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Filed Pursuant to Rule 497
Registration File No.: 33-46049
SUPPLEMENT TO THE STATEMENT OF ADDITIONAL INFORMATION
OF
TCW/DW NORTH AMERICAN GOVERNMENT INCOME TRUST DATED JANUARY 30, 1998
The Trustees of TCW/DW North American Government Income Trust have
approved certain changes to the Systematic Withdrawal Plan of that company, to
take effect on October 1, 1998. EFFECTIVE OCTOBER 1, 1998, the disclosure in
the section of the above Statement of Additional Information entitled
"SHAREHOLDER SERVICES - Systematic Withdrawal Plan" is hereby replaced by the
following:
Systematic Withdrawal Plan. As discussed in the Prospectus, a systematic
withdrawal plan (the "Withdrawal Plan") is available for shareholders whose
shares of TCW/DW Funds have an aggregate value of $10,000 or more. Shares
of any Fund from which redemptions will be made pursuant to the Plan must
have a value of $1,000 or more (referred to as a "SWP Fund"). The required
share values are determined on the date the shareholder establishes the
Withdrawal Plan. The Withdrawal Plan provides for monthly, quarterly,
semi-annual or annual payments in any amount not less than $25, or in any
whole percentage of the value of the SWP Funds' shares, on an annualized
basis. If the SWP Fund shares, including shares acquired in exchange for
shares of other Funds, are subject to a contingent deferred sales charge
("CDSC"), any applicable CDSC will be imposed on shares redeemed under the
Withdrawal Plan (see "Purchase of Fund Shares" in the Statements of
Additional Information of the Funds offered with a CDSC), except that the
CDSC, if any, will be waived on redemptions under the Withdrawal Plan of up
to 12% annually of the value of each SWP Fund account, based on the share
values next determined after the shareholder establishes the Withdrawal
Plan. (For shareholders who established the Withdrawal Plan prior to
October 1, 1998, the value of each SWP Fund account for the purpose of the
12% CDSC waiver will be determined at 4:00 p.m., New York time, on October
2, 1998.) Redemptions for which this CDSC waiver policy applies may be in
amounts up to 1% per month, 3% per quarter, 6% semi-annually or 12%
annually. Under this CDSC waiver policy, amounts withdrawn each period will
be paid by first redeeming shares not subject to a CDSC because the shares
were purchased by the reinvestment of dividends or capital gains
distributions, the CDSC period has elapsed or some other waiver of the CDSC
applies. If shares subject to a CDSC must be redeemed, shares held for the
longest period of time will be redeemed first and continuing with shares
held the next longest period of time until shares held the shortest period
of time are redeemed. Any shareholder participating in the Withdrawal Plan
will have sufficient shares redeemed from his or her account so that the
proceeds (net of any applicable CDSC) to the shareholder will be the
designated monthly, quarterly, semi-annual or annual amount.
A shareholder may suspend or terminate participation in the Withdrawal
Plan at any time. A shareholder who has suspended participation may resume
payments under the Withdrawal Plan, without requiring a new determination
of the account value for the 12% CDSC waiver. The Withdrawal Plan may be
terminated or revised at any time by the Fund.
Prior to adding an additional SWP Fund to an existing Withdrawal Plan,
the required $10,000/$1,000 share values must be met, to be calculated on
the date the shareholder adds the additional SWP Fund. However, the
addition of a new SWP Fund will not change the account value for the 12%
CDSC waiver for the SWP Funds already participating in the Withdrawal Plan.
Dividends and capital gains distributions on shares held under the
Systematic Withdrawal Plan will be invested in additional full and
fractional shares at net asset value (without a sales charge). Shares will
be credited to an open account for the investor by the Transfer Agent; no
share certificates will be issued. A shareholder is entitled to a share
certificate upon written request to the Transfer Agent, although in that
event the shareholder's Withdrawal Plan will be terminated.
The Transfer Agent acts as agent for the shareholder in tendering to the
Fund for redemption sufficient full and fractional shares to provide the
amount of the periodic withdrawal payment designated in the application.
The shares will be redeemed at their net asset value determined, at the
shareholder's option, on the tenth or twenty-fifth day (or next following
business day) of the relevant month, quarter, or semi-annual or annual
period and normally a check for the proceeds will be mailed
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by the Transfer Agent, or amounts credited to a shareholder's Dean Witter
Reynolds Inc. or other selected broker-dealer brokerage account, or amounts
deposited electronically into the shareholder's bank account via the
Automated Clearing House, within five business days after the date of
redemption.
Withdrawal Plan payments should not be considered as dividends, yields or
income. If periodic withdrawal plan payments continuously exceed net
investment income and net capital gains, the shareholder's original
investment will be correspondingly reduced and ultimately exhausted. Each
withdrawal constitutes a redemption of shares and any gain or loss realized
must be recognized for federal income tax purposes. Shareholders of the
Fund who acquired their shares other than by exchange may make additional
investments under the Withdrawal Plan subject only to the Fund's minimum
investment requirement.
Any shareholder who wishes to have payments under the Withdrawal Plan
made to a third party, or sent to an address other than the one listed on
the account, must send complete written instructions to the Transfer Agent
to enroll in the Withdrawal Plan. The shareholder's signature on such
instructions must be guaranteed by an eligible guarantor acceptable to the
Transfer Agent (shareholders should contact the Transfer Agent for a
determination as to whether a particular institution is such an eligible
guarantor). A shareholder may, at any time, change the amount and interval
of withdrawal payments and the address to which checks are mailed through
his or her Morgan Stanley Dean Witter Financial Advisor or other selected
broker-dealer representative or by written notification to the Transfer
Agent. In addition, the party and/or the address to which checks are mailed
may be changed by written notification to the Transfer Agent, with
signature guarantees required in the manner described above. The
shareholder may also terminate the Withdrawal Plan at any time by written
notice to the Transfer Agent. In the event of such termination, the account
will be continued as a regular Shareholder Investment Account. The
shareholder may also redeem all or part of the shares held in the
Withdrawal Plan account (see "Repurchases and Redemptions" in the
Prospectus) at any time. Shareholders wishing to enroll in the Withdrawal
Plan should contact their Morgan Stanley Dean Witter Financial Advisor or
other selected broker-dealer representative.
September 30, 1998
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