criminal action or proceeding, had reasonable cause to
believe that his conduct was unlawful.

     (b) The Trust shall indemnify any person who was or is a party or is
threatened to be made a party to any threatened, pending or completed action or
suit by or on behalf of the Trust to obtain a judgment or decree in its favor by
reason of the fact that he is or was a Trustee, officer, employee, or agent of
the Trust. The indemnification shall be against expenses, including attorneys'
fees actually and reasonably incurred by him in connection with the defense or
settlement of the action or suit, if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the Trust;
except that no indemnification shall be made in respect of any claim, issue, or
matter as to which the person has been adjudged to be liable for negligence or
misconduct in the performance of his duty to the Trust, except to the extent
that the court in which the action or suit was brought, or a court of equity in
the county in which the Trust has its principal office, determines upon
application that, despite the adjudication of liability but in view of all
circumstances of the case, the person is fairly and reasonably entitled to
indemnity for those expenses which the court shall deem proper, provided such
Trustee, officer, employee or agent is not adjudged to be liable by reason of
his willful misfeasance, bad faith, gross negligence or reckless disregard of
the duties involved in the conduct of his office.

     (c) To the extent that a Trustee, officer, employee, or agent of the Trust
has been successful on the merits or otherwise in defense of any action, suit or
proceeding referred to in subsection (a) or (b) or in defense of any claim,
issue or matter therein, he shall be indemnified against expenses, including
attorneys' fees, actually and reasonably incurred by him in connection
therewith.

     (d) (1) Unless a court orders otherwise, any indemnification under
subsections (a) or (b) of this section may be made by the Trust only as
authorized in the specific case after a determination that indemnification of
the Trustee, officer, employee, or agent is proper in the circumstances
because he has met the applicable standard of conduct set forth in subsections
(a) or (b).

                                        4
<PAGE>

         (2) The determination shall be made:

             (i) By the Trustees, by a majority vote of a quorum which consists
          of Trustees who were not parties to the action, suit or proceeding; or

            (ii) If the required quorum is not obtainable, or if a quorum of
          disinterested Trustees so directs, by independent legal counsel in a
          written opinion; or

           (iii) By the Shareholders.

         (3) Notwithstanding any provision of this Section 4.8, no person shall
         be entitled to indemnification for any liability, whether or not there
         is an adjudication of liability, arising by reason of willful
         misfeasance, bad faith, gross negligence, or reckless disregard of
         duties as described in Section 17(h) and (i) of the Investment Company
         Act of 1940 ("disabling conduct"). A person shall be deemed not liable
         by reason of disabling conduct if, either:

             (i) a final decision on the merits is made by a court or other body
          before whom the proceeding was brought that the person to be
          indemnified ("indemnitee") was not liable by reason of disabling
          conduct; or

            (ii) in the absence of such a decision, a reasonable determination,
          based upon a review of the facts, that the indemnitee was not liable
          by reason of disabling conduct, is made by either--

                (A) a majority of a quorum of Trustees who are neither
                "interested persons" of the Trust, as defined in Section
                2(a)(19) of the Investment Company Act of 1940, nor parties to
                the action, suit or proceeding, or

                (B) an independent legal counsel in a written opinion.

       (e)   Expenses, including attorneys' fees, incurred by a Trustee,
officer, employee or agent of the Trust in defending a civil or criminal action,
suit or proceeding may be paid by the Trust in advance of the final disposition
thereof if:

          (1) authorized in the specific case by the Trustees; and

          (2) the Trust receives an undertaking by or on behalf of the Trustee,
      officer, employee or agent of the Trust to repay the advance if it is not
      ultimately determined that such person is entitled to be indemnified by
      the Trust; and

          (3) either, (i) such person provides a security for his undertaking,
      or

             (ii) the Trust is insured against losses by reason of any lawful
           advances, or

            (iii) a determination, based on a review of readily available
           facts, that there is reason to believe that such person ultimately
           will be found entitled to indemnification, is made by either--

                (A) a majority of a quorum which consists of Trustees who are
               neither "interested persons" of the Trust, as defined in Section
               2(a)(19) of the 1940 Act, nor parties to the action, suit or
               proceeding, or

                (B) an independent legal counsel in a written opinion.

     (f) The indemnification provided by this Section shall not be deemed
exclusive of any other rights to which a person may be entitled under any
by-law, agreement, vote of Shareholders or disinterested Trustees or otherwise,
both as to action in his official capacity and as to action in another capacity
while holding the office, and shall continue as to a person who has ceased to be
a Trustee, officer, employee, or agent and inure to the benefit of the heirs,
executors and administrators of such person; provided that no person may satisfy
any right of indemnity or reimbursement granted herein or to which he may be
otherwise entitled except out of the property of the Trust, and no Shareholder
shall be personally liable with respect to any claim for indemnity or
reimbursement or otherwise.

                                        5
<PAGE>

     (g) The Trust may purchase and maintain insurance on behalf of any person
who is or was a Trustee, officer, employee, or agent of the Trust, against any
liability asserted against him and incurred by him in any such capacity, or
arising out of his status as such. However, in no event will the Trust purchase
insurance to indemnify any officer or Trustee against liability for any act for
which the Trust itself is not permitted to indemnify him.

     (h) Nothing contained in this Section shall be construed to protect any
Trustee or officer of the Trust against any liability to the Trust or to its
security holders to which he would otherwise be subject by reason of willful
misfeasance, bad faith, gross negligence or reckless disregard of the duties
involved in the conduct of his office.

                                   ARTICLE V

                                   COMMITTEES

     SECTION 5.1. EXECUTIVE AND OTHER COMMITTEES. The Trustees, by resolution
adopted by a majority of the Trustees, may designate an Executive Committee
and/or committees, each committee to consist of two (2) or more of the Trustees
of the Trust and may delegate to such committees, in the intervals between
meetings of the Trustees, any or all of the powers of the Trustees in the
management of the business and affairs of the Trust. In the absence of any
member of any such committee, the members thereof present at any meeting,
whether or not they constitute a quorum, may appoint a Trustee to act in place
of such absent member. Each such committee shall keep a record of its
proceedings.

     The Executive Committee and any other committee shall fix its own rules or
procedure, but the presence of at least fifty percent (50%) of the members of
the whole committee shall in each case be necessary to constitute a quorum of
the committee and the affirmative vote of the majority of the members of the
committee present at the meeting shall be necessary to take action.

     All actions of the Executive Committee shall be reported to the Trustees at
the meeting thereof next succeeding to the taking of such action.

     SECTION 5.2. ADVISORY COMMITTEE. The Trustees may appoint an advisory
committee which shall be composed of persons who do not serve the Trust in any
other capacity and which shall have advisory functions with respect to the
investments of the Trust but which shall have no power to determine that any
security or other investment shall be purchased, sold or otherwise disposed of
by the Trust. The number of persons constituting any such advisory committee
shall be determined from time to time by the Trustees. The members of any such
advisory committee may receive compensation for their services and may be
allowed such fees and expenses for the attendance at meetings as the Trustees
may from time to time determine to be appropriate.

     SECTION 5.3. COMMITTEE ACTION WITHOUT MEETING. The provisions of these
By-Laws covering notices and meetings to the contrary notwithstanding, and
except as required by law, any action required or permitted to be taken at any
meeting of any Committee of the Trustees appointed pursuant to Section 5.1 of
these By-Laws may be taken without a meeting if a consent in writing setting
forth the action shall be signed by all members of the Committee entitled to
vote upon the action and such written consent is filed with the records of the
proceedings of the Committee.

                                   ARTICLE VI

                                    OFFICERS

     SECTION 6.1. EXECUTIVE OFFICERS. The executive officers of the Trust shall
be a Chairman of the Board, a President, one or more Vice Presidents, a
Secretary and a Treasurer. The Chairman of the Board shall be selected from
among the Trustees but none of the other executive officers need be a member of
the Board of Trustees. Two or more offices, except those of President and any
Vice President, may be held by the same person, but no officer shall execute,
acknowledge or verify any instrument in more than one capacity. The executive
officers of the Trust shall be elected annually by the Board of Trustees and
each executive officer so elected shall hold office until his successor is
elected and has qualified.

                                        6
<PAGE>

     SECTION 6.2. OTHER OFFICERS AND AGENTS. The Board of Trustees may also
elect one or more Assistant Vice Presidents, Assistant Secretaries and Assistant
Treasurers and may elect, or may delegate to the President the power to appoint,
such other officers and agents as the Board of Trustees shall at any time or
from time to time deem advisable.

     SECTION 6.3. TERM AND REMOVAL AND VACANCIES. Each officer of the Trust
shall hold office until his successor is elected and has qualified. Any officer
or agent of the Trust may be removed by the Trustees whenever, in its judgment,
the best interests of the Trust will be served thereby, but such removal shall
be without prejudice to the contractual rights, if any, of the person so
removed.

     SECTION 6.4. COMPENSATION OF OFFICERS. The compensation of officers and
agents of the Trust shall be fixed by the Board of Trustees, or by the President
to the extent provided by the Board of Trustees with respect to officers
appointed by the President.

     SECTION 6.5. POWER AND DUTIES. All officers and agents of the Trust, as
between themselves and the Trust, shall have such authority and perform such
duties in the management of the Trust as may be provided in or pursuant to these
By-Laws, or to the extent not so provided, as may be prescribed by the Board of
Trustees; provided, that no rights of any third party shall be affected or
impaired by any such By-Law or resolution of the Trustees unless he has
knowledge thereof.

     SECTION 6.6. THE CHAIRMAN OF THE BOARD. The Chairman of the Board shall
preside at all meetings of the shareholders and of the Board of Trustees, shall
be a signatory on all Annual and Semi-Annual Reports as may be sent to
shareholders, and he shall perform such other duties as the Board of Trustees
may from time to time prescribe.

     SECTION 6.7. THE PRESIDENT.  (a) The President shall be the chief executive
officer of the Trust; he shall have general and active management of the
business of the Trust, shall see that all orders and resolutions of the Board of
Trustees are carried into effect, and, in connection therewith, shall be
authorized to delegate to one or more Vice Presidents such of his powers and
duties at such times and in such manner as he may deem advisable.

     (b) In the absence of the Chairman, the President shall preside at all
meetings of the shareholders and the Board of Trustees; and he shall perform
such other duties as the Board of Trustees may from time to time prescribe.

     SECTION 6.8. THE VICE PRESIDENTS. The Vice Presidents shall be of such
number and shall have such titles as may be determined from time to time by the
Board of Trustees. The Vice President, or, if there be more than one, the Vice
Presidents in the order of their seniority as may be determined from time to
time by the Trustees or the President, shall, in the absence or disability of
the President, exercise the powers and perform the duties of the President, and
he or they shall perform such other duties as the Board of Trustees or the
President may from time to time prescribe.

     SECTION 6.9. THE ASSISTANT VICE PRESIDENTS. The Assistant Vice President,
or, if there be more than one, the Assistant Vice Presidents, shall perform such
duties and have such powers as may be assigned them from time to time by the
Board of Trustees or the President.

     SECTION 6.10. THE SECRETARY. The Secretary shall attend all meetings of the
Board of Trustees and all meetings of the Shareholders and record all the
proceedings of the meetings of the Shareholders and of the Board of Trustees in
a book to be kept for that purpose, and shall perform like duties for the
standing committees when required. He shall give, or cause to be given, notice
of all meetings of the Shareholders and special meetings of the Board of
Trustees, and shall perform such other duties and have such powers as the Board
of Trustees, or the President, may from time to time prescribe. He shall keep in
safe custody the seal of the Trust and affix or cause the same to be affixed to
any instrument requiring it, and, when so affixed, it shall be attested by his
signature or by the signature of an Assistant Secretary.

     SECTION 6.11. THE ASSISTANT SECRETARIES. The Assistant Secretary, or, if
there be more than one, the Assistant Secretaries in the order determined by the
Board of Trustees or the President, shall, in the absence or disability of the
Secretary, perform the duties and exercise the powers of the Secretary and shall
perform such duties and have such other powers as the Board of Trustees or the
President may from time to time prescribe.

                                        7
<PAGE>

     SECTION 6.12. THE TREASURER. The Treasurer shall be the chief financial
officer of the Trust. He shall keep or cause to be kept full and accurate
accounts of receipts and disbursements in books belonging to the Trust, and he
shall render to the Board of Trustees and the President, whenever any of them
require it, an account of his transactions as Treasurer and of the financial
condition of the Trust; and he shall perform such other duties as the Board of
Trustees, or the President, may from time to time prescribe.

     SECTION 6.13. THE ASSISTANT TREASURERS. The Assistant Treasurer, or, if
there shall be more than one, the Assistant Treasurers in the order determined
by the Board of Trustees or the President, shall, in the absence or disability
of the Treasurer, perform the duties and exercise the powers of the Treasurer
and shall perform such other duties and have such other powers as the Trustees,
or the President, may from time to time prescribe.

     SECTION 6.14. DELEGATION OF DUTIES. Whenever an officer is absent or
disabled, or whenever for any reason the Board of Trustees may deem it
desirable, the Board may delegate the powers and duties of an officer or officer
to any other officer or officers or to any Trustee or Trustees.

                                  ARTICLE VII

                          DIVIDENDS AND DISTRIBUTIONS

     Subject to any applicable provisions of law and the Declaration, dividends
and distributions upon the Shares may be declared at such intervals as the
Trustees may determine, in cash, in securities or other property, or in Shares,
from any sources permitted by law, all as the Trustees shall from time to time
determine.

     Inasmuch as the computation of net income and net profits from the sales of
securities or other properties for federal income tax purposes may vary from the
computation thereof on the records of the Trust, the Trustees shall have power,
in their discretion, to distribute as income dividends and as capital gain
distributions, respectively, amounts sufficient to enable the Trust to avoid or
reduce liability for federal income taxes.

                                  ARTICLE VIII

                             CERTIFICATES OF SHARES

     SECTION 8.1. CERTIFICATES OF SHARES. Certificates for Shares of each series
or class of Shares shall be in such form and of such design as the Trustees
shall approve, subject to the right of the Trustees to change such form and
design at any time or from time to time, and shall be entered in the records of
the Trust as they are issued. Each such certificate shall bear a distinguishing
number; shall exhibit the holder's name and certify the number of full Shares
owned by such holder; shall be signed by or in the name of the Trust by the
President, or a Vice President, and countersigned by the Secretary or an
Assistant Secretary or the Treasurer and an Assistant Treasurer of the Trust;
shall be sealed with the seal; and shall contain such recitals as may be
required by law. Where any certificate is signed by a Transfer Agent or by a
Registrar, the signature of such officers and the seal may be facsimile, printed
or engraved. The Trust may, at its option, determine not to issue a certificate
or certificates to evidence Shares owned of record by any Shareholder.

     In case any officer or officers who shall have signed, or whose facsimile
signature or signatures shall appear on, any such certificate or certificates
shall cease to be such officer or officers of the Trust, whether because of
death, resignation or otherwise, before such certificate or certificates shall
have been delivered by the Trust, such certificate or certificates shall,
nevertheless, be adopted by the Trust and be issued and delivered as though the
person or persons who signed such certificate or certificates or whose facsimile
signature or signatures shall appear therein had not ceased to be such officer
or officers of the Trust.

     No certificate shall be issued for any share until such share is fully
paid.

     SECTION 8.2. LOST, STOLEN, DESTROYED AND MUTILATED CERTIFICATES. The
Trustees may direct a new certificate or certificates to be issued in place of
any certificate or certificates theretofore issued by the Trust alleged to have
been lost, stolen or destroyed, upon satisfactory proof of such loss, theft, or

                                        8
<PAGE>

destruction; and the Trustees may, in their discretion, require the owner of
the lost, stolen or destroyed certificate, or his legal representative, to give
to the Trust and to such Registrar, Transfer Agent and/or Transfer Clerk as may
be authorized or required to countersign such new certificate or certificates, a
bond in such sum and of such type as they may direct, and with such surety or
sureties, as they may direct, as indemnity against any claim that may be against
them or any of them on account of or in connection with the alleged loss, theft
or destruction of any such certificate.

                                   ARTICLE IX

                                   CUSTODIAN

     SECTION 9.1. APPOINTMENT AND DUTIES. The Trust shall at times employ a
bank or trust company having capital, surplus and undivided profits of at least
five million dollars ($5,000,000) as custodian with authority as its agent, but
subject to such restrictions, limitations and other requirements, if any, as may
be contained in these By-Laws and the 1940 Act:

       (1) to receive and hold the securities owned by the Trust and deliver
      the same upon written or electronically transmitted order;

       (2) to receive and receipt for any moneys due to the Trust and deposit
      the same in its own banking department or elsewhere as the Trustees may
      direct;

       (3) to disburse such funds upon orders or vouchers;

all upon such basis of compensation as may be agreed upon between the Trustees
and the custodian. If so directed by a Majority Shareholder Vote, the custodian
shall deliver and pay over all property of the Trust held by it as specified in
such vote.

     The Trustees may also authorize the custodian to employ one or more
sub-custodians from time to time to perform such of the acts and services of the
custodian and upon such terms and conditions as may be agreed upon between the
custodian and such sub-custodian and approved by the Trustees provided that in
every case such sub-custodian shall be a bank or trust company organized under
the laws of the United States or one of the states thereof and having capital,
surplus and undivided profits of at least five million dollars ($5,000,000).

     SECTION 9.2. CENTRAL CERTIFICATE SYSTEM. Subject to such rules, regulations
and orders as the Commission may adopt, the Trustees may direct the custodian to
deposit all or any part of the securities owned by the Trust in a system for the
central handling of securities established by a national securities exchange or
a national securities association registered with the Commission under the
Securities Exchange Act of 1934, or such other person as may be permitted by the
Commission, or otherwise in accordance with the 1940 Act, pursuant to which
system all securities of any particular class or series of any issuer deposited
within the system are treated as fungible and may be transferred or pledged by
bookkeeping entry without physical delivery of such securities, provided that
all such deposits shall be subject to withdrawal only upon the order of the
Trust.

                                   ARTICLE X

                                WAIVER OF NOTICE

     Whenever any notice of the time, place or purpose of any meeting of
Shareholders, Trustees, or of any committee is required to be given in
accordance with law or under the provisions of the Declaration or these By-Laws,
a waiver thereof in writing, signed by the person or persons entitled to such
notice and filed with the records of the meeting, whether before or after the
holding thereof, or actual attendance at the meeting of shareholders, Trustees
or committee, as the case may be, in person, shall be deemed equivalent to the
giving of such notice to such person.

                                   ARTICLE XI

                                 MISCELLANEOUS

     SECTION 11.1. LOCATION OF BOOKS AND RECORDS. The books and records of the
Trust may be kept outside the Commonwealth of Massachusetts at such place or
places as the Trustees may from time to time determine, except as otherwise
required by law.

                                        9
<PAGE>

     SECTION 11.2. RECORD DATE. The Trustees may fix in advance a date as the
record date for the purpose of determining the Shareholders entitled to (i)
receive notice of, or to vote at, any meeting of Shareholders, or (ii) receive
payment of any dividend or the allotment of any rights, or in order to make a
determination of Shareholders for any other proper purpose. The record date, in
any case, shall not be more than one hundred eighty (180) days, and in the case
of a meeting of Shareholders not less than ten (10) days, prior to the date on
which such meeting is to be held or the date on which such other particular
action requiring determination of Shareholders is to be taken, as the case may
be. In the case of a meeting of Shareholders, the meeting date set forth in the
notice to Shareholders accompanying the proxy statement shall be the date used
for purposes of calculating the 180 day or 10 day period, and any adjourned
meeting may be reconvened without a change in record date. In lieu of fixing a
record date, the Trustees may provide that the transfer books shall be closed
for a stated period but not to exceed, in any case, twenty (20) days. If the
transfer books are closed for the purpose of determining Shareholders entitled
to notice of a vote at a meeting of Shareholders, such books shall be closed for
at least ten (10) days immediately preceding the meeting.

     SECTION 11.3. SEAL. The Trustees shall adopt a seal, which shall be in such
form and shall have such inscription thereon as the Trustees may from time to
time provide. The seal of the Trust may be affixed to any document, and the seal
and its attestation may be lithographed, engraved or otherwise printed on any
document with the same force and effect as if it had been imprinted and attested
manually in the same manner and with the same effect as if done by a
Massachusetts business corporation under Massachusetts law.

     SECTION 11.4. FISCAL YEAR. The fiscal year of the Trust shall end on such
date as the Trustees may by resolution specify, and the Trustees may by
resolution change such date for future fiscal years at any time and from time to
time.

     SECTION 11.5. ORDERS FOR PAYMENT OF MONEY. All orders or instructions for
the payment of money of the Trust, and all notes or other evidences of
indebtedness issued in the name of the Trust, shall be signed by such officer or
officers or such other person or persons as the Trustees may from time to time
designate, or as may be specified in or pursuant to the agreement between the
Trust and the bank or trust company appointed as Custodian of the securities and
funds of the Trust.

                                  ARTICLE XII

                      COMPLIANCE WITH FEDERAL REGULATIONS

     The Trustees are hereby empowered to take such action as they may deem to
be necessary, desirable or appropriate so that the Trust is or shall be in
compliance with any federal or state statute, rule or regulation with which
compliance by the Trust is required.

                                  ARTICLE XIII

                                   AMENDMENTS

     These By-Laws may be amended, altered, or repealed, or new By-Laws may be
adopted, (a) by a Majority Shareholder Vote, or (b) by the Trustees; provided,
however, that no By-Law may be amended, adopted or repealed by the Trustees if
such amendment, adoption or repeal requires, pursuant to law, the Declaration,
or these By-Laws, a vote of the Shareholders. The Trustees shall in no event
adopt By-Laws which are in conflict with the Declaration, and any apparent
inconsistency shall be construed in favor of the related provisions in the
Declaration.

                                  ARTICLE XIV

                              DECLARATION OF TRUST

     The Declaration of Trust establishing Morgan Stanley Dean Witter U.S.
Government Money Market Trust, dated November 18, 1981, a copy of which,
together with all amendments thereto, is on file in the office of the Secretary
of the Commonwealth of Massachusetts, provides that the name Morgan
Stanley

                                        10
<PAGE>

Dean Witter U.S. Government Money Market Trust refers to the Trustees under the
Declaration collectively as Trustees, but not as individuals or personally; and
no Trustee, Shareholder, officer, employee or agent of Morgan Stanley Dean
Witter U.S. Government Money Market Trust shall be held to any personal
liability, nor shall resort be had to their private property for the
satisfaction of any obligation or claim or otherwise, in connection with the
affairs of said Morgan Stanley Dean Witter U.S. Government Money Market Trust,
but the Trust Estate only shall be liable.

                                        11


<PAGE>
                          SECOND AMENDED AND RESTATED
                              RETIREMENT PLAN FOR
                            NON-INTERESTED TRUSTEES
                                  OR DIRECTORS
 
    Certain of the investment companies for which Morgan Stanley Dean Witter
Advisors Inc. ("MSDW Advisors") currently acts as manager or adviser adopted a
Retirement Plan for Non-Interested Trustees and Directors (the "Original Plan")
on February 21, 1991 (the "Commencement Date"). The Original Plan was amended
and restated on October 22, 1993, effective January 1, 1994 and further amended
by First Amendment dated December 19, 1995 and by Second Amendment dated May 8,
1997. The participating Funds now desire to amend and restate the Plan further
as provided herein effective as of the Commencement Date (as so amended, the
"Plan"), for the purposes of expanding the flexibility of Non-Interested
Trustees and Directors to make and change their elections of benefits.
 
    1.  DEFINITIONS
 
    (a) "Independent Board Member" shall mean (i) a Trustee of an Adopting Fund
if the Adopting Fund is organized as a Massachusetts business trust, (ii) a
Director of an Adopting Fund if the Adopting Fund is organized as a corporation,
and (iii) a "director" (as such term is defined in Section 2(a)(12) of the
Investment Company Act of 1940, as amended [the "Act"]) of an Adopting Fund if
the Adopting Fund is any other type of organization, who in any such case is not
an interested person (as such term is defined in Section 2(a)(19) of the Act) of
MSDW Advisors.
 
    (b) "Eligible Board Member" shall mean an Independent Board Member who at
the time of Retirement (as hereinafter defined) has served as an Independent
Board Member of any Adopting Fund for at least five years, or such lesser period
as may be determined by the Board.
 
    (c) "Eligible Service" shall mean service as an Independent Board Member.
 
    (d) "Eligible Retirement Date" shall mean, with respect to any Independent
Board Member, the later of (i) January 1, 1993, (ii) the first day of the
calendar month following the month in which such Independent Board Member's
seventy-second birthday occurs, or (iii) such later date as the Board may
establish as his or her "Eligible Retirement Date."
 
    (e) "Retirement" shall mean any termination of service of an Independent
Board Member except any termination which the Board determines to have resulted
from the Independent Board Member's willful misfeasance, bad faith, gross
negligence or reckless disregard of the duties involved in the conduct of the
office of Independent Board Member.
 
    (f) "Benefit" shall mean with respect to any Eligible Board Member, (i) the
Regular Benefit, unless the Alternate Benefit has been elected or the Early
Benefit granted, (ii) the Alternate Benefit, if elected by such Eligible Board
Member, unless the Early Benefit has been granted, or (iii) the Early Benefit,
if granted by the Board.
 
    (g) "Eligible Compensation" shall mean, with respect to any Eligible Board
Member of any Adopting Fund, an amount equal to one-fifth of the total
compensation, inclusive of compensation as a member of the Board or of a Board
Committee or as chairperson of a Board Committee, earned by such Eligible Board
Member for Eligible Service with respect to such Adopting Fund (other than under
this Plan) in the five year period prior to the date of his or her Retirement.
 
    (h) "Actuarial Equivalent" shall mean an actuarially equivalent benefit, as
computed by the Board with the advice of an enrolled actuary (as defined in the
Employee Retirement Income Security Act of 1974, as amended ["ERISA"]), using
assumptions determined by the Board at the time of the computation.
 
    (i) "Board" shall mean, with respect to any Adopting Fund, the Board of
Directors or Trustee or "directors," (as such term is defined in Section
2(a)(12) of the Act, of such Adopting Fund.
 
    (j) "Adoption Date" shall mean February 21, 1991.
 
                                       1
<PAGE>
    2.  ELIGIBILITY
 
    Each Eligible Board Member will be eligible to receive a Benefit from each
Adopting Fund commencing on such Eligible Board Member's Eligible Retirement
Date.
 
    3.  RETIREMENT DATE; AMOUNT OF BENEFIT
 
    (a) RETIREMENT. Each Independent Board Member will retire not later than his
or her Eligible Retirement Date. The foregoing provision shall be deemed by the
adoption of this Plan by any Fund to be an amendment of such Fund's by-laws
superseding any provision therein that an Independent Board Member shall serve
until his or her successor shall have been elected and qualified.
Notwithstanding the foregoing, the Board of any Adopting Fund may, to avoid the
simultaneous retirement of more than one of the Independent Board Members or for
any other appropriate reason, waive the obligation of any Independent Board
Member to retire on such date and may establish a later date as his or her
"Eligible Retirement Date." Any establishment of an Eligible Retirement Date may
be further extended by the Board.
 
    (b) REGULAR RETIREMENT BENEFIT. Upon Retirement, each Eligible Board Member
will receive, commencing as of such Eligible Board Member's Eligible Retirement
Date and continuing for the remainder of the Eligible Board Member's life, from
each Adopting Fund a retirement benefit (the "Regular Benefit") paid at an
annual rate equal to the percentage of his or her Eligible Compensation
established by resolution of the Board of such Adopting Fund most recently
adopted prior to the date of his or her retirement (the "Most Recent
Resolution") as the "Minimum Percentage," plus an additional percentage of such
Eligible Compensation for each full month of Eligible Service for any of the
Adopting Funds in excess of five years established by the Most Recent Resolution
as the "Monthly Additional Percentage," up to the percentage established by the
Most Recent Resolution as the "Maximum Percentage" of such Eligible Compensation
for ten or more years of Eligible Service for any of the Adopting Funds.
 
    (c) ELECTION OF ALTERNATE PAYMENT OF BENEFIT. Each Independent Board Member
shall have the option, exercisable at any time, and revisable at any time and
from time to time, prior to his or her first acceptance of benefits under the
Plan to elect (i) to receive, subject to being or becoming an Eligible Board
Member, a retirement benefit (the "Alternate Benefit") based upon the combined
life expectancy of such Eligible Board Member and his or her spouse on the date
of such Eligible Board Member's Retirement (rather than solely upon such
Eligible Board Member's own life, as shall be the case unless such Eligible
Board Member shall otherwise elect as provided in this Section 3(c)), and (ii)
if the Independent Board Member elects to receive the Alternate Benefit, to
elect a benefit either (x) to the last survivor of the Eligible Board Member or
spouse, whether the Eligible Board Member or spouse is the last survivor (a
"joint and last survivor" benefit) or (y) to the Eligible Board Member's spouse
if the spouse survives the Eligible Board Member (a "joint and contingent
survivor" benefit) equal in periodic amount to a percentage (the "Designated
Survivor's Percentage") of the periodic amount that would be, or would be
assumed to be, in effect while both the Eligible Board Member and spouse were
alive. The Designated Survivor's Percentage shall be the percentage stated in
the most recently delivered notice of election given by such Independent Board
Member, or, if no percentage is stated in any such notice, 100%. Payment of the
Alternate Benefit shall commence on the later of such Eligible Board Member's
Eligible Retirement Date or the date of his or her Retirement, shall be reduced
to the Designated Survivor's Percentage (if less than 100%) upon the earlier of
the deceases of the Eligible Board Member and spouse in the case of a joint and
last survivor benefit, or of the Eligible Board Member in the case of a joint
and contingent survivor benefit, and shall be payable through the remainder of
the life of the survivor of such Eligible Board Member and spouse. The Alternate
Benefit shall be the Actuarial Equivalent of the Regular Benefit provided under
paragraph 3(b). In the event of the death of an Eligible Board Member who has
chosen the Alternate Benefit prior to such Eligible Board Member's Retirement,
his or her spouse shall be entitled to a retirement benefit, commencing upon
such death, which shall be the Actuarial Equivalent of the benefit such spouse
would have received had such Eligible Board Member died on his or her Eligible
Retirement Date.
 
    (d) EARLY PAYMENT OF BENEFIT. An Eligible Board Member for good cause may
apply to the Board of any Adopting Fund for, and, at the discretion of such
Board, may be granted, a retirement benefit (the "Early Benefit") which is the
Actuarial Equivalent of the Regular Benefit or Alternate Benefit previously
elected
 
                                       2
<PAGE>
by such Eligible Board Member. Payment of the Early Benefit shall commence on a
date fixed by the Board in its sole discretion as such Eligible Board Member's
Eligible Retirement Date and shall be payable through the remainder of such
Eligible Board Member's life, or, if the Alternate Benefit had been elected, the
later of the lives of such Eligible Board Member and spouse. Good cause for
these purposes may include (but is not limited to) the permanent disability of
the Eligible Board Member.
 
    (e) Anything contained herein to the contrary notwithstanding, upon the
adoption by an Adopting Fund of a plan of liquidation, such Adopting Fund shall
pay to each Eligible Board Member who has retired, in lieu of his or her Benefit
from such Adopting Fund, an amount (the "Lump Sum") equal to the then present
value of the Benefit, using a discount rate determined by the Board at the time
of the computation. The Lump Sum shall be paid by such Adopting Fund at or
before the final liquidation and dissolution of such Adopting Fund.
 
    4.  TIME OF PAYMENT
 
    The Benefit to each Eligible Board Member or his or her spouse will, except
as provided in Section 3(c), 3(d) or 3(e) hereof, commence on such Eligible
Board Member's Eligible Retirement Date and will be paid each year in quarterly
installments that are as nearly equal as possible on the first day of each
calendar quarter.
 
    5.  PAYMENT OF BENEFIT; ALLOCATION OF COSTS
 
    Each Adopting Fund is responsible for the payment of Benefits based upon
Eligible Compensation from such Adopting Fund, as well as its proportionate
share of all expenses of administration of the Plan, including without
limitation all accounting and legal fees and expenses and fees and expenses of
any enrolled actuary. The obligations of each Adopting Fund to pay such benefits
and expenses will not be secured or funded in any manner, and such obligations
will not have any preference over the lawful claims of the Adopting Funds'
creditors and stockholders, shareholders, beneficiaries or limited partners, as
the case may be. To the extent that an Adopting Fund consists of one or more
separate portfolios, such costs and expenses will be allocated among such
portfolios in the proportion that compensation of Independent Board Members is
allocated among such portfolios.
 
    6.  ADMINISTRATION
 
    (a) ADMINISTRATION. Any question involving entitlement to payments under or
the administration of the Plan will be referred to the Board, which shall make
all interpretations and determinations necessary or desirable for the Plan's
administration (such interpretations and determinations to be final and
conclusive) and shall cause such records to be kept as may be necessary for the
administration of the Plan.
 
    7.  MISCELLANEOUS
 
    (a) RIGHTS NOT ASSIGNABLE. The right to receive any payment under the Plan
is not transferable or assignable. Except as otherwise provided herein with
respect to the Alternate Benefit, the Plan shall not create any benefit, cause
of action, right of sale, transfer, assignment, pledge, encumbrance, or other
such right in any spouse or heirs or the estate of any Eligible Board Member or
retired Eligible Board Member.
 
    (b) AMENDMENT, ETC. With respect to each Adopting Fund, the Board, including
a majority of the Independent Board Members of such Board, may at any time amend
or terminate the Plan or waive any provision of the Plan, PROVIDED, that except
as otherwise provided herein, no amendment, termination or waiver will impair
the rights of an Independent Board Member to receive upon Retirement the
payments which would have been made to such Independent Board Member had there
been no such amendment, termination or waiver (based upon such Board Member's
Eligible Service to the date of such amendment, termination or waiver) or the
rights of a retired Eligible Board Member to receive any Benefit due under the
Plan, without the consent of such Independent Board Member or Eligible Board
Member. Notwithstanding any provision to the contrary, the Board, with the
concurrence of a majority of the Independent Board Members of such Board and
without the consent of any individual Independent Board Member, may at any time
(i) amend or terminate the Plan to comply with any applicable provision of law
or any rule or regulation adopted, or proposed to be adopted, by any
governmental agency or any decision of any court or administrative agency, (ii)
change any assumptions used to determine what benefit may be an
 
                                       3
<PAGE>
Actuarial Equivalent, or (iii) terminate the Plan of an Adopting Fund (an
"Acquired Adopting Fund") substantially all the assets of which are acquired by
an entity which is itself an Adopting Fund (the "Acquiring Adopting Fund")
pursuant to a plan of reorganization between the Acquired Adopting Fund and the
Acquiring Adopting Fund (the "Reorganization Plan"), such termination to be
deemed approved upon adoption of the Reorganization Plan and to be effective
upon the effectiveness of the reorganization contemplated thereby without
liability or further obligation for any benefits accrued or otherwise payable to
an Independent Board Member by the Acquired Adopting Fund.
 
    (c) NO RIGHT TO REELECTION. Nothing in the Plan will create any obligation
on the part of the Board to nominate any Independent Board Member for
reelection.
 
    (d) VACANCIES. Although the Board will retain the right to increase or
decrease its size, it shall be the general policy to replace each retired
Independent Board Member by selecting a new Independent Board Member from
candidates recommended by the remaining Independent Board Members.
 
    (e) CONSULTING. Each retired Eligible Board Member may render such services
for any of the Adopting Funds, for such compensation, as may be agreed upon from
time to time by such retired Eligible Board Member and the Board.
 
    (f) EFFECTIVENESS. The Plan will be effective for all Independent Board
Members who have dates of Retirement occurring on or after the Adoption Date.
Periods of Eligible Service shall include periods commencing prior to such date.
 
                                       4
<PAGE>
                       MORGAN STANLEY DEAN WITTER FUNDS:
                  FUNDS THAT HAVE ADOPTED THE RETIREMENT PLAN
                    FOR NON-INTERESTED TRUSTEES OR DIRECTORS
                                   SCHEDULE A
                                   MARCH 1999
 
<TABLE>
<S>        <C>
1)         Active Assets California Tax-Free Trust
2)         Active Assets Government Securities Trust
3)         Active Assets Money Trust
4)         Active Assets Tax-Free Trust
5)         Morgan Stanley Dean Witter American Value Fund
6)         Morgan Stanley Dean Witter California Insured Municipal Income Trust
7)         Morgan Stanley Dean Witter California Quality Municipal Securities
8)         Morgan Stanley Dean Witter California Tax-Free Daily Income Trust
9)         Morgan Stanley Dean Witter California Tax-Free Income Fund
10)        Morgan Stanley Dean Witter Capital Growth Securities
11)        Morgan Stanley Dean Witter Convertible Securities Trust
12)        Morgan Stanley Dean Witter Developing Growth Securities Trust
13)        Morgan Stanley Dean Witter Diversified Income Trust
14)        Morgan Stanley Dean Witter Dividend Growth Securities Inc.
15)        Morgan Stanley Dean Witter European Growth Fund Inc.
16)        Morgan Stanley Dean Witter Federal Securities Trust
17)        Morgan Stanley Dean Witter Global Dividend Growth Securities
18)        Morgan Stanley Dean Witter Government Income Trust
19)        Morgan Stanley Dean Witter Health Sciences Trust
20)        Morgan Stanley Dean Witter High Income Advantage Trust
21)        Morgan Stanley Dean Witter High Income Advantage Trust II
22)        Morgan Stanley Dean Witter High Yield Securities Inc.
23)        Morgan Stanley Dean Witter Income Securities Inc.
24)        Morgan Stanley Dean Witter Insured Municipal Bond Trust
25)        Morgan Stanley Dean Witter Insured Municipal Income Trust
26)        Morgan Stanley Dean Witter Insured Municipal Securities
27)        Morgan Stanley Dean Witter Insured Municipal Trust
28)        Morgan Stanley Dean Witter Intermediate Income Securities
29)        Morgan Stanley Dean Witter Limited Term Municipal Trust
30)        Morgan Stanley Dean Witter Liquid Asset Fund Inc.
31)        Morgan Stanley Dean Witter Multi-State Municipal Series Trust
32)        Morgan Stanley Dean Witter Municipal Income Opportunities Trust
33)        Morgan Stanley Dean Witter Municipal Income Opportunities Trust II
34)        Morgan Stanley Dean Witter Municipal Income Opportunities Trust III
35)        Morgan Stanley Dean Witter Municipal Income Trust
36)        Morgan Stanley Dean Witter Municipal Income Trust II
37)        Morgan Stanley Dean Witter Municipal Premium Income Trust
38)        Morgan Stanley Dean Witter Natural Resource Development Securities Inc.
39)        Morgan Stanley Dean Witter New York Municipal Money Market Trust
40)        Morgan Stanley Dean Witter New York Tax-Free Income Fund
41)        Morgan Stanley Dean Witter Pacific Growth Fund Inc.
42)        Morgan Stanley Dean Witter Prime Income Trust
43)        Morgan Stanley Dean Witter Quality Municipal Income Trust
44)        Morgan Stanley Dean Witter Quality Municipal Investment Trust
45)        Morgan Stanley Dean Witter Quality Municipal Securities
46)        Morgan Stanley Dean Witter Short-Term U.S. Treasury Trust
47)        Morgan Stanley Dean Witter Strategist Fund
</TABLE>
 
                                       5
<PAGE>
<TABLE>
<S>        <C>
48)        Morgan Stanley Dean Witter Tax-Exempt Securities Trust
49)        Morgan Stanley Dean Witter Tax-Free Daily Income Trust
50)        Morgan Stanley Dean Witter U.S. Government Money Market Trust
51)        Morgan Stanley Dean Witter U.S. Government Securities Trust
52)        Morgan Stanley Dean Witter Utilities Fund
53)        Morgan Stanley Dean Witter Value-Added Market Series
54)        Morgan Stanley Dean Witter Variable Investment Series
55)        Morgan Stanley Dean Witter World Wide Income Trust
</TABLE>
 
                                       6

<PAGE>


CONSENT OF INDEPENDENT ACCOUNTANTS


We hereby consent to the use in the Statement of Additional Information 
constituting part of this Post-Effective Amendment No. 20 to the registration 
statement on Form N-1A (the "Registration Statement") of our report dated 
March 5,1999, relating to the financial statements and financial highlights 
of Morgan Stanley Dean Witter U.S. Government Money Market Trust, formerly 
Dean Witter U.S. Government Money Market Trust, which appears in such 
Statement of Additional Information, and to the incorporation by reference of 
our report into the Prospectus which constitutes part of this Registration 
Statement. We also consent to the references to us under the headings 
"Custodian and Independent Accountants" and "Experts" in such Statement of 
Additional Information and to the reference to us under the heading 
"Financial Highlights" in such Prospectus.


PricewaterhouseCoopers LLP
1177 Avenue of the Americas
New York, New York 10036
March 26, 1999








<TABLE> <S> <C>

<PAGE>
<ARTICLE> 6
<SERIES>
<NAME> MSDW U.S. GOVERNMENT MONEY MARKET
<NUMBER> 001
       
<S>                             <C>
<PERIOD-TYPE>                   YEAR
<FISCAL-YEAR-END>                          JAN-31-1999
<PERIOD-END>                               JAN-31-1999
<INVESTMENTS-AT-COST>                    1,024,316,284
<INVESTMENTS-AT-VALUE>                   1,024,316,284
<RECEIVABLES>                                  328,520
<ASSETS-OTHER>                                 126,227
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           1,024,771,031
<PAYABLE-FOR-SECURITIES>                   (6,555,859)
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    (750,409)
<TOTAL-LIABILITIES>                        (7,306,268)
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 1,017,463,124
<SHARES-COMMON-STOCK>                    1,017,463,124
<SHARES-COMMON-PRIOR>                      890,569,126
<ACCUMULATED-NII-CURRENT>                        1,639
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                              0
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                             0
<NET-ASSETS>                             1,017,464,763
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                           50,615,622
<OTHER-INCOME>                                       0
<EXPENSES-NET>                             (8,766,643)
<NET-INVESTMENT-INCOME>                     41,848,979
<REALIZED-GAINS-CURRENT>                        40,360
<APPREC-INCREASE-CURRENT>                            0
<NET-CHANGE-FROM-OPS>                       41,889,339
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                 (41,849,500)
<DISTRIBUTIONS-OF-GAINS>                      (40,360)
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                  2,239,344,299
<NUMBER-OF-SHARES-REDEEMED>            (2,155,004,652)
<SHARES-REINVESTED>                         41,717,140
<NET-CHANGE-IN-ASSETS>                     126,893,477
<ACCUMULATED-NII-PRIOR>                          2,160
<ACCUMULATED-GAINS-PRIOR>                            0
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                 (4,236,205)
<GROSS-ADVISORY-FEES>                                0
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                            (8,766,643)
<AVERAGE-NET-ASSETS>                       932,777,233
<PER-SHARE-NAV-BEGIN>                             1.00
<PER-SHARE-NII>                                  0.045
<PER-SHARE-GAIN-APPREC>                              0
<PER-SHARE-DIVIDEND>                           (0.045)
<PER-SHARE-DISTRIBUTIONS>                            0
<RETURNS-OF-CAPITAL>                                 0
<PER-SHARE-NAV-END>                               1.00
<EXPENSE-RATIO>                                   0.94
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                                 0
        

</TABLE>


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