RBB FUND INC, 497, 1998-06-08

RBB FUND INC
497, 1998-06-08

Previous: TRAVELERS GROUP INC, 8-K, 1998-06-08

Next: TYCO INTERNATIONAL LTD /BER/, 424B5, 1998-06-08

BOSTON PARTNERS LARGE CAP VALUE FUND
(INSTITUTIONAL CLASS)
OF
THE RBB FUND, INC.

Boston Partners Large Cap Value Fund (the "Fund") is an investment
portfolio of The RBB Fund, Inc. ("RBB"), an open-end management investment
company. The shares of the Institutional Class ("Shares") offered by this
Prospectus represent interests in the Fund. The Fund is a diversified fund that
seeks long-term growth of capital, with current income as a secondary objective,
primarily through equity investments, such as common stocks and securities
convertible into common stocks. It seeks to achieve its objectives by investing
at least 65% of its total assets in a diversified portfolio consisting of equity
securities of issuers with a market capitalization of primarily $1 billion or
greater and identified by Boston Partners Asset Management, L.P. (the "Adviser")
as equity securities that possess value characteristics. The Adviser examines
various factors in determining the value characteristics of such issuers,
including, but not limited to, price to book value ratios and price to earnings
ratios. These value characteristics are examined in the context of the issuer's
operating and financial fundamentals such as return on equity, earnings growth
and cash flow.

This Prospectus contains information that a prospective investor needs to
know before investing. Please keep it for future reference. A Statement of
Additional Information, dated December 1, 1997, has been filed with the
Securities and Exchange Commission and is incorporated by reference in this
Prospectus. It may be obtained free of charge from the Fund by calling (888)
261-4073. The Prospectus and the Statement of Additional Information are
available for reference, along with other related materials, on the SEC Internet
Web Site (http://www.sec.gov).

SHARES OF THE FUND ARE NOT DEPOSITS OR OBLIGATIONS OF OR GUARANTEED OR ENDORSED
BY PNC BANK, NATIONAL ASSOCIATION OR ANY OTHER BANK AND SHARES ARE NOT FEDERALLY
INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION, THE FEDERAL RESERVE BOARD
OR ANY OTHER AGENCY. INVESTMENTS IN SHARES OF THE FUND INVOLVE INVESTMENT RISKS,
INCLUDING THE POSSIBLE LOSS OF PRINCIPAL.

- --------------------------------------------------------------------------------

THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE COMMISSION OR
ANY STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS
PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

- --------------------------------------------------------------------------------

PROSPECTUS December 1, 1997
(as revised May 29, 1998)

<PAGE>

INTRODUCTION
- --------------------------------------------------------------------------------

RBB is an open-end management company incorporated under the laws of the
State of Maryland currently operating or proposing to operate twenty-six
separate investment portfolios. The Shares offered by this Prospectus represent
interests in the Boston Partners Large Cap Value Fund. RBB was incorporated in
Maryland on February 29, 1988.

FEE TABLE

The following table illustrates annual operating expenses as a percentage
of average daily net assets incurred by Institutional Shares of the Fund (after
fee waivers and expense reimbursements) during the fiscal period ended August
31, 1997, restated to reflect the expenses that the Fund expects to incur during
the current fiscal year with respect to its Institutional Shares. An example
based on the summary is also shown.

ANNUAL FUND OPERATING EXPENSES (AS A PERCENTAGE OF AVERAGE NET
ASSETS)

Management Fees (after waivers)*.............................0.08%
12b-1 Fees...................................................0.00%
Other Expenses (after waivers and reimbursements)*...........0.92%
-----
Total Fund Operating Expenses (after waivers
and expense reimbursements)*........................1.00%
=====

* In the absence of fee waivers and expense reimbursements, Management Fees
would be 0.75%; Other Expenses would be 1.89%; and Total Fund Operating
Expenses would be 2.64%. Management Fees are based on average daily net
assets and are calculated daily and paid monthly.

EXAMPLE

An investor would pay the following expenses on a $1,000 investment in the
Fund, assuming (1) a 5% annual return and (2) redemption at the end of each time
period:

ONE THREE FIVE TEN
YEAR YEARS YEARS YEARS
---- ----- ----- -----
Boston Partners Large Cap Value Fund $10 $32 $55 $122

The Fee Table is designed to assist an investor in understanding the
various costs and expenses that an investor in the Fund will bear directly or
indirectly. (For more complete descriptions of the various costs and expenses,
see "Management" below.) The Fee Table reflects expense reimbursements and
voluntary waivers of Management Fees and Other Expenses for the Fund. However,
there can be no assurance that any future expense reimbursements and waivers of
Management Fees or Other Expenses will not vary from the figures reflected in
the Fee Table.

The Example in the Fee Table assumes that all dividends and distributions
are reinvested and that the amounts listed under "Annual Fund Operating
Expenses" remain the same in the years shown. THE EXAMPLE SHOULD NOT BE
CONSIDERED A REPRESENTATION OF PAST OR FUTURE EXPENSES AND ACTUAL EXPENSES MAY
BE GREATER OR LESS THAN THOSE SHOWN.

FINANCIAL HIGHLIGHTS

The "Financial Highlights" presented below set forth certain investment
results for shares of the Institutional Class of the Fund for the period
indicated. Shares of the Institutional Class were first issued on January 2,
1997. The financial data included in this table should be read in conjunction
with the financial statements and notes thereto and the unqualified report of
the independent accountants thereon, which are incorporated by reference into
the Statement of Additional Information. Further information about the
performance of the Institutional Class of the Fund is available in the Annual
Report to Shareholders. Both the Statement of Additional Information and the
Annual Report to Shareholders may be obtained from the Fund free of charge by
calling the telephone number on page 1 of the prospectus.

-2-
<PAGE>

BOSTON PARTNERS LARGE CAP VALUE FUND
(FOR AN INSTITUTIONAL SHARE OUTSTANDING THROUGHOUT EACH PERIOD)

For the Period
January 2, 1997*
through August 31,
1997
------------------
PER SHARE OPERATING PERFORMANCE** $ 10.00
------
NET ASSET VALUE, BEGINNING OF PERIOD

Net investment income (1)........... 0.05
Net realized and unrealized gain on
investments(2)...................... 2.41
-----
Net increase in net assets resulting
from operations..................... 2.46
-----

NET ASSET VALUE, END OF PERIOD...... $12.46
=====

Total investment return(3).......... 24.60%

RATIOS/SUPPLEMENTAL DATA $24,603
Net assets, end of period (000).....

Ratio of expenses to average net
assets***(1)(4)................... 1.00%
Ratio of net investment income to
average net assets***(1).......... 1.19%
PORTFOLIO TURNOVER RATE****......... 67.16%
Average commission rate per share(5) $0.0397

- ----------------------

* Commencement of operations
** Calculated based on shares outstanding on the first and last day of
the period, except for dividends and distributions, if any, which are
based on actual shares outstanding on the dates of distributions.
*** Annualized.
**** Not annualized.
(1) Reflects waivers and reimbursements.
(2) The amount shown for a share outstanding throughout the period is not
in accord with the change in the aggregate gains and losses in
investments during the period because of the timing of sales and
repurchases of Fund shares in relation to fluctuating net asset value
during the period.
(3) Total return is calculated assuming a purchase of shares on the first
day and a sale of shares on the last day of the period reported and
will include reinvestments of dividends and distributions, if any.
Total return is not annualized.
(4) Without the waiver of advisory, 12b-1, administration and transfer
agent fees and without the reimbursement of certain operating
expenses, the ratio of expenses to average net assets annualized for
the period ended August 31, 1997 would have been 2.64% for the
Institutional Class.
(5) Computed by dividing the total amount of commissions paid by the total
number of shares purchased and sold during the period subject to such
commissions.

-3-

<PAGE>

INVESTMENT OBJECTIVES AND POLICIES
- --------------------------------------------------------------------------------

The Fund's investment objective is to provide long-term growth of capital
with current income as a secondary objective. The Fund seeks to achieve its
objective by investing at least 65% of its total assets in a diversified
portfolio consisting primarily of equity securities, such as common stocks and
securities convertible into common stocks, of issuers with a market
capitalization of $1 billion or greater and identified by the Adviser as
possessing value characteristics.

The Adviser examines various factors in determining the value
characteristics of such issuers, including, but not limited to, price to book
value ratios and price to earnings ratios. These value characteristics are
examined in the context of the issuer's operating and financial fundamentals
such as return on equity, earnings growth and cash flow.

The Adviser selects securities for the Fund based on a continuous study of
trends in industries and companies, earnings power and growth and other
investment criteria. In general, the Fund's investments are broadly diversified
over a number of industries and, as a matter of policy, the Fund will not invest
25% or more of its total assets in any one industry.

The Fund may invest up to 20% of its total assets in securities of foreign
issuers. Investing in securities of foreign issuers involves considerations not
typically associated with investing in securities of companies organized and
operated in the United States. Foreign securities generally are denominated and
pay dividends or interest in foreign currencies. The Fund may hold from time to
time various foreign currencies pending their investment in foreign securities
or their conversion into U.S. dollars. The value of the assets of the Fund as
measured in U.S. dollars may therefore be affected favorably or unfavorably by
changes in exchange rates. There may be less publicly available information
concerning foreign issuers than is available with respect to U.S. issuers.
Foreign securities may not be registered with the U.S. Securities and Exchange
Commission, and generally, foreign companies are not subject to uniform
accounting, auditing and financial reporting requirements comparable to those
applicable to U.S. issuers. See "Investment Objectives and Policies--Foreign
Securities" in the Statement of Additional Information.

The Fund may invest the remainder of its total assets in equity securities
of issuers with lower capitalization; derivative securities; debt securities
issued by U.S. banks, corporations and other business organizations that are
investment grade securities; and debt securities issued by the U.S. Government
or government agencies.

In accordance with the above-mentioned policies, the Fund may also invest
in indexed securities, convertible securities, repurchase and reverse repurchase
agreements and dollar rolls, financial futures contracts, options on futures
contracts and may lend portfolio securities. See "Investment Objectives and
Policies" in the Statement of Additional Information.

The Fund may invest in registered investment companies and investment funds
in foreign countries subject to the provisions of the Investment Company Act of
1940 (the "1940 Act") and as discussed in "Investment Objectives and Policies"
in the Statement of Additional Information. If the Fund invests in such
investment companies, the Fund will bear its proportionate share of the costs
incurred by such companies, including investment advisory fees.

While the Adviser intends to fully invest the Fund's assets at all times in
accordance with the above mentioned policies, the Fund reserves the right to
hold up to 100% of its assets, as a temporary defensive measure, in cash and
eligible U.S. dollar-denominated money market instruments. The Adviser will
determine when market conditions warrant temporary defensive measures.

The Fund's investment objective and the policies described above may be
changed by RBB's Board of Directors without the affirmative vote of the holders
of a majority of the outstanding Shares representing interests in the Fund.

-4-

<PAGE>

INVESTMENT LIMITATIONS
- --------------------------------------------------------------------------------

The Fund may not change the following investment limitations without
shareholder approval. (A complete list of the investment limitations that cannot
be changed without such a vote of the shareholders is contained in the Statement
of Additional Information under "Investment Objectives and Policies.")

The Fund may not:

1. Purchase the securities of any one issuer, other than
securities issued or guaranteed by the U.S. Government or its agencies
or instrumentalities, if immediately after and as a result of such
purchases more than 5% of the value of the Fund's total assets would
be invested in the securities of such issuer, or more than 10% of the
outstanding voting securities of such issuer would be owned by the
Fund, except that up to 25% of the value of the Fund's total assets
may be invested without regard to such limitations.

2. Purchase any securities which would cause, at the time of
purchase, 25% or more of the value of the total assets of the Fund to
be invested in the obligations of issuers in any single industry,
provided that there is no limitation with respect to investments in
U.S. Government obligations.

3. Borrow money or issue senior securities, except that the
Fund may borrow from banks and enter into reverse repurchase
agreements and dollar rolls for temporary purposes in amounts up to
one-third of the value of its total assets at the time of such
borrowing; or mortgage, pledge or hypothecate any assets, except in
connection with any such borrowing and then in amounts not in excess
of one-third of the value of the Fund's total assets at the time of
such borrowing. The Fund will not purchase securities while its
aggregate borrowings (including reverse repurchase agreements, dollar
rolls and borrowings from banks) are in excess of 5% of its total
assets. Securities held in escrow or separate accounts in connection
with the Fund's investment practices are not considered to be
borrowings or deemed to be pledged for purposes of this limitation.

PORTFOLIO TURNOVER

The Fund retains the right to sell securities irrespective of how long they
have been held. The Adviser estimates that the annual turnover in the Fund will
not exceed 100%. High Portfolio turnover (100% or more) will generally result in
higher transaction costs to a Portfolio and may result in the realization of
short-term capital gains that are taxable to shareholders as ordinary income.

RISK FACTORS
- --------------------------------------------------------------------------------

As with other mutual funds, there can be no assurance that the Fund will
achieve its objective. The net asset value per share of Shares representing
interests in the Fund will fluctuate as the values of its portfolio securities
change in response to changing conditions in the equity market. An investment in
the Fund is not intended to constitute a balanced investment program. Other risk
factors are discussed above under "Investment Objectives and Policies" and in
the Statement of Additional Information under "Investment Objectives and
Policies."

Investment methods described in this Prospectus are among those that the
Fund has the power to utilize. Some may be employed on a regular basis; others
may not be used at all. Accordingly, reference to any particular method or
technique carries no implication that it will be utilized or, if it is, that it
will be successful.

-5-

<PAGE>

MANAGEMENT
- --------------------------------------------------------------------------------

BOARD OF DIRECTORS

The business and affairs of RBB and the Fund are managed under the
direction of RBB's Board of Directors.

INVESTMENT ADVISER

Boston Partners Asset Management, L.P., located at One Financial Center,
43rd Floor, Boston, Massachusetts 02111, serves as the Fund's investment
adviser. The Adviser provides investment management and investment advisory
services to investment companies and other institutional accounts that had
aggregate total assets under management as of September 30, 1997, in excess of
$12.5 billion. Boston Partners' general partner is Boston Partners, Inc., a
company that acts as a general partner to investment advisers organized as
limited partnerships.

Subject to the supervision and direction of RBB's Board of Directors, the
Adviser manages the Fund's portfolio in accordance with the Fund's investment
objective and policies, makes investment decisions for the Fund, places orders
to purchase and sell securities, and employs professional portfolio managers and
securities analysts who provide research services to the Fund. For its services
to the Fund, the Adviser is entitled to receive under the Advisory Agreement a
monthly advisory fee computed at an annual rate of 0.75% of the Fund's average
daily net assets. The Adviser is currently waiving advisory fees in excess of
0.08% of the Fund's average daily net assets.

PORTFOLIO MANAGEMENT

The day-to-day portfolio management of the Fund is the responsibility of
Mark E. Donovan and Wayne S. Sharp who are senior portfolio managers of the
Adviser. Mr. Donovan is Chairperson of the Adviser's Equity Strategy Committee
which oversees the investment activities of the Adviser's $4.3 billion of Large
Capitalization Core Value institutional equity assets under management. Prior to
joining the Adviser on April 16, 1995, Mr. Donovan was a Senior Vice President
and Vice Chairman of The Boston Company Asset Management, Inc.'s Equity Policy
Committee. Mr. Donovan is a Chartered Financial Analyst and has over fourteen
years of investment experience. Ms. Sharp is Vice Chairperson of the Adviser's
Equity Strategy Committee and has over twenty years of investment experience.
Prior to joining the Adviser on April 16, 1995, Ms. Sharp was a Senior Vice
President and member of the Equity Policy Committee of The Boston Company Asset
Management, Inc. Ms. Sharp is also a Chartered Financial Analyst.

ADMINISTRATOR

PFPC Inc. ("PFPC") serves as administrator to the Fund and generally
assists the Fund in all aspects of its administration and operations, including
matters relating to the maintenance of financial records and accounting. For its
services, PFPC is entitled to receive a fee under an administration and
accounting services agreement calculated at an annual rate of .125% of the
Fund's average daily net assets with a minimum fee of $75,000 payable monthly on
a pro rata basis. PFPC is currently waiving one-half of its minimum annual fee.

TRANSFER AGENT, DIVIDEND DISBURSING AGENT, AND CUSTODIAN

DISTRIBUTOR

Provident Distributors, Inc. (the "Distributor" or "PDI"), with a principal
business address at Four Falls Corporate Center, 6th Floor, West Conshohocken,
Pennsylvania 19428, acts as distributor for the Shares pursuant to a
distribution agreement (the "Distribution Agreement") with RBB on behalf of the
Shares.

-6-

<PAGE>

ADMINISTRATIVE SERVICES AGENT

PDI also provides certain administrative services to the Institutional
Class of the Fund that are not provided by PFPC. As compensation for such
administrative services, the Fund pays PDI each month a fee for the previous
month calculated at the annual rate of .15% of average daily net assets of the
Institutional Class of the Fund.

EXPENSES

The expenses of the Fund are deducted from its total income before
dividends are paid. Any general expenses of RBB that are not readily
identifiable as belonging to a particular investment portfolio of RBB will be
allocated among all investment portfolios of RBB based upon the relative net
assets of the investment portfolios. The Institutional Class of the Fund may pay
a different share than the other classes of the Fund of other expenses
(excluding advisory and custodial fees) if those expenses are actually incurred
in a different amount by the Institutional Class or if it receives different
services.

The Adviser may assume expenses of the Fund from time to time. To the
extent any service providers assume expenses of the Fund, such assumption of
expenses will have the effect of lowering the Fund's overall expense ratio and
of increasing its yield to investors.

HOW TO PURCHASE SHARES
- --------------------------------------------------------------------------------

GENERAL

Shares representing interests in the Fund are offered continuously for sale
by the Distributor and may be purchased without imposition of a sales charge.
Shares may be purchased initially by completing the application included in this
Prospectus and forwarding the application to the Fund's transfer agent, PFPC.
Purchases of Shares may be effected by wire to an account to be specified by
PFPC or by mailing a check or Federal Reserve Draft, payable to the order of
"The Boston Partners Large Cap Value Fund," c/o PFPC Inc., P.O. Box 8852,
Wilmington, Delaware 19899-8852. Shareholders may not purchase shares of the
Boston Partners Large Cap Value Fund with a check issued by a third party and
endorsed over to the Fund. The name of the Fund, Boston Partners Large Cap Value
Fund, must also appear on the check or Federal Reserve Draft. Federal Reserve
Drafts are available at national banks or any state bank which is a member of
the Federal Reserve System. Initial investments in the Fund must be at least
$100,000 and subsequent investments must be at least $5,000. For purposes of
meeting the minimum initial purchase, clients which are part of endowments,
foundations or other related groups may be aggregated. The Fund reserves the
right to suspend the offering of Shares for a period of time or to reject any
purchase order.

Shares may be purchased on any Business Day. A "Business Day" is any day
that the New York Stock Exchange, Inc. (the "NYSE") is open for business.
Currently, the NYSE is closed on weekends and New Year's Day, Dr. Martin Luther
King, Jr. Day, Presidents' Day, Good Friday, Memorial Day, Independence Day,
Labor Day, Thanksgiving Day and Christmas Day, and on the preceding Friday or
subsequent Monday when one of these holidays falls on a Saturday or Sunday.

The price paid for Shares purchased is based on the net asset value next
computed after a purchase order is received in good order by the Fund or its
agents. Orders received by the Fund or its agents prior to the close of the NYSE
(generally 4:00 p.m. Eastern Time) are priced at that Business Day's net asset
value. Orders received by the Fund or its agents after the close of the NYSE
(generally 4:00 p.m. Eastern Time) are priced at the net asset value next
determined on the following Business Day. In those cases where an investor pays
for Shares by check, the purchase will be effected at the net asset value next
determined after the Fund or its agents receives the order and the completed
application.

-7-

<PAGE>

Shares may be purchased and subsequent investments may be made by
principals and employees of the Adviser, and by their spouses and children,
either directly or through their individual retirement accounts, and by any
pension and profit-sharing plan of the Adviser, without being subject to the
minimum investment limitations.

An investor may also purchase Shares by having his bank or his broker wire
Federal Funds to PFPC. An investor's bank or broker may impose a charge for this
service. The Fund does not currently impose a service charge for effecting wire
transfers but reserves the right to do so in the future. In order to ensure
prompt receipt of an investor's Federal Funds wire for an initial investment, it
is important that an investor follows these steps:

A. Telephone the Fund's transfer agent, PFPC, toll-free (888)
261-4073, and provide PFPC with your name, address, telephone number,
Social Security or Tax Identification Number, the Fund selected, the
amount being wired, and by which bank. PFPC will then provide an
investor with a Fund account number. Investors with existing
accounts should also notify PFPC prior to wiring funds.

B. Instruct your bank or broker to wire the specified amount,
together with your assigned account number, to PFPC's account with PNC:

PNC Bank, N.A.
Philadelphia, PA 19103
ABA NUMBER: 0310-0005-3
CREDITING ACCOUNT NUMBER: 86-1108-2507
FROM: (name of investor)
ACCOUNT NUMBER: (Investor's account number with
the Fund)
FOR PURCHASE OF: Boston Partners Large Cap Value
Fund
AMOUNT: (amount to be invested)

C. Fully complete and sign the application and mail it to the
address shown thereon. PFPC will not process redemptions until it
receives a fully completed and signed Application.

For subsequent investments, an investor should follow steps A and B above.

AUTOMATIC INVESTING

Additional investments in Shares may be made automatically by authorizing
the Fund's transfer agent to withdraw funds from your bank account. Investors
desiring to participate in the automatic investing program should call the
Fund's transfer agent, PFPC, at (888) 261-4073 to obtain the appropriate forms.

HOW TO REDEEM AND EXCHANGE SHARES
- --------------------------------------------------------------------------------

REDEMPTION BY MAIL

Shareholders may redeem for cash some or all of their Shares of the Fund at
any time. To do so, a written request in proper form must be sent directly to
Boston Partners Large Cap Value Fund, c/o PFPC Inc., P.O. Box 8852, Wilmington,
Delaware 19899- 8852. There is no charge for a redemption.

A request for redemption must be signed by all persons in whose names the
Shares are registered. Signatures must conform exactly to the account
registration. If the proceeds of the redemption would exceed $10,000, or if the
proceeds are not to be paid to the record owner at the record address, or if the
shareholder is a corporation, partnership, trust or fiduciary, signature(s) must
be guaranteed according to the procedures described below under "How to Redeem
and Exchange Shares --Exchange Privilege."

-8-

<PAGE>

THIS PAGE INTENTIONALLY LEFT BLANK

<PAGE>

THIS PAGE INTENTIONALLY LEFT BLANK

<PAGE>

Generally, a properly signed written request with any required signature
guarantee is all that is required for a redemption. In some cases, however,
other documents may be necessary. In the case of shareholders holding share
certificates, the certificates for the shares being redeemed must accompany the
redemption request. Additional documentary evidence of authority is also
required by the Fund's transfer agent in the event redemption is requested by a
corporation, partnership, trust, fiduciary, executor or administrator.

INVOLUNTARY REDEMPTION

The Fund reserves the right to redeem a shareholder's account at any time
the net asset value of the account falls below $500 as the result of a
redemption or an exchange request. Shareholders will be notified in writing that
the value of their account is less than $500 and will be allowed 30 days to make
additional investments before the redemption is processed.

PAYMENT OF REDEMPTION PROCEEDS

In all cases, the redemption price is the net asset value per share next
determined after the request for redemption is received in proper form by the
Fund or its agents. Payment for Shares redeemed is made by check mailed within
seven days after acceptance by the Fund or its agents of the request and any
other necessary documents in proper order. Such payment may be postponed or the
right of redemption suspended as permitted by the rules of the SEC. If the
Shares to be redeemed have been recently purchased by check, the Fund's transfer
agent may delay mailing a redemption check, which may be a period of up to 15
days, pending a determination that the check has cleared. The Fund has elected
to be governed by Rule 18f-1 under the 1940 Act so that a portfolio is obligated
to redeem its shares solely in cash up to the lesser of $250,000 or 1% of its
net asset value during any 90-day period for any one shareholder of a portfolio.

EXCHANGE PRIVILEGE

The exchange privilege is available to shareholders residing in any state
in which the Shares being acquired may be legally sold. A shareholder may
exchange Shares of the Fund for Institutional Shares of the Boston Partners Mid
Cap Value Fund or the Boston Partners Bond Fund, subject to restrictions
described under "Exchange Privilege Limitations" below. Such exchange will be
effected at the net asset value of the exchanged Fund and the net asset value of
the Boston Partners Mid Cap Value Fund or Boston Partners Bond Fund next
determined after receipt of a request for an exchange by the Fund or its agents.
An exchange of Shares will be treated as a sale for federal income tax purposes.
See "Taxes." A shareholder wishing to make an exchange may do so by sending a
written request to PFPC.

If the exchanging shareholder does not currently own Institutional Shares
of the Boston Partners Mid Cap Value Fund or Boston Partners Bond Fund, a new
account will be established with the same registration, dividend and capital
gain options as the account from which shares are exchanged, unless otherwise
specified in writing by the shareholder with all signatures guaranteed. A
signature guarantee may be obtained from a domestic bank or trust company,
broker, dealer, clearing agency or savings association who are participants in a
medallion program recognized by the Securities Transfer Association. The three
recognized medallion programs are Securities Transfer Agents Medallion Program
(STAMP), Stock Exchanges Medallion Program (SEMP) and New York Stock Exchange,
Inc. Medallion Signature Program (MSP). Signature guarantees that are not part
of these programs will not be accepted. The exchange privilege may be modified
or terminated at any time, or from time to time, by RBB, upon 60 days' written
notice to shareholders.

If an exchange is to a new account in the Boston Partners Mid Cap Value
Fund or Boston Partners Bond Fund, the dollar value of Shares acquired must
equal or exceed that Fund's minimum for a new account; if to an existing
account, the dollar value must equal or exceed that Fund's minimum for
subsequent investments. If any amount remains in the Fund from which the
exchange is being made, such amount must not drop below the minimum account
value required by the Fund.

-9-
<PAGE>

EXCHANGE PRIVILEGE LIMITATIONS

The Fund's exchange privilege is not intended to afford shareholders a
way to speculate on short-term movements in the market. Accordingly, in order to
prevent excessive use of the exchange privilege that may potentially disrupt the
management of the Fund and increase transactions costs, the Fund has established
a policy of limiting excessive exchange activity.

Shareholders are entitled to six (6) exchange redemptions (at least 30 days
apart) from the Fund during any twelve-month period. Notwithstanding these
limitations, the Fund reserves the right to reject any purchase request
(including purchases by exchange) that is deemed to be disruptive to efficient
portfolio management.

TELEPHONE TRANSACTIONS

In order to request an exchange or redemption by telephone, a shareholder
must have completed and returned an account application containing the
appropriate telephone election. To add a telephone option to an existing account
that previously did not provide for this option, a Telephone Authorization Form
must be filed with PFPC. This form is available from PFPC. Once this election
has been made, the shareholder may simply contact PFPC by telephone to request
the exchange or redemption by calling (888) 261-4073. Neither RBB, the Fund, the
Distributor, the Administrator nor any Fund agent will be liable for any loss,
liability, cost or expense for following RBB's telephone transaction procedures
described below or for following instructions communicated by telephone that
they reasonably believe to be genuine.

RBB's telephone transaction procedures include the following measures: (1)
requiring the appropriate telephone transaction privilege forms; (2) requiring
the caller to provide the names of the account owners, the account social
security number and name of the Fund, all of which must match RBB's records; (3)
requiring RBB's service representative to complete a telephone transaction form,
listing all of the above caller identification information; (4) permitting
exchanges only if the two account registrations are identical; (5) requiring
that redemption proceeds be sent only by check to the account owners of record
at the address of record, or by wire only to the owners of record at the bank
account of record; (6) sending a written confirmation for each telephone
transaction to the owners of record at the address of record within five (5)
Business Days of the call; and (7) maintaining tapes of telephone transactions
for six months, if the Fund elects to record shareholder telephone transactions.
For accounts held of record by broker-dealers (other than the Distributor),
financial institutions, securities dealers, financial planners and other
industry professionals, additional documentation or information regarding the
scope of a caller's authority is required. Finally, for telephone transactions
in accounts held jointly, additional information regarding other account holders
is required. Telephone transactions will not be permitted in connection with IRA
or other retirement plan accounts or by an attorney-in-fact under a power of
attorney.

NET ASSET VALUE
- --------------------------------------------------------------------------------

The net asset values for each class of a fund are calculated by adding the
value of the proportionate interest of the class in a fund's securities, cash
and other assets, deducting the actual and accrued liabilities of the class and
dividing by the result of outstanding shares of the class. The net asset value
of each class are calculated independently of each other class. The net asset
values are calculated as of 4:00 p.m. Eastern Time on each Business Day.

Valuation of securities held by the Fund is as follows: securities traded
on a national securities exchange or on the NASDAQ National Market System are
valued at the last reported sale price that day; securities traded on a national
securities exchange or on the NASDAQ National Market System for which there were
no sales on that day and securities traded on other over-the-counter markets for
which market quotations are readily available are valued at the mean of the bid
and asked prices; and securities for which market quotations are not readily
available are valued at fair market value as determined in good faith by or
under the direction of RBB's Board of Directors. The amortized cost method of
valuation may also be used with respect to debt obligations with sixty days or
less remaining to maturity.

-10-

<PAGE>

With the approval of RBB's Board of Directors, the Fund may use a pricing
service, bank or broker-dealer experienced in such matters to value the Fund's
securities. A more detailed discussion of net asset value and security valuation
is contained in the Statement of Additional Information.

DIVIDENDS AND DISTRIBUTIONS
- --------------------------------------------------------------------------------

The Fund will distribute substantially all of the net investment income and
net realized capital gains, if any, of the Fund to the Fund's shareholders. All
distributions are reinvested in the form of additional full and tractional
Shares unless a shareholder elects otherwise.

The Fund will declare and pay dividends from net investment income annually
and pays them in the calendar year in which they are declared, generally in
December. Net realized capital gains (including net short-term capital gains),
if any, will be distributed at least annually.

TAXES
- --------------------------------------------------------------------------------

The following discussion is only a brief summary of some of the important
tax considerations generally affecting the Fund and its shareholders and is not
intended as a substitute for careful tax planning. Accordingly, investors in the
Fund should consult their tax advisers with specific reference to their own tax
situation.

The Fund will elect to be taxed as a regulated investment company under
Subchapter M of the Internal Revenue Code of 1986, as amended. So long as the
Fund qualifies for this tax treatment, it will be relieved of federal income tax
on amounts distributed to shareholders, but shareholders, unless otherwise
exempt, will pay income or capital gains taxes on amounts so distributed (except
distributions that are treated as a return of capital) regardless of whether
such distributions are paid in cash or reinvested in additional shares.

Distributions out of the "net capital gain" (the excess of net long-term
capital gain over net short-term capital loss), if any, of the Fund, and out of
the portion of such net capital gain that constitutes mid-term capital gain,
will be taxed to shareholders as long-term capital gain or mid-term capital
gain, as the case may be, regardless of the length of time a shareholder has
held his shares, whether such gain was reflected in the price paid for the
shares, or whether such gain was attributable to bonds bearing tax-exempt
interest. All other distributions. to the extent they are taxable, are taxed to
shareholders as ordinary income.

RBB will send written notices to shareholders annually regarding the tax
status of distributions made by the Fund. Dividends declared in December of any
year payable to shareholders of record on a specified date in such a month will
be deemed to have been received by the shareholders on December 31, provided
such dividends are paid during January of the following year. The Fund intends
to make sufficient actual or deemed distributions prior to the end of each
calendar year to avoid liability for federal excise tax.

Investors should be careful to consider the tax implications of buying
shares just prior to a distribution. The price of shares purchased at that time
will reflect the amount of the forthcoming distribution. Those investors
purchasing shares just prior to a distribution will nevertheless be taxed on the
entire amount of the distribution received, although the distribution is, in
effect, a return of capital.

Shareholders who exchange shares representing interests in one Fund for
shares representing interests in another Fund will generally recognize gain or
loss for federal income tax purposes.

Shareholders who are nonresident alien individuals, foreign trusts or
estates, foreign corporations or foreign partnerships may be subject to
different U.S. federal income tax treatment.

-11-

<PAGE>

MULTI-CLASS STRUCTURE
- --------------------------------------------------------------------------------

The Fund offers one other class of shares, Investor Shares, which is
offered directly to individual investors pursuant to a separate prospectus.
Shares of each class represent equal pro rata interests in the Fund and accrue
dividends and calculate net asset value and performance quotations in the same
manner. The Fund will quote performance of the Investor Shares separately from
Institutional Shares. Because of different expenses paid by the Institutional
Shares, the total return on such shares can be expected, at any time, to be
different than the total return on Investor Shares. Information concerning this
other class may be obtained by calling the Fund at (888) 261-4073.

DESCRIPTION OF SHARES
- --------------------------------------------------------------------------------

RBB has authorized capital of thirty billion shares of Common Stock, $.001
par value per share, of which 14.83 billion shares are currently classified into
91 different classes of Common Stock. See "Description of Shares" in the
Statement of Additional Information.

THIS PROSPECTUS AND THE STATEMENT OF ADDITIONAL INFORMATION INCORPORATED
HEREIN RELATE PRIMARILY TO BOSTON PARTNERS LARGE CAP VALUE FUND AND DESCRIBE
ONLY THE INVESTMENT OBJECTIVES AND POLICIES, OPERATIONS, CONTRACTS AND OTHER
MATTERS RELATING TO BOSTON PARTNERS LARGE CAP VALUE FUND.

Each share that represents an interest in the Fund has an equal
proportionate interest in the assets belonging to the Fund with each other share
that represents an interest in the Fund, even where a share has a different
class designation than another share representing an interest in the Fund.
Shares of the Fund do not have preemptive or conversion rights. When issued for
payment as described in this Prospectus, Shares will be fully paid and
non-assessable.

RBB currently does not intend to hold annual meetings of shareholders
except as required by the 1940 Act or other applicable law. The law under
certain circumstances provides shareholders with the right to call for a meeting
of shareholders to consider the removal of one or more directors. To the extent
required by law, the Fund will assist in shareholder communication in such
matters.

Holders of Shares of the Fund will vote in the aggregate and not by class
on all matters, except where otherwise required by law. Further, shareholders of
all investment portfolios of RBB will vote in the aggregate and not by portfolio
except as otherwise required by law or when RBB's Board of Directors determines
that the matter to be voted upon affects only the interests of the shareholders
of a particular investment portfolio. (See the Statement of Additional
Information under "Additional Information Concerning Fund Shares" for examples
when the 1940 Act requires voting by investment portfolio or by class.)
Shareholders of the Fund are entitled to one vote for each full share held
(irrespective of class or portfolio) and fractional votes for fractional shares
held. Voting rights are not cumulative and, accordingly, the holders of more
than 50% of the aggregate shares of Common Stock of the Fund may elect all of
the directors.

As of November 15, 1997, to the Fund's knowledge, no person held of record
or beneficially 25% or more of the outstanding shares of all classes of RBB.

-12-

<PAGE>

OTHER INFORMATION
- --------------------------------------------------------------------------------

REPORTS AND INQUIRIES

Shareholders will receive unaudited semi-annual reports describing the
Fund's investment operations and annual financial statements audited by
independent accountants. Shareholder inquiries should be addressed to The Fund's
transfer agent, PFPC, at Bellevue Park Corporate Center, 400 Bellevue Parkway,
Wilmington, Delaware 19809, toll-tree (888) 261-4073.

SHARE CERTIFICATES

In the interest of economy and convenience, physical certificates
representing Shares in the Fund are not normally issued.

HISTORICAL PERFORMANCE INFORMATION

For the period from commencement of operations (January 2, 1997) through
August 31, 1997, the total return since inception (not annualized) for the
Institutional Class of Shares of the Fund was as follows:

Unannualized investment returns for the period ended
August 31, 1997

Since
INCEPTION
---------
Boston Partners Large Cap Value Fund
(Institutional Shares)................................... 24.60%

The total return assumes reinvestment of all dividends and capital gains
and reflects expense reimbursements and investment advisory fee waivers in
effect. Without these expense reimbursements waivers, the Fund's performance
would have been lower. Of course, past performance is no guarantee of future
results. Investment return and principal value will fluctuate, so that Shares,
when redeemed, may be worth more or less than the original cost. For more
information on performance, see "Performance Information" in the Statement of
Additional Information.

The table below presents the Composite performance history of certain of
the Adviser's managed accounts on an annualized basis for the period ended
August 31, 1997. The Composite is comprised of the Adviser's institutional
accounts and other privately managed accounts with investment objectives,
policies and strategies substantially similar to those of the Fund, although the
accounts have longer operating histories than the Fund, which commenced
operations on January 2, 1997. The Composite performance information includes
the reinvestment of dividends received in the underlying securities and reflects
investment advisory fees. The privately managed accounts in the Composite are
only available to the Adviser's institutional advisory clients. The past
performance of the accounts which comprise the Composite is not indicative of
the future performance of the Fund. These accounts have lower investment
advisory fees than the Fund, and the Composite performance figures would have
been lower if subject to the higher fees and expenses incurred by the Fund.
These private accounts are also not subject to the same investment limitations,
diversification requirements and other restrictions, which are imposed upon
mutual funds under the 1940 Act and the Internal Revenue Code, which, if
imposed, may have adversely affected the performance results of the Composite.
Listed below the performance history for the Composite is a comparative index
comprised of securities similar to those in which accounts contained in the
Composite are invested.

-13-

<PAGE>

Annualized investment returns for the period ended August 31, 1997

Since
ONE YEAR INCEPTION
-------- ---------
Composite Performance............. 46.9% 33.5%*
S&P 500 Stock Index............... 40.7% 28.9%

* The Adviser commenced managing these accounts on June 1, 1995.

The S&P 500 Stock Index is an unmanaged index of 500 selected common
stocks, most of which are listed on the NYSE.

FUTURE PERFORMANCE INFORMATION

From time to time, the Fund may advertise its performance, including
comparisons to other mutual funds with similar investment objectives and to
stock or other relevant indices. All such advertisements will show the average
annual total return over one, five and ten year periods or, if such periods have
not yet elapsed, shorter periods corresponding to the life of the Fund. Such
total return quotations will be computed by finding the compounded average
annual total return for each time period that would equate the assumed initial
investment of $1,000 to the ending redeemable value, net of fees, according to a
required standardized calculation. The standard calculation is required by the
SEC to provide consistency and comparability in investment company advertising.
The Fund may also from time to time include in such advertising an aggregate
total return figure or a total return figure that is not calculated according to
the standardized formula in order to compare more accurately the Fund's
performance with other measures of investment return. For example, the Fund's
total return may be compared with data published by Lipper Analytical Services,
Inc., CDA Investment Technologies, Inc. or Weisenberger Investment Company
Service, or with the performance of the Standard & Poor's 500 Stock Index or the
Dow Jones Industrial Average. Performance information may also include
evaluation of the Fund by nationally recognized ranking services and information
as reported in financial publications such as BUSINESS WEEK, FORTUNE,
INSTITUTIONAL INVESTOR, MONEY MAGAZINE, FORBES, BARRON'S, THE WALL STREET
JOURNAL, THE NEW YORK TIMES, or other national, regional or local publications.
All advertisements containing performance data will include a legend disclosing
that such performance data represents past performance and that the investment
return and principal value of an investment will fluctuate so that an investor's
Shares, when redeemed, may be worth more or less than their original cost.

-14-

<PAGE>

[THIS PAGE INTENTIONALLY LEFT BLANK]

-15-

<PAGE>

NO PERSON HAS BEEN AUTHORIZED TO GIVE ANY INFORMATION
OR MAKE ANY REPRESENTATIONS NOT CONTAINED IN THIS
PROSPECTUS OR IN RBB'S STATEMENT OF ADDITIONAL PROSPECTUS
INFORMATION INCORPORATED HEREIN BY REFERENCE, IN
CONNECTION WITH THE OFFERING MADE BY THIS PROSPECTUS DECEMBER 1, 1997
AND, IF GIVEN OR MADE, SUCH REPRESENTATIONS MUST NOT BE(as revised May 29, 1998)
RELIED UPON AS HAVING BEEN AUTHORIZED BY RBB OR ITS
DISTRIBUTOR. THIS PROSPECTUS DOES NOT CONSTITUTE AN
OFFERING BY RBB OR BY THE DISTRIBUTOR IN ANY
JURISDICTION IN WHICH SUCH OFFERING MAY NOT LAWFULLY BE
MADE.
----------------------

TABLE OF CONTENTS BOSTON PARTNERS
PAGE LARGE CAP
---- VALUE FUND
INTRODUCTION....................................... 2 (INSTITUTIONAL SHARES)
FINANCIAL HIGHLIGHTS............................... 2
INVESTMENT OBJECTIVES AND POLICIES................. 4
INVESTMENT LIMITATIONS............................. 5
RISK FACTORS....................................... 5
MANAGEMENT......................................... 6
HOW TO PURCHASE SHARES............................. 7 bp
HOW TO REDEEM AND EXCHANGE SHARES.................. 8 BOSTON PARTNERS
NET ASSET VALUE.................................... 10 ---------------
DIVIDENDS AND DISTRIBUTIONS........................ 11 ASSET MANAGEMENT, L.P.
TAXES .......................................... 11 ----------------------
MULTI-CLASS STRUCTURE.............................. 12
DESCRIPTION OF SHARES.............................. 12
OTHER INFORMATION.................................. 13

INVESTMENT ADVISER
Boston Partners Asset Management, L.P.
Boston, Massachusetts

CUSTODIAN
PNC Bank, N.A.
Philadelphia, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

ADMINISTRATIVE SERVICES AGENT
Provident Distributors, Inc.
West Conshohocken, Pennsylvania

DISTRIBUTOR
Provident Distributors, Inc.
West Conshohocken, Pennsylvania

COUNSEL
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

INDEPENDENT ACCOUNTANTS
Coopers & Lybrand L.L.P.
Philadelphia, Pennsylvania

(LOGO)
(GRAPHIC OMITTED)

<PAGE>

BOSTON PARTNERS LARGE CAP VALUE FUND bp
(INSTITUTIONAL CLASS) BOSTON PARTNERS ASSET MANAGEMENT, L.P.
--------------------------------------
<TABLE>
<CAPTION>

ACCOUNT APPLICATION
PLEASE NOTE: Do not use this form to open a retirement plan account. For an IRA application or help with this Application, please
call 1-888-261-4073

<S> <C>
- ---------------- (Please check the appropriate box(es) below.)
| 1 | [Checkbox] Individual [Checkbox] Joint Tenant [Checkbox] Other
| Account |
| Registration:| -----------------------------------------------------------------------------------------------------------------
- ---------------- Name SOCIAL SECURITY NUMBER OR TAX ID # OF PRIMARY OWNER

-----------------------------------------------------------------------------------------------------------------
NAME OF JOINT OWNER JOINT OWNER SOCIAL SECURITY NUMBER OR TAX ID #
For joint accounts,the account registrants will be joint tenants with right of survivorship and not tenants in
common unless tenants in common or community property registrations are requested.
- ----------------
GIFT TO MINOR: [Checkbox] UNIFORM GIFTS/TRANSFER TO MINOR'S ACT
- ----------------
-----------------------------------------------------------------------------------------------------------------
NAME OF ADULT CUSTODIAN (ONLY ONE PERMITTED)

-----------------------------------------------------------------------------------------------------------------
NAME OF MINOR (ONLY ONE PERMITTED)

-----------------------------------------------------------------------------------------------------------------
MINOR'S SOCIAL SECURITY NUMBER AND DATE OF BIRTH

- ----------------
CORPORATION,
PARTNERSHIP, TRUST
OR OTHER ENTITY:
- ---------------- -----------------------------------------------------------------------------------------------------------------
NAME OF CORPORATION, PARTNERSHIP, OR OTHER NAME(S) OF TRUSTEE(S)

-----------------------------------------------------------------------------------------------------------------
TAXPAYER IDENTIFICATION NUMBER

- ---------------- -----------------------------------------------------------------------------------------------------------------
| 2 | STREET OR P.O. BOX AND/OR APARTMENT NUMBER
| Mailing |
| Address: | -----------------------------------------------------------------------------------------------------------------
- ---------------- CITY STATE ZIP CODE

-----------------------------------------------------------------------------------------------------------------
DAY PHONE NUMBER EVENING PHONE NUMBER

- ---------------- Minimum initial investment of $100,000 Amount of investment $_______
| 3 |
| Investment | Make the check payable to Boston Partners Large Cap Value Fund.
| Information: |
- ---------------- Shareholders may not purchase shares of this Fund with a check issued by a third party and endorsed over to
the Fund.

- ----------------
DISTRIBUTION NOTE: Dividends and capital gains may be reinvested or paid by check. If not options are selected below, both
OPTIONS: dividends and capital gains will be reinvested in additional Fund shares.
- ----------------
DIVIDENDS [Checkbox] Pay by check [Checkbox] Reinvest [Checkbox] CAPITAL GAINS [Checkbox] Pay by check
[Checkbox] Reinvest

- ---------------- To use this option, you must initial the appropriate line below.
| 4 | I authorize the Transfer Agent to accept instructions from any persons to redeem or exchange shares
| Telephone | in my account(s) by telephone in accordance with the procedures and conditions set forth in the
| Redemption: | Fund's current prospectus.
- ----------------
---------------------------------- -------------------------------Redeem shares, and send the proceeds to
individual initial joint initial the address of record.

---------------------------------- -------------------------------Exchange shares for shares of The Boston
individual initial joint initial Partners Mid Cap Value Fund or Boston
Partners Bond Fund.
</TABLE>

<PAGE>

<S> <C>

- ---------------- The Account Investment Plan, which is available to shareholders of the Fund, makes possible regularly
| 5 | scheduled purchases of Fund shares to allow dollar-cost averaging. The Fund's Transfer Agent can
| Automatic | arrange for an amount of money selected by you to be deducted from your checking account and used to
| Investment | purchase shares of the Fund.
| Plan: |
- ----------------
Please debit $________ from my checking account (named below on or about the 20th of the month.
Please attach an unsigned, voided check.
Monthly [Checkbox] Every Alternate Month [Checkbox] Quarterly [Checkbox] Other [Checkbox]

- ---------------- -----------------------------------------------------------------------------------------------------------------
BANK OF RECORD: BANK NAME STREET ADDRESS OR P.O. BOX
- ----------------
-----------------------------------------------------------------------------------------------------------------
CITY STATE ZIP CODE

-----------------------------------------------------------------------------------------------------------------
BANK ABA NUMBER BANK ACCOUNT NUMBER

Under penalties of perjury, I certify that:

(1) The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to
be issued to me), and
(2) I am not subject to backup withholding because (a) I am exempt from backup withholding, or (b) I have not
been notified by the Internal Revenue Service that I am subject to 31% backup withholding as a result of a
failure to report all interest or dividends, or (c) the IRS 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 THE IRS THAT YOU ARE CURRENTLY SUBJECT TO
BACKUP WITHHOLDING BECAUSE YOU HAVE FAILED TO REPORT ALL INTEREST AND DIVIDENDS ON YOUR TAX RETURN. THE INTERNAL
REVENUE SERVICE DOES NOT REQUIRE YOUR CONSENT TO ANY PROVISION OF THIS DOCUMENT OTHER THAN THE CERTIFICATION
REQUIRED TO AUDIT BACKUP WITHHOLDING.

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF APPLICANT DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF JOINT OWNER DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

(If you are signing for a corporation, you must indicate corporate office or title. If you wish additional
signatories on the account, please include a corporate resolution. If signing as a fiduciary, you must indicate
capacity.)

For information on additional options, such as IRA Applications, rollover requests for qualified retirement
plans, or for wire instructions, please call us at 1-888-261-4073.

MAIL COMPLETED ACCOUNT APPLICATION AND CHECK TO: THE BOSTON PARTNERS LARGE CAP VALUE FUND
C/O PFPC INC.
P.O. BOX 8852
WILMINGTON, DE 19899-8852

</TABLE>

<PAGE>
BOSTON PARTNERS LARGE CAP VALUE FUND
(INVESTOR CLASS)
OF
THE RBB FUND, INC.

Boston Partners Large Cap Value Fund (the "Fund") is an investment
portfolio of The RBB Fund, Inc. ("RBB"), an open-end management investment
company. The shares of the Investor Class ("Shares") offered by this Prospectus
represent interests in the Fund. The Fund is a diversified fund that seeks
long-term growth of capital, with current income as a secondary objective,
primarily through equity investments, such as common stocks and securities
convertible into common stocks. It seeks to achieve its objectives by investing
at least 65% of its total assets in a diversified portfolio consisting of equity
securities of issuers with a market capitalization of primarily $1 billion or
greater and identified by Boston Partners Asset Management, L.P. (the "Adviser")
as equity securities that possess value characteristics. The Adviser examines
various factors in determining the value characteristics of such issuers,
including, but not limited to, price to book value ratios and price to earnings
ratios. These value characteristics are examined in the context of the issuer's
operating and financial fundamentals such as return on equity, earnings growth
and cash flow.

This Prospectus contains information that a prospective investor needs to
know before investing. Please keep it for future reference. A Statement of
Additional Information, dated December 1, 1997, has been filed with the
Securities and Exchange Commission and is incorporated by reference in this
Prospectus. It may be obtained free of charge from the Fund by calling (888)
261-4073. The Prospectus and the Statement of Additional Information are
available for reference, along with other related material, on the SEC Internet
Web Site (http://www.sec.gov).

- --------------------------------------------------------------------------------
THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SECURITIES AND
EXCHANGE COMMISSION OR ANY STATE SECURITIES COMMISSION NOR HAS THE COMMISSION OR
ANY STATE SECURITIES COMMISSION PASSED UPON THE ACCURACY OR ADEQUACY OF THIS
PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

- --------------------------------------------------------------------------------

PROSPECTUS DECEMBER 1, 1997

(as revised May 29, 1998)

<PAGE>

INTRODUCTION
- --------------------------------------------------------------------------------

RBB is an open-end management investment company incorporated under the
laws of the State of Maryland currently operating or proposing to operate
twenty-six separate investment portfolios. The Shares offered by this Prospectus
represent interests in the Boston Partners Large Cap Value Fund. RBB was
incorporated in Maryland on February 29, 1988.

FEE TABLE

The following table illustrates annual operating expenses as a percentage
of average daily net assets incurred by Investor Shares of the Fund (after fee
waivers and expense reimbursements) for the fiscal period ended August 31, 1997,
restated to reflect the expenses that the Fund expects to incur during the
current fiscal year with respect to its Investors Shares. An example based on
the summary is also shown.

ANNUAL FUND OPERATING EXPENSES (AS A PERCENTAGE OF AVERAGE NET ASSETS)

Management Fees (after waivers)*....................0.08%
12b-1 Fees..........................................0.25%
Other Expenses (after waivers and reimbursements)*..0.92%
-----
Total Fund Operating Expenses
(after waivers and expense reimbursements)*........1.25%
=====

* In the absence of expense reimbursements and fee waivers, Management
Fees would be 0.75%, Other Expenses would be 2.05%, and Total Fund
Operating Expenses would be 3.05%. Management Fees and 12b-1 Fees are
each based on average daily net assets and are calculated daily and
paid monthly.

EXAMPLE

An investor would pay the following expenses on a $1,000 investment in the
Fund, assuming (1) a 5% annual return and (2) redemption at the end of each time
period:

ONE THREE FIVE TEN
YEAR YEARS YEARS YEARS
---- ----- ----- -----
Boston Partners Large
Cap Value Fund..........$13 $40 $69 $151

The Fee Table is designed to assist an investor in understanding the
various costs and expenses that an investor in the Fund will bear directly or
indirectly. (For more complete descriptions of the various costs and expenses,
see "Management" and "Distribution of Shares" below.) The Fee Table reflects
expense reimbursements and voluntary waivers of Management Fees and Other
Expenses for the Fund. However, the Adviser and the other service providers are
under no obligation with respect to such expense reimbursements and waivers and
there can be no assurance that any future expense reimbursements and waivers of
Management Fees or Other Expenses will not vary from the figures reflected in
the Fee Table.

FINANCIAL HIGHLIGHTS
- --------------------------------------------------------------------------------

The "Financial Highlights" presented below set forth certain investment
results for shares of the Investor Class of the Fund for the period indicated.
The Investor Class commenced operations on January 16, 1997. The financial data
included in this table should be read in conjunction with the financial
statements and notes thereto and the unqualified

-2-

<PAGE>

report of the independent accountants thereon, which are incorporated by
reference into the Statement of Additional Information. Further information
about the performance of the Investor Class of the Fund is available in the
Annual Report to Shareholders. Both the Statement of Additional Information and
the Annual Report to Shareholders may be obtained from the Fund free of charge
by calling the telephone number on page 1 of the prospectus.

BOSTON PARTNERS LARGE CAP VALUE FUND
(FOR AN INVESTOR SHARE OUTSTANDING THROUGHOUT EACH PERIOD)

FOR THE PERIOD
JANUARY 16, 1997*
THROUGH
AUGUST 31, 1997
---------------

PER SHARE OPERATING PERFORMANCE**
NET ASSET VALUE, BEGINNING OF PERIOD........................ $10.20
------

Net investment income(1).................................... 0.02
Net realized and unrealized gain on investments(2).......... 2.23
-----

Net increase in net assets resulting from operations........ 2.25
-----

NET ASSET VALUE, END OF PERIOD.............................. $12.45
=====

Total investment return(3).................................. 22.06%

RATIOS/SUPPLEMENTAL DATA
Net assets, end of period (000's omitted)................... $683
Ratio of expenses to average net assets***(1)(4)............ 1.11%
Ratio of net investment income to average net assets***(1).. .91%
PORTFOLIO TURNOVER RATE****................................. 67.16%
Average commission rate per share(5)........................ $0.0397

- ----------------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of
the period, except dividends and distributions, it any, which are
based on actual shares outstanding on the dates of distributions.
*** Annualized.
**** Not annualized.
(1) Reflects waivers and reimbursements.
(2) The amount shown for a share outstanding throughout the period is not
in accord with the change in the aggregate gains and losses in
investments during the period because of the timing of sales and
repurchases of Fund shares in relation to fluctuating net asset value
during the period.
(3) Total return is calculated assuming a purchase of shares on the first
day and a sale of shares on the last day of the period reported and
will include reinvestments of dividends and distributions, if any.
Total return is not annualized.
(4) Without the waiver of advisory, 12b-1, administration and transfer
agent fees and without the reimbursement of certain operating
expenses, the ratio of expenses to average net assets annualized for
the period ended August 31, 1997 would have been 3.05% for the
Investor Class.
(5) Computed by dividing the total amount of commissions paid by the total
number of shares purchased and sold during the period subject to such
commissions.

-3-

<PAGE>

INVESTMENT OBJECTIVES AND POLICIES
- --------------------------------------------------------------------------------

The Fund's investment objective is to provide long-term growth of capital
with current income as a secondary objective. The Fund seeks to achieve its
objectives by investing under normal market conditions at least 65% of its total
assets in a diversified portfolio consisting primarily of equity securities,
such as common stocks and securities convertible into common stocks, of issuers
with a market capitalization of $1 billion or greater and identified by the
Adviser as equity securities possessing value characteristics.

The Adviser examines various factors in determining the value
characteristics of such issuers, including but not limited to price to book
value ratios and price to earnings ratios. These value characteristics are
examined in the context of the issuer's operating and financial fundamentals
such as return on equity, earnings growth and cash flow.

The Fund may invest up to 20% of its total assets in securities of foreign
issuers. Investing in securities of foreign issuers involves considerations not
typically associated with investing in securities of companies organized and
operating in the United States. Foreign securities generally are denominated and
pay dividends or interest in foreign currencies. The Fund may hold from time to
time various foreign currencies pending their investment in foreign securities
or their conversion into U.S. dollars. The value of the assets of the Fund as
measured in U.S. dollars may therefore be affected favorably or unfavorably by
changes in exchange rates. There may be less publicly available information
concerning foreign issuers than is available with respect to U.S. issuers.
Foreign securities may not be registered with the U.S. Securities and Exchange
Commission, and generally, foreign companies are not subject to uniform
accounting, auditing and financial reporting requirements comparable to those
applicable to U.S. issuers. See "Investment Objectives and Policies--Foreign
Securities" in the Statement of Additional Information.

The Fund may invest the remainder of its total assets in equity securities
of issuers with lower capitalizations; derivative securities; debt securities
issued by U.S. banks, corporations and other business organizations that are
investment grade securities; and debt securities issued by the U.S. Government
or government agencies.

In accordance with the above-mentioned policies, the Fund may also invest
in indexed securities, convertible securities, repurchase agreements, reverse
repurchase agreements, dollar rolls, financial futures contracts, options on
futures contracts and may lend portfolio securities. See "Investment Objectives
and Policies" in the Statement of Additional Information.

The Fund may invest in registered investment companies and investment funds
in foreign countries subject to the provisions of the Investment Company Act of
1940, as amended (the "1940 Act") and as discussed in "Investment Objectives and
Policies" in the Statement of Additional Information. If the Fund invests in
such investment companies, the Fund will bear its proportionate share of the
costs incurred by such companies, including investment advisory fees.

While the Adviser intends to fully invest the Fund's assets at all times in
accordance with the above-mentioned policies, the Fund reserves the right to
hold up to 100% of its assets, as a temporary defensive measure, in cash and
eligible U.S. dollar-denominated money market instruments. The Adviser will
determine when market conditions warrant temporary defensive measures.

The Fund's investment objectives and the policies described above may be
changed by RBB's Board of Directors without the affirmative vote of the holders
of a majority of the outstanding Shares representing interests in the Fund.

-4-

<PAGE>

INVESTMENT LIMITATIONS
- --------------------------------------------------------------------------------

The Fund may not:

1. Purchase the securities of any one issuer, other than
securities issued or guaranteed by the U.S. Government or its agencies
or instrumentalities, if immediately after and as a result of such
purchase, more than 5% of the value of the Fund's total assets would be
invested in the securities of such issuer, or more than 10% of the
outstanding voting securities of such issuer would be owned by the
Fund, except that up to 25% of the value of the Fund's total assets may
be invested without regard to such limitations.

2. Purchase any securities which would cause, at the time of
purchase, more than 25% of the value of the total assets of the Fund to
be invested in the obligations of issuers in any single industry,
provided that there is no limitation with respect to investments in
U.S. Government obligations.

3. Borrow money or issue senior securities, except that the
Fund may borrow from banks and enter into reverse repurchase agreements
and dollar rolls for temporary purposes in amounts up to one-third of
the value of its total assets at the time of such borrowing; or
mortgage, pledge or hypothecate any assets, except in connection with
any such borrowing and then in amounts not in excess of one-third of
the value of the Fund's total assets at the time of such borrowing. The
Fund will not purchase securities while its aggregate outstanding
borrowings (including reverse repurchase agreements, dollar rolls and
borrowings from banks) are in excess of 5% of its total assets.
Securities held in escrow or separate accounts in connection with the
Fund's investment practices are not considered to be borrowings or
deemed to be pledged for purposes of this limitation.

PORTFOLIO TURNOVER

The Fund retains the right to sell securities irrespective of how long
they have been held. The Adviser estimates that the annual turnover in the Fund
will not exceed 100%. High Portfolio turnover (100% or more) will generally
result in higher transaction costs to a portfolio and may result in the
realization of short-term capital gains that are taxable to shareholders as
ordinary income.

RISK FACTORS
- --------------------------------------------------------------------------------

As with other mutual funds, there can be no assurance that the Fund
will achieve its objectives. The net asset value per share of Shares
representing interests in the Fund will fluctuate as the values of its portfolio
securities change in response to changing conditions in the equity market. An
investment in the Fund is not intended to constitute a balanced investment
program. Other risk factors are discussed above under "Investment Objectives and
Policies" and in the Statement of Additional Information under "Investment
Objectives and Polices."

Investment methods described in this Prospectus are among those which
the Fund has the power to utilize. Some may be employed on a regular basis;
others may not be used at all. Accordingly, reference to any particular method
or technique carries no implication that it will be utilized or, if it is, that
it will be successful.

-5-

<PAGE>

MANAGEMENT
- --------------------------------------------------------------------------------

BOARD OF DIRECTORS

The business and affairs of RBB and the Fund are managed under the
direction of RBB's Board of Directors.

INVESTMENT ADVISER

Boston Partners Asset Management, L.P. located at One Financial Center,
43rd Floor Boston, Massachusetts 02111, serves as the Fund's investment adviser.
The Adviser provides investment management and investment advisory services to
investment companies and other institutional accounts that had aggregate total
assets under management as of September 30, 1997, in excess of $12.5 billion.
Boston Partners' general partner is Boston Partners, Inc., a company that acts
as a general partner to investment advisers organized as limited partnerships.

Subject to the supervision and direction of RBB's Board of Directors, the
Adviser manages the Fund's portfolio in accordance with the Fund's investment
objectives and policies, makes investment decisions for the Fund, places orders
to purchase and sell securities, and employs professional portfolio managers and
securities analysts who provide research services to the Fund. For its services
to the Fund, the Adviser is entitled to receive under the Advisory Agreement a
monthly advisory fee computed at an annual rate of 0.75% of the Fund's average
daily net assets. The Adviser is currently waiving advisory fees in excess of
0.80% of the Fund's average daily net assets.

PORTFOLIO MANAGEMENT

ADMINISTRATOR

PFPC Inc. ("PFPC") serves as administrator to the Fund and generally
assists the Fund in all aspects of its administration and operations, including
matters relating to the maintenance of financial records and accounting. For its
services, PFPC is entitled to receive a fee under an administration and
accounting services agreement calculated at an annual rate of .125% of the
Fund's average daily net assets with a minimum annual fee of $75,000 payable
monthly on a pro rata basis. PFPC is currently waiving one-half of its minimum
annual fee.

TRANSFER AGENT, DIVIDEND DISBURSING AGENT, AND CUSTODIAN

PNC Bank, National Association ("PNC Bank") serves as the Fund's custodian
and PFPC serves as the Fund's transfer agent and dividend disbursing agent. The
principal offices of PFPC, an indirect, wholly-owned subsidiary of PNC Bank, are
located at 400 Bellevue Parkway, Wilmington, Delaware 19809. PFPC may enter into
shareholder servicing agreements with registered broker-dealers who have entered
into dealer agreements with the Distributor ("Authorized Dealers") for the
provision of certain shareholder support services to customers of such
Authorized Dealers who are shareholders of the Fund. The services provided and
the fees payable by the Fund for these services are described in the Statement
of Additional Information under "Investment Advisory, Distribution and Servicing
Arrangements."

-6-

<PAGE>

DISTRIBUTOR

Provident Distributors, Inc. (the "Distributor"), with a principal business
address at Four Falls Corporate Center, 6th Floor, West Conshohocken,
Pennsylvania 19428, acts as distributor for the Shares pursuant to a
distribution agreement (the "Distribution Agreement") with RBB on behalf of the
Shares.

EXPENSES

The expenses of the Fund are deducted from its total income before
dividends are paid. Any general expenses of RBB that are not readily
identifiable as belonging to a particular investment portfolio of RBB will be
allocated among all investment portfolios of RBB based upon the relative net
assets of the investment portfolios. The Investor Class of the Fund pays its own
distribution fees, and may pay a different share than the other classes of the
Fund of other expenses (excluding advisory and custodial fees) if those expenses
are actually incurred in a different amount by the Investor Class or if it
receives different services.

DISTRIBUTION OF SHARES
- --------------------------------------------------------------------------------

The Board of Directors of RBB has approved and adopted a Distribution
Agreement and Plan of Distribution for the Shares (the "Plan") pursuant to Rule
12b-1 under the 1940 Act. Under the Plan, the Distributor is entitled to receive
from the Fund a distribution fee with respect to the Shares, which is accrued
daily and paid monthly, of up to 0.25% on an annualized basis of the average
daily net assets of the Shares. The actual amount of such compensation under the
Plan is agreed upon by RBB's Board of Directors and by the Distributor in the
Distribution Agreement. The Distributor may, in its discretion, from time to
time waive voluntarily all or any Portion of its distribution fee.

Amounts paid to the Distributor under the Plan may be used by the
Distributor to cover expenses that are related to (i) the sale of the Shares,
(ii) ongoing servicing and/or maintenance of the accounts of Shareholders, and
(iii) sub-transfer agency services, subaccounting services or administrative
services related to the sale of the Shares, all as set forth in the Plan. The
Distributor may delegate some or all of these functions to Service Agents. See
"How to Purchase Shares--Purchases Through Intermediaries."

The Plan obligates the Fund, during the period it is in effect, to accrue
and pay to the Distributor on behalf of the Shares the fee agreed to under the
Distribution Plan. Payments under the Plan are not tied exclusively to expenses
actually incurred by the Distributor, and payments may exceed distribution
expenses actually incurred.

PURCHASES THROUGH INTERMEDIARIES.

Shares of the Fund may be available through certain brokerage firms,
financial institutions and programs sponsored by other industry professionals
(collectively, "Service Organizations"). Certain features of the Shares, such as
the initial and subsequent investment minimums and certain trading restrictions,
may be modified or waived by Service Organizations. Service Organizations may
impose transaction or administrative charges or other direct fees, which charges
or fees would not be imposed if Shares are purchased directly from the Fund.
Therefore, a client or customer should contact the Service Organization acting
on his behalf concerning the fees (if any) charged in connection with a purchase
or redemption of Shares and should read this Prospectus in light of the terms
governing his accounts with the Service Organization. Service Organizations will
be responsible for promptly transmitting client or customer purchase and
redemption orders to the Fund in accordance with their agreements with clients
or customers. Service Organizations or, if applicable, their designees that have
entered into agreements with the Fund or its agent may enter confirmed purchase
orders on behalf of clients and customers, with payment to follow no later than
the Fund's pricing
-7-

<PAGE>

on the following Business Day. If payment is not received by such time, the
Service Organization could be held liable for resulting fees or losses. The Fund
will be deemed to have received a purchase or redemption order when a Service
Organization, or, if applicable, its authorized designee, accepts a purchase or
redemption order in good order. Orders received by the Fund in good order will
be priced at the Fund's net asset value next computed after they are accepted by
the Service Organization or its authorized designee.

For administration, subaccounting, transfer agency and/or other services,
the Adviser or the Distributor or their affiliates may pay Service Organizations
and certain recordkeeping organizations with whom they have entered into
agreements a fee of up to .35% (the "Service Fee') of the average annual value
of accounts with the Fund maintained by such Service Organizations or
recordkeepers. The Service Fee payable to any one Service Organization or
recordkeeper is determined based upon a number of factors, including the nature
and quality of the services provided, the operations processing requirements of
the relationship and the standardized fee schedule of the Service Organization
or recordkeeper.

The Adviser, the Distributor or either of their affiliates may, at their
own expense, provide promotional incentives for qualified recipients who support
the sale of Shares consisting of securities dealers who have sold Shares, or
others, including banks and other financial institutions, under special
arrangements. Incentives may include opportunities to attend business meetings,
conferences, sales or training programs for recipients, employees or clients and
other programs or events and may also include opportunities to participate in
advertising or sales campaigns and/or shareholder services and programs
regarding one or more Boston Partners Funds. Travel, meals and lodging may also
be paid in connection with these promotional activities. In some instances,
these incentives may be offered only to certain institutions whose
representatives provide services in connection with the sale or expected sale of
significant amounts of Shares.

HOW TO PURCHASE SHARES
- --------------------------------------------------------------------------------

GENERAL

Shares representing interests in the Fund are offered continuously for sale
by the Distributor and may be purchased without imposition of a sales charge.
Shares may be purchased initially by completing the application included in this
Prospectus and forwarding the application to the Fund's transfer agent, PFPC.
Purchases of Shares may be effected by wire to an account to be specified by
PFPC or by mailing a check or Federal Reserve Draft, payable to the order of
"The Boston Partners Large Cap Value Fund," c/o PFPC Inc., P.O. Box 8852,
Wilmington, Delaware 19899-8852. The name of the Fund, Boston Partners Large Cap
Value Fund, must also appear on the check or Federal Reserve Draft. Shareholders
may not purchase shares of the Boston Partners Large Cap Value Fund with a check
issued by a third party and endorsed over to the Fund. Federal Reserve Drafts
are available at national banks or any state bank which is a member of the
Federal Reserve System. Initial investments in the Fund must be at least $2,500
and subsequent investments must be at least $100. The Fund reserves the right to
suspend the offering of Shares for a period of time or to reject any purchase
order.

Shares may be purchased on any Business Day. A "Business Day" is any day
that the New York Stock Exchange, Inc. (the "NYSE") is open for business.
Currently, the NYSE is closed on weekends and New Year's Day, Dr. Martin Luther
King, Jr. Day, Presidents' Day, Good Friday, Memorial Day, Independence Day,
Labor Day, Thanksgiving Day and Christmas Day and on the preceding Friday or
subsequent Monday when one of these holidays falls on a Saturday or Sunday.

The price paid for Shares purchased is based on the net asset value next
computed after a purchase order is received in good order by the Fund or its
agents. Orders received by the Fund or its

-8-

<PAGE>

agents prior to the close of the NYSE (generally 4:00 p.m. Eastern Time) are
priced at that Business Day's net asset value. Orders received by the Fund or
its agents after the close of the NYSE are priced at the net asset value next
determined on the following Business Day. In those cases where an investor pays
for Shares by check, the purchase will be effected at the net asset value next
determined after the Fund or its agents receives the order and the completed
application.

Provided that the investment is at least $2,500, an investor may also
purchase Shares by having his bank or her broker wire Federal Funds to PFPC. An
investor's bank or broker may impose a charge for this service. The Fund does
not currently impose a service charge for effecting wire transfers, but reserves
the right to do so in the future. In order to ensure prompt receipt of an
investor's Federal Funds wire for an initial investment, it is important that an
investor follows these steps:

A. Telephone the Fund's transfer agent, PFPC, toll-free (888)
261-4073, and provide PFPC with your name, address, telephone number,
Social Security or Tax Identification Number, the Fund selected, the amount
being wired, and by which bank. PFPC will then provide an investor with a
Fund account number. Investors with existing accounts should also notify
PFPC prior to wiring funds.

B. Instruct your bank or broker to wire the specified amount,
together with your assigned account number, to PFPC's account with PNC
Bank:

PNC Bank, N.A.
Philadelphia, PA 19103
ABA NUMBER: 0310-0005-3
CREDITING ACCOUNT NUMBER: 86-1108-2507
FROM: (name of investor)
ACCOUNT NUMBER: (Investor's account number
with the Fund)
FOR PURCHASE OF: Boston Partners Large Cap
Value Fund
AMOUNT: (amount to be invested)

C. Fully complete and sign the application and mail it to the
address shown thereon. PFPC will not process redemptions until it receives
a fully completed and signed application.

For subsequent investments, an investor should follow steps A and B above.

AUTOMATIC INVESTING

Additional investments in Shares may be made automatically by authorizing
the Fund's transfer agent to withdraw funds from your bank account. Investors
desiring to participate in the Automatic Investment Plan should call the Fund's
transfer agent, PFPC, at (888) 261-4073 to obtain the appropriate forms.

RETIREMENT PLANS

Shares may be purchased in conjunction with individual retirement accounts
("IRAs") and rollover IRAs where PNC Bank acts as Custodian. For further
information as to applications and annual fees, contact PFPC at (888) 261-4073.
To determine whether the benefits of an IRA are available and/or appropriate, a
shareholder should consult with a tax adviser.

HOW TO REDEEM AND EXCHANGE SHARES
- --------------------------------------------------------------------------------

REDEMPTION BY MAIL

-9-

<PAGE>

A request for redemption must be signed by all persons in whose names the
Shares are registered. Signatures must conform exactly to the account
registration. It the proceeds of the redemption would exceed $10,000, or if the
proceeds are not to be paid to the record owner at the record address, or it the
shareholder is a corporation, partnership, trust or fiduciary, signature(s) must
be guaranteed according to the procedures described below under "How to Redeem
and Exchange Shares -- Exchange Privilege."

SYSTEMATIC WITHDRAWAL PLAN

If your account has a value of at least $10,000, you may establish a
Systematic Withdrawal Plan and receive regular periodic payments. A request to
establish a Systematic Withdrawal Plan must be submitted in writing to PFPC at
P.O. Box 8852, Wilmington, Delaware 19899-8852. Each withdrawal redemption will
be processed on or about the 25th of the month and mailed as soon as possible
thereafter. There are no service charges for maintenance, the minimum amount
that you may withdraw each period is $100. (This is merely the minimum amount
allowed and should not be mistaken for a recommended amount.) The holder of a
Systematic Withdrawal Plan will have any income dividends and any capital gains
distributions reinvested in full and fractional shares at net asset value. To
provide funds for payment, Shares will be redeemed in such amount as is
necessary at the redemption price, which is net asset value next determined
after the Fund's receipt of a redemption request. Redemption of Shares may
reduce or possibly exhaust the Shares in your account, particularly in the event
of a market decline. As with other redemptions, a redemption to make a
withdrawal payment is a sale for federal income tax purposes. Payments made
pursuant to a Systematic Withdrawal Plan cannot be considered as actual yield or
income since part of such payments may be a return of capital.

You will ordinarily not be allowed to make additional investments of less
than the aggregate annual withdrawals under the Systematic Withdrawal Plan
during the time you have the plan in effect and, while a Systematic Withdrawal
Plan is in effect, you may not make periodic investments under the Automatic
Investment Plan. You will receive a confirmation of each transaction showing the
sources of the payment and the Share and cash balance remaining in your plan.
The plan may be terminated on written notice by the shareholder or by the Fund
and will terminate automatically if all Shares are liquidated or withdrawn from
the account or upon the death or incapacity of the shareholder. You may change
the amount and schedule of withdrawal payments or suspend such payments by
giving written notice to the Fund's transfer agent at least seven Business Days
prior to the end of the month preceding a scheduled payment.

INVOLUNTARY REDEMPTION

PAYMENT OF REDEMPTION PROCEEDS

In all cases, the redemption price is the net asset value per share next
determined after the request for redemption is received in proper form by the
Fund or its agents. Payment for Shares redeemed is made by check mailed within
seven days after acceptance by the Fund or its agents of the request and any
other necessary documents in proper order. Such payment may be postponed or the
right of redemption suspended as permitted by the 1940 Act. If the Shares to be
redeemed have been recently purchased by check, the Fund's transfer agent may
delay mailing a redemption check, which may be a period of up to 15 days,
pending a determination that the check has cleared. The Fund has

-10-

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>
(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

elected to be governed by Rule 18f-1 under the 1940 Act so that it is obligated
to redeem its shares solely in cash up to the lesser of $250,000 or 1% of its
net asset value during any 90-day period for any one shareholder of a portfolio.

EXCHANGE PRIVILEGE

The exchange privilege will be available to shareholders residing in any
state in which the Shares being acquired may be legally sold. A shareholder may
exchange Shares of the Fund for Investor Shares of the Boston Partners Mid Cap
Value Fund or the Boston Partners Bond Fund, subject to the restrictions
described under "Exchange Privilege Limitations" below. Such exchange will be
effected at the net asset value of the exchanged Fund and the net asset value of
the Boston Partners Mid Cap Value Fund or Boston Partners Bond Fund next
determined after receipt of a request for an exchange by the Fund or its agents.
An exchange of Shares will be treated as a sale for federal income tax purposes.
See "Taxes." A Shareholder wishing to make an exchange may do so by sending a
written request to PFPC.

If the exchanging shareholder does not currently own Investor Shares of the
Boston Partners Mid Cap Value Fund or Boston Partners Bond Fund, a new account
will be established with the same registration, dividend and capital gain
options as the account from which shares are exchanged, unless otherwise
specified in writing by the shareholder with all signatures guaranteed. A
signature guarantee may be obtained from a domestic bank or trust company,
broker, dealer, clearing agency or savings association who are participants in a
medallion program recognized by the Securities Transfer Association. The three
recognized medallion programs are Securities Transfer Agents Medallion Program
(STAMP), Stock Exchanges Medallion Program (SEMP) and New York Stock Exchange,
Inc. Medallion Signature Program (MSP). Signature guarantees that are not part
of these programs will not be accepted. The exchange privilege may be modified
or terminated at any time, or from time to time, by RBB, upon 60 days' written
notice to shareholders.

If an exchange is to a new account in the Boston Partners Mid Cap Value
Fund or Boston Partners Bond Fund, the dollar value of Investor Shares acquired
must equal or exceed that Fund's minimum for a new account; if to an existing
account, the dollar value must equal or exceed that Fund's minimum for
subsequent investments. If any amount remains in the Fund from which the
exchange is being made, such amount must not drop below the minimum account
value required by the Fund.

EXCHANGE PRIVILEGE LIMITATIONS

The Fund's exchange privilege is not intended to afford shareholders a way
to speculate on short-term movements in the market. Accordingly, in order to
prevent excessive use of the exchange privilege that may potentially disrupt the
management of the Funds and increase transactions costs, the Fund has
established a policy of limiting excessive exchange activity.

TELEPHONE TRANSACTIONS

In order to request an exchange or redemption by telephone, a shareholder
must have completed and returned an account application containing the
appropriate telephone election. To add a telephone exchange feature to an
existing account that previously did not provide for this option, a Telephone
Authorization Form must be filed with PFPC. This form is available from PFPC.
Once this election has been made, the shareholder may simply contact PFPC by
telephone to request the exchange or redemption by calling (888) 261-4073.
Neither RBB, the Fund, the Distributor, the Administrator nor any other Fund
agent will be liable for any loss, liability, cost or expense for following
RBB's telephone transaction procedures described below or for following
instructions communicated by telephone that they reasonably believe to be
genuine.

-11-

<PAGE>

NET ASSET VALUE
- --------------------------------------------------------------------------------

The net asset values for each class of a fund are calculated by adding the
value of the proportionate interest of the class in a Fund's cash, securities
and other assets, deducting actual and accrued liabilities of the class and
dividing the result by the number of outstanding shares of the class. The net
asset values of each class are calculated independently from each other class.
The net asset values are calculated as of the close of regular trading on the
NYSE, generally 4:00 p.m. Eastern Time on each Business Day.

DIVIDENDS AND DISTRIBUTIONS
- --------------------------------------------------------------------------------

The Fund will distribute substantially all of the net investment income and
net realized capital gains, if any, of the Fund to the Fund's shareholders. All
distributions are reinvested in the form of additional full and fractional
shares unless a shareholder elects otherwise.

The Fund will declare and pay dividends from net investment income
annually, and pays them in the calendar year in which they are declared,
generally in December. Net realized capital gains (including net short-term
capital gains), if any, will be distributed at least annually.

-12-

<PAGE>

TAXES
- --------------------------------------------------------------------------------

Distributions out of the "net capital gain" (the excess of net long-term
capital gain over net short-term capital loss), it any, of the Fund, and out of
the portion of such net capital gain that constitutes mid-term capital gain,
will be taxed to shareholders as long-term capital gain or mid-term capital
gain, as the case may be, regardless of the length of time a shareholder has
held his shares, whether such gain was reflected in the price paid for the
shares, or whether such gain was attributable to bonds bearing tax-exempt
interest. All other distributions, to the extent they are taxable, are taxed to
shareholders as ordinary income.

Investors should be careful to consider the tax implications of buying
shares just prior to a distribution. The price of shares purchased at that time
will reflect the amount of the forthcoming distribution. Those investors
purchasing shares immediately prior to a distribution will nevertheless be taxed
on the entire amount of the distribution received, although the distribution is,
in effect, a return of capital.

Shareholders who exchange shares representing interests in one Fund for
shares representing interests in another Fund will generally recognize gain or
loss for federal income tax purposes.

Shareholders who are nonresident alien individuals, foreign trusts or
estates, foreign corporations or foreign partnerships may be subject to
different U.S. federal income tax treatment.

MULTI-CLASS STRUCTURE
- --------------------------------------------------------------------------------

The Fund offers one other class of shares, Institutional Shares, which is
offered directly to institutional investors pursuant to a separate prospectus.
Shares of each class represent equal pro rata interests in the Fund and accrue
dividends and calculate net asset value and performance quotations in the same
manner. The Fund will quote performance of the Institutional Shares separately
from Investor Shares. Because of different expenses paid by the Investor Shares,
the total return on such shares can be expected. at any time, to be different
than the total return on Institutional Shares. Information concerning these
other classes may be obtained by calling the Fund at (888) 261-4073.

-13-

<PAGE>

DESCRIPTION OF SHARES
- --------------------------------------------------------------------------------

THIS PROSPECTUS AND THE STATEMENT OF ADDITIONAL INFORMATION INCORPORATED
HEREIN RELATE PRIMARILY TO THE BOSTON PARTNERS LARGE CAP VALUE FUND AND DESCRIBE
ONLY THE INVESTMENT OBJECTIVES AND POLICIES, OPERATIONS, CONTRACTS AND OTHER
MATTERS RELATING TO THE BOSTON PARTNERS LARGE CAP VALUE FUND.

Each share that represents an interest in the Fund has an equal
proportionate interest in the assets belonging to the Fund with each other share
that represents an interest in the Fund, even where a share has a different
class designation than another share representing an interest in that portfolio.
Shares of the Fund do not have preemptive or conversion rights. When issued for
payment as described in this Prospectus, Shares will be fully paid and
non-assessable.

RBB currently does not intend to hold annual meetings of shareholders
except as required by the 1940 Act or other applicable law. The law under
certain circumstances provides shareholders with the right to call for a meeting
of shareholders to consider the removal of one or more directors. To the extent
required by law, RBB will assist in shareholder communication in such matters.

Holders of Shares of the Fund will vote in the aggregate and not by class
on all matters, except where otherwise required by law. Further, shareholders of
all investment portfolios of RBB will vote in the aggregate and not by portfolio
except as otherwise required by law or when RBB's Board of Directors determines
that the matter to be voted upon affects only the interests of the shareholders
of a particular investment portfolio. (See the Statement of Additional
Information under "Additional Information Concerning Fund Shares" for examples
of when the 1940 Act requires voting by investment portfolio or by class.)
Shareholders of the Fund are entitled to one vote for each full share held
(irrespective of class or portfolio) and fractional votes for fractional shares
held. Voting rights are not cumulative and, accordingly, the holders of more
than 50% of the aggregate shares of Common Stock of the Fund may elect all of
the directors.

As of November 15, 1997 to the Fund's knowledge, no person held of record
or beneficially 25% or more of the outstanding shares of all classes of RBB.

OTHER INFORMATION
- --------------------------------------------------------------------------------

REPORTS AND INQUIRIES

Shareholders will receive unaudited semi-annual reports describing the
Fund's investment operations and annual financial statements audited by
independent accountants. Shareholder inquiries should be addressed to the Fund's
transfer agent, PFPC, at Bellevue Park Corporate Center, 400 Bellevue Parkway,
Wilmington, Delaware 19809, toll-free (888) 261-4073.

SHARE CERTIFICATES

In the interest of economy and convenience, physical certificates
representing shares in the Fund are not normally issued.

-14-

<PAGE>

HISTORICAL PERFORMANCE INFORMATION

For the period from commencement of operations (January 16, 1997) through
August 31, 1997, the total return since inception (not annualized) for the
Investor Class of Shares of the Fund was as follows:

Unannualized investment returns for the period ended August 31, 1997

Since
INCEPTION
---------
Boston Partners Large Cap Value Fund
(Investor Shares)........................ 22.06%

The total return assumes the reinvestment of all dividends and capital
gains and reflects expense reimbursements and investment advisory fee and 12b-1
fee waivers in effect. Without these expense reimbursements and waivers, the
Fund's performance would have been lower. Of course, past performance is no
guarantee of future results. Investment return and principal value will
fluctuate, so that Shares, when redeemed, may be worth more or less than the
original cost. For more information on performance, see "Performance
Information" in the Statement of Additional Information.

The table below presents the Composite performance history of certain of
the Adviser's managed accounts on an annualized basis for the period ended
August 31, 1997. The Composite is comprised of the Adviser's institutional
accounts and other privately managed accounts with investment objectives,
policies and strategies substantially similar to those of the Fund, although the
accounts have longer operating histories than the Fund, which commenced
operations on January 16, 1997. The Composite performance information includes
the reinvestment of dividends received in the underlying securities and reflects
the payment of investment advisory fees. The privately managed accounts in the
Composite are only available to the Adviser's institutional advisory clients.
The past performance of the funds and accounts which comprise the Composite is
not indicative of or a substitute for the future performance of the Fund. These
accounts have lower investment advisory fees than the Fund, and the Composite
performance figures would have been lower if subject to the higher fees and
expenses incurred by the Fund. These private accounts are also not subject to
the same investment limitations, diversification requirements and other
restrictions which are imposed upon mutual funds under the 1940 Act and the
Internal Revenue Code, which, if imposed, may have adversely affected the
performance results of the Composite. Listed below the performance history for
the Composite is a comparative index comprised of securities similar to those in
which accounts contained in the Composite are invested.

Annualized investment returns for the period ended August 31, 1997

Since
ONE YEAR INCEPTION
-------- ---------
Composite Performance....................... 46.9% 33.5%*
S&P 500 Stock Index......................... 40.7% 28.9%

* The Adviser commenced managing these accounts on June 1, 1995.

The S&P 500 Stock Index is an unmanaged index of 500 selected common
stocks, most of which are listed on the NYSE.

-15-

<PAGE>

FUTURE PERFORMANCE INFORMATION

-16-

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

NO PERSON HAS BEEN AUTHORIZED TO GIVE ANY INFORMATION
OR MAKE ANY REPRESENTATIONS NOT CONTAINED IN THIS
PROSPECTUS OR IN RBB'S STATEMENT OF ADDITIONAL
INFORMATION INCORPORATED HEREIN BY REFERENCE, IN PROSPECTUS
CONNECTION WITH THE OFFERING MADE BY THIS PROSPECTUS
AND, IF GIVEN OR MADE, SUCH REPRESENTATIONS MUST NOT BE DECEMBER 1, 1997
RELIED UPON AS HAVING BEEN AUTHORIZED BY RBB OR ITS (as revised
DISTRIBUTOR. THIS PROSPECTUS DOES NOT CONSTITUTE AN May 29, 1998)
OFFERING BY RBB OR BY THE DISTRIBUTOR IN ANY
JURISDICTION IN WHICH SUCH OFFERING MAY NOT LAWFULLY BE
MADE.
----------------------

TABLE OF CONTENTS
BOSTON PARTNERS
PAGE LARGE CAP
---- VALUE FUND
INTRODUCTION........................................ 2 (INVESTOR SHARES)
FINANCIAL HIGHLIGHTS................................ 2
INVESTMENT OBJECTIVES AND POLICIES.................. 4
INVESTMENT LIMITATIONS.............................. 5
RISK FACTORS........................................ 5
MANAGEMENT.......................................... 6
DISTRIBUTION OF SHARES.............................. 7 bp
HOW TO PURCHASE SHARES.............................. 8 BOSTON PARTNERS
HOW TO REDEEM AND EXCHANGE SHARES................... 9 ---------------
NET ASSET VALUE..................................... 12 ASSET MANAGEMENT, L.P.
DIVIDENDS AND DISTRIBUTIONS......................... 12 ----------------------
TAXES ........................................... 13
MULTI-CLASS STRUCTURE............................... 13
DESCRIPTION OF SHARES............................... 14
OTHER INFORMATION................................... 14

INVESTMENT ADVISER
Boston Partners Asset Management, L.P.
Boston, Massachusetts

CUSTODIAN
PNC Bank, N.A.
Philadelphia, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

DISTRIBUTOR
Provident Distributors, Inc.
West Conshohocken, Pennsylvania

COUNSEL
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

INDEPENDENT ACCOUNTANTS
Coopers & Lybrand L.L.P.
Philadelphia, Pennsylvania

(LOGO)
(GRAPHIC OMITTED)

<PAGE>

BOSTON PARTNERS LARGE CAP VALUE FUND bp
(INVESTOR CLASS) BOSTON PARTNERS ASSET MANAGEMENT, L.P.
--------------------------------------

ACCOUNT APPLICATION
PLEASE NOTE: Do not use this form to open a retirement plan account. For an IRA application or help with this Application, please
call 1-888-261-4073.

<S> <C>
- ---------------- (Please check the appropriate box(es) below.)
| 1 | [Checkbox] Individual [Checkbox]| Joint Tenant [Checkbox] Other
| Account |
| Registration:| -----------------------------------------------------------------------------------------------------------------
- ---------------- Name SOCIAL SECURITY NUMBER OR TAX ID # OF PRIMARY OWNER

-----------------------------------------------------------------------------------------------------------------
NAME OF MINOR (ONLY ONE PERMITTED)

-----------------------------------------------------------------------------------------------------------------
MINOR'S SOCIAL SECURITY NUMBER AND DATE OF BIRTH

-----------------------------------------------------------------------------------------------------------------
TAXPAYER IDENTIFICATION NUMBER

-----------------------------------------------------------------------------------------------------------------
DAY PHONE NUMBER EVENING PHONE NUMBER

- ---------------- Minimum initial investment of $2,500 Amount of investment $_______
| 3 |
| Investment | Make the check payable to Boston Partners Large Cap Value Fund.
| Information: |
- ---------------- Shareholders may not purchase shares of this Fund with a check issued by a third party and endorsed over to
the Fund.

- ----------------
SYSTEMATIC To select this portion please fill out the information below:
WITHDRAWAL
PLAN: Amount ______________________________________________________ Startup Month _________________________
- ----------------

Frequency Options: Annually [Checkbox] Monthly [Checkbox] Quarterly [Checkbox]

-A minimum account value of $10,000 in a single account is required to establish a Systematic Withdrawal Plan
-Payments will be made on or near the 25th of the month
Please check one of the following options: ________ Please mail checks to Address of Record (Named in
Section 2)
________ Please electronically credit my Bank of Record
(Named in Section 5)

Please check one of the following options: ________ Please mail checks to Address of Record (Named in
Section 2)
________ Please electronically credit my Bank of Record
(Named in Section 5)
</TABLE>

<PAGE>

<S> <C>
- ---------------- To use this option, you must initial the appropriate line below.
| 4 | I authorize the Transfer Agent to accept instructions from any persons to redeem or exchange shares in my
| Telephone | account(s) by telephone in accordance with the procedures and conditions set forth in the Fund's current
| Exchange and | prospectus.
| Redemption: |
- ----------------
------------------------------- ----------------------------- Redeem shares, and send the proceeds to
Individual initial joint initial the address of record.

Exchange shares for shares of the Boston
------------------------------- ----------------------------- Partners Mid Cap Value Fund or Boston
Individual initial joint initial Partners Bond Fund.

- ---------------- The Automatic Investment Plan, which is available to shareholders of the Fund, makes possible regularly
| 5 | scheduled purchases of Fund shares to allow dollar-cost averaging. The Fund's Transfer Agent can arrange for
| Automatic | an amount of money selected by you to be deducted from your checking account and used to purchase shares of
| Investment | the Fund.
| Plan: | Please debit $________ from my checking account (named below) on or about the 20th of the month.
- ---------------- Please attach an unsigned, voided check.

[Checkbox] Monthly [Checkbox] Every Alternate Month [Checkbox] Quarterly [Checkbox] Other

-----------------------------------------------------------------------------------------------------------------
BANK ABA NUMBER BANK ACCOUNT NUMBER

- ---------------- The undersigned warrants that I (we) have full authority and, if a natural person, I (we) am (are) of legal age
| 6 | to purchase shares pursuant to this Account Application, and I (we) have received a current prospectus
| | for the Fund in which I (we) am (are) investing.
| Signatures: | Under the Interest and Dividend Tax Compliance Act of 1983, the Fund is required to have the following
- ---------------- certification:
Under penalties of perjury, I certify that:
(1) The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to
be issued to me), and
(2) I am not subject to backup withholding because (a) I am exempt from backup withholding, or (b) I have not
been notified by the Internal Revenue Service that I am subject to 31% backup withholding as a result of a
failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup
withholding.

NOTE: YOU MUST CROSS OUT ITEM (2) IF YOU HAVE BEEN NOTIFIED BY THE IRS THAT YOU ARE CURRENTLY SUBJECT TO BACKUP
WITHHOLDING BECAUSE YOU HAVE FAILED TO REPORT ALL INTEREST AND DIVIDENDS ON YOUR TAX RETURN. THE INTERNAL REVENUE
SERVICE DOES NOT REQUIRE YOUR CONSENT TO ANY PROVISION OF THIS DOCUMENT OTHER THAN THE CERTIFICATION REQUIRED TO
AUDIT BACKUP WITHHOLDING.

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF APPLICANT DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF JOINT OWNER DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

For information on additional options, such as IRA Applications, rollover requests for qualified retirement
plans, or for wire instructions, please call us at 1-888-261-4073.

MAIL COMPLETED ACCOUNT APPLICATION AND CHECK TO: THE BOSTON PARTNERS LARGE CAP VALUE FUND
C/O PFPC INC.
P.O. BOX 8852
WILMINGTON, DE 19899-8852

</TABLE>

<PAGE>
BOSTON PARTNERS MID CAP VALUE FUND
(INSTITUTIONAL SHARES)
OF
THE RBB FUND, INC.

Boston Partners Mid Cap Value Fund (the "Fund") is an investment portfolio
of The RBB Fund, Inc. ("RBB"), an open-end management investment company. The
shares of the Institutional Class ("Shares") offered by this Prospectus
represent interests in the Fund. The Fund is a diversified fund that seeks
long-term growth of capital, with current income as a secondary objective,
primarily through equity investments, such as common stocks. It seeks to achieve
its objectives by investing at least 65% of its total assets in a diversified
portfolio consisting of equity securities of issuers with a market
capitalization of primarily between $200 million and $4 billion, and identified
by Boston Partners Asset Management, L.P. (the "Adviser") as equity securities
that possess value characteristics. The Adviser examines various factors in
determining the value characteristics of such issuers, including, but not
limited to, price to book value ratios and price to earnings ratios. These value
characteristics are examined in the context of the issuer's operating and
financial fundamentals such as return on equity, earnings growth and cash flow.

PROSPECTUS DECEMBER 1, 1997
(as revised May 29, 1998)

<PAGE>

EXPENSE TABLE

The following table illustrates annual operating expenses as a percentage
of average daily net assets incurred by Institutional Shares of the Fund (after
fee waivers and expense reimbursements) during the period ended August 31, 1997,
restated to reflect the expenses that the Fund expects to incur during the
current fiscal year with respect to its Institutional Shares. An example based
on the summary is also shown.

ANNUAL FUND OPERATING EXPENSES (AS A PERCENTAGE OF AVERAGE NET ASSETS)

Management Fees (after waivers)*.........................0.01%
12b-1 Fees ..............................................0.00%
Other Expenses (after waivers and
expense reimbursements)*........................0.99%
Total Fund Operating Expenses (after waivers and
expense reimbursements)*........................1.00%
=====
* In the absence of fee waivers and expense reimbursements, Management
Fees would be 0.80%; Other Expenses would be 11.47%; and Total Fund
Operating Expenses would be 12.27%. Management Fees are based on
average daily net assets and are calculated daily and paid monthly.

EXAMPLE

An investor would pay the following expenses on a $1,000 investment in
the Fund, assuming (1) a 5% annual return and (2) redemption at the end of each
time period:

ONE THREE FIVE TEN
YEAR YEARS YEARS YEARS
---- ----- ----- -----
Boston Partners Mid Cap Value Fund $10 $32 $55 $122

The Fee Table is designed to assist an investor in understanding the
various costs and expenses that an investor in the Fund will bear directly or
indirectly. (For more complete descriptions of the various costs and expenses,
see "Management" below.) The Fee Table reflects expense reimbursements and
voluntary waivers of Management Fees and Other Expenses for the Fund, which are
expected to be in effect during the current fiscal year. However, the Adviser
and the Fund's other service providers are under no obligation with respect to
such expense reimbursements and waivers and there can be no assurance that any
future expense reimbursements and waivers of Management Fees or Other Expenses
will not vary from the figures reflected in the Fee Table.

FINANCIAL HIGHLIGHTS
- --------------------------------------------------------------------------------

The "Financial Highlights" presented below set forth certain investment
results for shares of the Institutional Class of the Fund for the period
indicated. Shares of the Institutional Class were first issued on June 2, 1997.
The financial data included in this table should be read in conjunction with the
financial statements and notes thereto and the unqualified report of the
independent accountants thereon, which are incorporated by reference into the
Statement of Additional Information. Further information about the performance
of the Institutional Class of the Fund is available in the Annual Report to
Shareholders. Both the Statement of Additional Information and the Annual Report
to Shareholders may be obtained from the Fund free of charge by calling the
telephone number on page 1 of the prospectus.

-2-

<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND
(FOR AN INSTITUTIONAL SHARE OUTSTANDING THROUGHOUT EACH PERIOD)

For the Period
June 2, 1997*
through
AUGUST 31, 1997
---------------

PER SHARE OPERATING PERFORMANCE**
NET ASSET VALUE, BEGINNING OF PERIOD..................... $ 10.00
------

Net investment income (1)................................ 0.01
Net realized and unrealized gain on
investments(2)........................................... 1.00
-----

Net increase in net assets resulting
from operations.......................................... 1.01

NET ASSET VALUE, END OF PERIOD........................... $ 11.01
=======

Total investment return(3)............................... 10.10%

RATIOS/SUPPLEMENTAL DATA
Net assets, end of period (000).......................... $3,750

Ratio of expenses to average net
assets***(1)(4)........................................ 1.00%
Ratio of net investment income to
average net assets***(1)............................... 1.08%
PORTFOLIO TURNOVER RATE****.............................. 21.80%
Average commission rate per share(5)..................... $0.0348

- -----------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
period, except for dividends and distributions, if any, which are based on
actual shares outstanding on the dates of distributions.
*** Annualized.
**** Not annualized.
(1) Reflects waivers and reimbursements.
(2) The amount shown for a share outstanding throughout the period is not in
accord with the change in the aggregate gains and losses in investments
during the period because of the timing of sales and repurchases of Fund
shares in relation to fluctuating net asset value during the period.
(3) Total return is calculated assuming a purchase of shares on the first day
and a sale of shares on the last day of the period reported and will
include reinvestments of dividends and distributions, if any. Total return
is not annualized.

(4) Without the waiver of advisory, administration and transfer agent fees and
without the reimbursement of certain operating expenses, the ratio of
expenses to average net assets annualized for the period ended August 31,
1997 would have been 12.27% for the Institutional Class.

(5) Computed by dividing the total amount of commissions paid by the total
number of shares purchased and sold during the period subject to such
commissions.

-3-

<PAGE>

INTRODUCTION
- --------------------------------------------------------------------------------

RBB is an open-end management investment company incorporated under the
laws of the State of Maryland currently operating or proposing to operate
twenty-six separate investment portfolios. The Shares offered by this Prospectus
represents an interest in the Boston Partners Mid Cap Value Fund. RBB was
incorporated in Maryland on February 29, 1988.

INVESTMENT OBJECTIVES AND POLICIES
- --------------------------------------------------------------------------------

The Fund's investment objective is to provide long-term growth of capital
with current income as a secondary objective. The Fund seeks to achieve its
objective by investing, under normal market conditions, at least 65% of its
total assets in a diversified portfolio consisting primarily of equity
securities such as common stocks of issuers with a market capitalization of
between $200 million and $4 billion and identified by the Adviser as equity
securities that possess value characteristics.

The Adviser selects securities for the Fund based on a continuous study of
trends in industries and companies, earning power and growth and other
investment criteria. In general, the Fund's investments are broadly diversified
over a number of industries and, as a matter of policy, the Fund will not invest
25% or more of its total assets in any one industry.

The Fund may invest up to 20% of its total assets in securities of foreign
issuers. Investing in securities of foreign issuers involves considerations not
typically associated with investing in securities of companies organized and
operating in the United States. Foreign securities generally are denominated and
pay dividends or interest in foreign currencies. The Fund may hold from time to
time various foreign currencies pending their investment in foreign securities
or their conversion into U.S. dollars. The value of the assets of the Fund as
measured in U.S. dollars may therefore be affected favorably or unfavorably by
changes in exchange rates. There may be less publicly available information
concerning foreign issuers than is available with respect to U.S. issuers.
Foreign securities may not be registered with the U.S. Securities and Exchange
Commission, and generally, foreign companies are not subject to uniform
accounting, auditing and financial reporting requirements comparable to those
applicable to U.S. issuers. See "Investment Objectives and Policies--Foreign
Securities" in the Statement of Additional Information.

The Fund may invest the remainder of its total assets in equity securities
of issuers with lower or higher capitalizations; derivative securities; debt
securities issued by U.S. banks, corporations and other business organizations
that are investment grade securities; and debt securities issued by the U.S.
government or government agencies.

In accordance with the above-mentioned policies, the Fund may also invest
in indexed securities, repurchase agreements, reverse repurchase agreements,
dollar rolls, financial futures contracts, options on futures contracts and may
lend portfolio securities. See "Investment Objectives and Policies" in the
Statement of Additional Information.

The Fund may invest in registered investment companies and investment funds
in foreign countries subject to the provisions of the Investment Company Act of
1940, as amended (the "1940 Act"), and as discussed in "Investment Objectives
and Policies" in the Statement of Additional Information. If the Fund invests in
such investment companies, the Fund will bear its proportionate share of the
costs incurred by such companies, including investment advisory fees.

-4-

<PAGE>

eligible U.S. dollar-denominated money market instruments. The Adviser would
determine when market conditions warrant temporary defensive measures.

INVESTMENT LIMITATIONS
- --------------------------------------------------------------------------------

The Fund may not:

1. Purchase the securities of any one issuer, other than securities issued
or guaranteed by the U.S. Government or its agencies or instrumentalities, if
immediately after and as a result of such purchase more than 5% of the value of
the Fund's total assets would be invested in the securities of such issuer, or
more than 10% of the outstanding voting securities of such issuer would be owned
by the Fund, except that up to 25% of the value of the Fund's total assets may
be invested without regard to such limitations.

2. Purchase any securities which would cause, at the time of purchase, 25%
or more of the value of the total assets of the Fund to be invested in the
obligations of issuers in any single industry, provided that there is no
limitation with respect to investments in U.S. Government obligations.

3. Borrow money or issue senior securities, except that the Fund may borrow
from banks and enter into reverse repurchase agreements and dollar rolls for
temporary purposes in amounts up to one-third of the value of its total assets
at the time of such borrowing; or mortgage, pledge or hypothecate any assets,
except in connection with any such borrowing and then in amounts not in excess
of one-third of the value of the Fund's total assets at the time of such
borrowing. The Fund will not purchase securities while its aggregate borrowings
(including reverse repurchase agreements, dollar rolls and borrowings from
banks) are in excess of 5% of its total assets. Securities held in escrow or
separate accounts in connection with the Fund's investment practices are not
considered to be borrowings or deemed to be pledged for purposes of this
limitation.

PORTFOLIO TURNOVER

The Fund retains the right to sell securities irrespective of how long they
have been held. The Adviser estimates that the annual turnover in the Fund will
not exceed 150%. Such a relatively high portfolio turnover will be accompanied
by relatively high transactional (i.e., brokerage) costs. It may also result in
increased capital gains realized by the Fund and distributed to shareholders.

RISK FACTORS
- --------------------------------------------------------------------------------

As with other mutual funds, there can be no assurance that the Fund will
achieve its objective. The net asset value per share of Shares representing an
interest in the Fund will fluctuate as the values of its portfolio securities
change in response to changing conditions in the equity market. An investment in
the Fund is not intended to constitute a balanced investment program. Other risk
factors are discussed above under "Investment Objectives and Policies" and in
the Statement of Additional Information under "Investment Objectives and
Policies."

-5-

<PAGE>

MANAGEMENT
- --------------------------------------------------------------------------------

BOARD OF DIRECTORS

The business and affairs of RBB and the Fund are managed under the
direction of RBB's Board of Directors.

INVESTMENT ADVISER

Subject to the supervision and direction of the Trust's Board of Trustees,
the Adviser manages the Fund's portfolio in accordance with the Fund's
investment objective and policies, makes investment decisions for the Fund,
places orders to purchase and sell securities, and employs professional
portfolio managers and securities analysts who provide research services to the
Fund. For its services to the Fund, the Adviser is paid a monthly advisory fee
computed at an annual rate of 0.80% of the Fund's average daily net assets. The
Adviser has notified RBB, however, that it intends to waive advisory fees in
excess of .70% during the current fiscal year.

PORTFOLIO MANAGEMENT

The day-to-day portfolio management of the Fund is the responsibility of
Wayne J. Archambo who is senior portfolio manager of the Adviser and a member of
the Adviser's Equity Strategy Committee. Mr. Archambo oversees the investment
activities of the Advisers' $300 million of mid-capitalization value and $900
million of small cap value institutional equity assets under management. Prior
to joining the Adviser in April 1995, Mr. Archambo was employed by The Boston
Company Asset Management from 1989 through April 1995 where he was a senior
portfolio manager and a member of the firm's Equity Policy Committee. Mr.
Archambo has over 15 years of investment experience and is a Chartered Financial
Analyst.

ADMINISTRATOR

PFPC Inc. ("PFPC") serves as administrator to the Fund and generally
assists the Fund in all aspects of its administration and operations, including
matters relating to the maintenance of financial records and accounting. For its
services, PFPC receives a fee calculated at an annual rate of .125% of the
Fund's average daily net assets, with a minimum annual fee of $75,000 payable
monthly on a pro rata basis. PFPC has notified the Fund that it intends to waive
one-half of its minimum annual fee during the current fiscal year.

TRANSFER AGENT, DIVIDEND DISBURSING AGENT, AND CUSTODIAN

DISTRIBUTOR

Provident Distributors, Inc. (the "Distributor" or "PDI), with a principal
business address at Four Falls Corporate Center, 6th Floor, West Conshohocken,
Pennsylvania 19428, acts as distributor for the Shares pursuant to a
distribution agreement (the "Distribution Agreement") with RBB on behalf of the
Shares.

-6-

<PAGE>

ADMINISTRATIVE SERVICES AGENT

EXPENSES

The expenses of the Fund are deducted from its total income before
dividends are paid. Any general expenses of RBB that are not readily
identifiable as belonging to a particular investment portfolio of RBB will be
allocated among all investment portfolios of RBB based upon the relative net
assets of the investment portfolios. The Institutional Class of the Fund may pay
a different share than the Investor Class of other expenses (excluding advisory
and custodial fees) if those expenses are actually incurred in a different
amount by the Institutional Class or if it receives different services.

HOW TO PURCHASE SHARES
- --------------------------------------------------------------------------------

GENERAL

Shares representing an interest in the Fund are offered continuously for
sale by the Distributor. Shares may be purchased initially by completing the
application included in this Prospectus and forwarding the application to the
Fund's transfer agent, PFPC. Purchases of Shares may be effected by wire to an
account to be specified by PFPC or by mailing a check or Federal Reserve Draft,
payable to the order of "The Boston Partners Mid Cap Value Fund," c/o PFPC Inc.,
P.O. Box 8852, Wilmington, Delaware 19899-8852. The name of the Fund, Boston
Partners Mid Cap Value Fund, must also appear on the check or Federal Reserve
Draft. Shareholders may not purchase shares of the Boston Partners Mid Cap Value
Fund with a check issued by a third party and endorsed over to the Fund. Federal
Reserve Drafts are available at national banks or any state bank which is a
member of the Federal Reserve System. Initial investments in the Fund must be at
least $100,000 and subsequent investments must be at least $5,000. For purposes
of meeting the minimum initial purchase, clients which are part of endowments,
foundation or other related groups may be aggregated. The Fund reserves the
right to suspend the offering of Shares for a period of time or to reject any
purchase order.

Shares may be purchased on any Business Day. A "Business Day" is any day
that the New York Stock Exchange, Inc. (the "NYSE") is open for business.
Currently, the NYSE is closed on weekends and New Year's Day, Dr. Martin Luther
King, Jr. Day, Presidents' Day, Good Friday, Memorial Day, Independence Day,
Labor Day, Thanksgiving Day and Christmas Day and on the preceding Friday or
subsequent Monday when one of these holidays falls on a Saturday or Sunday.

The price paid for Shares purchased is based on the net asset value next
computed after a purchase order is received in good order by the Fund or its
agents. Orders received by the Fund or its agents prior to the close of the NYSE
(generally 4:00 p.m. Eastern Time) are priced at that Business Day's net asset
value. Orders received by the Fund or its agents after its close of the NYSE are
priced at the net asset value next determined on the following Business Day. In
those cases where an investor pays for Shares by check, the purchase will be
effected at the net asset value next determined after the Fund or its agents
receives the order and the completed application.

-7-

<PAGE>

A. Telephone the Fund's transfer agent, PFPC, toll-free (888) 261-4073, and
provide PFPC with your name, address, telephone number, Social Security or Tax
Identification Number, the Fund selected, the amount being wired, and by which
bank. PFPC will then provide an investor with a Fund account number. Investors
with existing accounts should also notify PFPC prior to wiring funds.

B. Instruct your bank or broker to wire the specified amount, together with
your assigned account number, to PFPC's account with PNC:

PNC Bank, N.A.
Philadelphia, PA 19103
ABA NUMBER: 0310-0005-3
CREDITING ACCOUNT NUMBER: 86-1108-2507
FROM: (name of investor)
ACCOUNT NUMBER: (Investor's account number
with the Fund)
FOR PURCHASE OF: (name of the Fund)
AMOUNT: (amount to be invested)

C. Fully complete and sign the application and mail it to the address shown
thereon. PFPC will not process purchases until it receives a fully completed and
signed application.

For subsequent investments, an investor should follow steps A and B above.

AUTOMATIC INVESTING

HOW TO REDEEM AND EXCHANGE SHARES
- --------------------------------------------------------------------------------

REDEMPTION BY MAIL

Shareholders may redeem for cash some or all of their Shares of the Fund at
any time. To do so, a written request in proper form must be sent directly to
Boston Partners Mid Cap Value Fund, c/o PFPC Inc., P.O. Box 8852, Wilmington,
Delaware 19899-8852. There is no charge for a redemption.

-8-

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)
<PAGE>

INVOLUNTARY REDEMPTION

PAYMENT OF REDEMPTION PROCEEDS

In all cases, the redemption price is the net asset value per share next
determined after the request for redemption is received in proper form by the
Fund or its agents. Payment for Shares redeemed is made by check mailed within
seven days after acceptance by the Fund or its agents of the request and any
other necessary documents in proper order. Such payment may be postponed or the
right of redemption suspended as provided by the 1940 Act. If the Shares to be
redeemed have been recently purchased by check, the Fund's transfer agent may
delay mailing a redemption check, which may be a period of up to 15 days,
pending a determination that the check has cleared. The Fund has elected to be
governed by Rule 18f-1 under the 1940 Act so that a portfolio is obligated to
redeem its shares solely in cash up to the lesser of $250,000 or 1% of its net
asset value during any 90-day period for any one shareholder of a portfolio.

EXCHANGE PRIVILEGE

The exchange privilege is available to shareholders residing in any state
in which the Shares being acquired may be legally sold. A shareholder may
exchange Shares of the Fund for Institutional Shares of the Boston Partners
Large Cap Value Fund or Boston Partners Bond Fund, subject to restrictions
described under "Exchange Privilege Limitations" below. Such exchange will be
effected at the net asset value of the exchanged Fund and the net asset value of
the Boston Partners Large Cap Value Fund or Boston Partners Bond Fund next
determined after PFPC's receipt of a request for an exchange. An exchange of
Shares will be treated as a sale for federal income tax purposes. See "Taxes." A
shareholder wishing to make an exchange may do so by sending a written request
to PFPC.

If the exchanging shareholder does not currently own Institutional Shares
of the Boston Partners Large Cap Value Fund or Boston Partners Bond Fund, a new
account will be established with the same registration, dividend and capital
gain options as the account from which shares are exchanged, unless otherwise
specified in writing by the shareholder with all signatures guaranteed. A
signature guarantee may be obtained from a domestic bank or trust company,
broker, dealer, clearing agency or savings association who are participants in a
medallion program recognized by the Securities Transfer Association. The three
recognized medallion programs are Securities Transfer Agents Medallion Program
(STAMP), Stock Exchanges Medallion Program (SEMP) and New York Stock Exchange,
Inc. Medallion Signature Program (MSP). Signature guarantees that are not part
of these programs will not be accepted. The exchange privilege may be modified
or terminated at any time, or from time to time, by RBB, upon 60 days' written
notice to shareholders.

If an exchange is to a new account in the Boston Partners Large Cap Value
Fund or Boston Partners Bond Fund, the dollar value of Institutional Shares
acquired must equal or exceed that Fund's minimum for a new account; if to an
existing account, the dollar value must equal or exceed that Fund's minimum for
subsequent investments. If any amount remains in the Fund from which the
exchange is being made, such amount must not drop below the minimum account
value required by the Fund.

EXCHANGE PRIVILEGE LIMITATIONS

The Fund's exchange privilege is not intended to afford shareholders a way
to speculate on short-term movements in the market. Accordingly, in order to
prevent excessive use of the exchange privilege that may potentially disrupt the
management of the Fund and increase transactions costs, the Fund has established
a policy of limiting excessive exchange activity.

-9-
<PAGE>

Shareholders are entitled to six (6) exchange redemptions (at least 30 days
apart) from the Fund during any twelve-month period. Notwithstanding these
limitations, the Fund reserves the right to reject any purchase request
(including exchange purchases from the Boston Partners Large Cap Value Fund and
Boston Partners Bond Fund) that is deemed to be disruptive to efficient
portfolio management.

TELEPHONE TRANSACTIONS

In order to request a telephone exchange or redemption, a shareholder must
have completed and returned an account application containing a telephone
election. To add a telephone option to an existing account that previously did
not provide for this option, a Telephone Authorization Form must be filed with
PFPC. This form is available from PFPC. Once this election has been made, the
shareholder may simply contact PFPC by telephone to request the exchange or
redemption by calling (888) 261-4073. Neither RBB, the Fund, the Distributor,
the Administrator nor any other Fund agent will be liable for any loss,
liability, cost or expense for following RBB's telephone transaction procedures
described below or for following instructions communicated by telephone that
they reasonably believe to be genuine.

RBB's telephone transaction procedures include the following measures: (1)
requiring the appropriate telephone transaction privilege forms; (2) requiring
the caller to provide the names of the account owners, the account social
security number and name of the Fund, all of which must match RBB's records; (3)
requiring RBB's service representative to complete a telephone transaction form,
listing all of the above caller identification information; (4) permitting
exchanges only if the two account registrations are identical; (5) requiring
that redemption proceeds be sent only by check to the account owners of record
at the address of record, or by wire only to the owners of record at the bank
account of record; (6) sending a written confirmation for each telephone
transaction to the owners of record at the address of record within five (5)
Business Days of the call; and (7) maintaining tapes of telephone transactions
for six months, if the fund elects to record shareholder telephone transactions.
For accounts held of record by broker-dealers (other than the Distributor),
financial institutions, securities dealers, financial planners and other
industry professionals, additional documentation or information regarding the
scope of a caller's authority is required. Finally, for telephone transactions
in accounts held jointly, additional information regarding other account holders
is required. Telephone transactions will not be permitted in connection with IRA
or other retirement plan accounts or by an attorney-in-fact under a power of
attorney.

NET ASSET VALUE
- --------------------------------------------------------------------------------

The net asset values for each class of a fund are calculated by adding the
value of the proportionate interest of the class in a fund's cash, securities
and other assets, deducting actual and accrued liabilities of the class and
dividing the result by the number of outstanding shares of the class. The net
asset value of each class are calculated independently of each other class. The
net asset values are calculated as of the close of regular trading on the NYSE,
generally 4:00 p.m. Eastern Time on each Business Day.

Valuation of securities held by the Fund is as follows: securities traded
on a national securities exchange or on the NASDAQ National Market System are
valued at the last reported sale price that day; securities traded on a national
securities exchange or on the NASDAQ National Market System for which there were
no sales on that day and securities traded on other over-the-counter markets for
which market quotations are readily available are valued at the mean of the bid
and asked prices; and securities for which market quotations are not readily
available are valued at fair market value as determined in good faith by or
under the direction of the RBB's Board of Directors. The amortized cost method
of valuation may also be used with respect to debt obligations with sixty days
or less remaining to maturity.

-10-

<PAGE>

DIVIDENDS AND DISTRIBUTIONS
- --------------------------------------------------------------------------------

The Fund will distribute substantially all of the net investment income and
net realized capital gains, if any, of the Fund to the Fund's shareholders. All
distributions are reinvested in the form of additional full and fractional
Shares unless a shareholder elects otherwise.

TAXES
- --------------------------------------------------------------------------------

Distributions out of the "net capital gain" (the excess of net long-term
capital gain over net short-term capital loss), if any, of the Fund, and out of
the portion of such net capital gain that constitutes mid-term capital gain,
will be taxed to shareholders as long-term capital gain or mid-term capital
gain, as the case may be, regardless of the length of time a shareholder has
held his Shares, whether such gain was reflected in the price paid for the
Shares, or whether such gain was attributable to bonds bearing tax-exempt
interest. All other distributions, to the extent they are taxable, are taxed to
shareholders as ordinary income.

Shareholders who exchange shares representing interests in one Fund for
shares representing interests in another Fund will generally recognize capital
gain or loss for federal income tax purposes.

Shareholders who are nonresident alien individuals, foreign trusts or
estates, foreign corporations or foreign partnerships may be subject to
different U.S. Federal income tax treatment.

-11-

<PAGE>

MULTI-CLASS STRUCTURE
- --------------------------------------------------------------------------------

The Fund offers one other class of shares, Investor Shares, which are
offered directly to individual investors pursuant to a separate prospectus.
Shares of each class represent equal pro rata interests in the Fund and accrue
dividends and calculate net asset value and performance quotations in the same
manner. The Fund will quote performance of the Investor Shares separately from
Institutional Shares. Because of different expenses paid by the Institutional
Shares, the total return on such shares can be expected, at any time, to be
different than the total return on Investor Shares. Information concerning these
other classes may be obtained by calling the Fund at (888) 261-4073.

DESCRIPTION OF SHARES
- --------------------------------------------------------------------------------

THIS PROSPECTUS AND THE STATEMENT OF ADDITIONAL INFORMATION INCORPORATED
HEREIN RELATE PRIMARILY TO BOSTON PARTNERS MID CAP VALUE FUND AND DESCRIBE ONLY
THE INVESTMENT OBJECTIVE AND POLICIES, OPERATIONS, CONTRACTS AND OTHER MATTERS
RELATING TO BOSTON PARTNERS MID CAP VALUE FUND.

RBB currently does not intend to hold annual meetings of shareholders
except as required by the 1940 Act or other applicable law. The law under
certain circumstances provides shareholders with the right to call for a meeting
of shareholders to consider the removal of one or more directors. To the extent
required by law, RBB will assist in shareholder communication in such matters.

Holders of Shares of the Fund will vote in the aggregate and not by class
on all matters, except where otherwise required by law. Further, shareholders of
all investment portfolios of RBB will vote in the aggregate and not by portfolio
except as otherwise required by law or when the Board of Directors determines
that the matter to be voted upon affects only the interests of the shareholders
of a particular investment portfolio. (See the Statement of Additional
Information under "Additional Information Concerning Fund Shares" for examples
when the 1940 Act requires voting by investment portfolio or by class.)
Shareholders of the Fund are entitled to one vote for each full share held
(irrespective of class or portfolio) and fractional votes for fractional shares
held. Voting rights are not cumulative and, accordingly, the holders of more
than 50% of the aggregate shares of Common Stock of the Fund may elect all of
the directors.

As of November 15, 1997, to the Fund's knowledge, no person held of record
or beneficially 25% or more of the outstanding shares of all classes of RBB.

-12-

<PAGE>

OTHER INFORMATION
- --------------------------------------------------------------------------------

REPORTS AND INQUIRIES

Shareholders will receive unaudited semi-annual reports describing the
Fund's investment operations and annual financial statements audited by
independent accountants. Shareholder inquiries should be addressed to PFPC Inc.,
the Fund's transfer agent, Bellevue Park Corporate Center, 400 Bellevue Parkway,
Wilmington, Delaware 19809, toll-free (888) 261-4073.

SHARE CERTIFICATES

In the interest of economy and convenience, physical certificates
representing Shares in the Fund are not normally issued.

HISTORICAL PERFORMANCE INFORMATION

For the period from commencement of operations (June 2, 1997) through
August 31, 1997, the total return (not annualized) for the Institutional Class
of Shares of the Fund was as follows:

Unannualized investment returns for the period ended
August 31, 1997

Since
INCEPTION
---------
Boston Partners Mid Cap Value Fund
(Institutional Shares)............................... 10.10%

The total return assumes the reinvestment of all dividends and capital
gains and reflects expense reimbursements and investment advisory fee waivers in
effect. Without these expense reimbursements and waivers, the Fund's performance
would have been lower. Of course, past performance is no guarantee of future
results. Investment return and principal value will fluctuate, so that Shares,
when redeemed, may be worth more or less than the original cost. For more
information on performance, see "Performance Information" in the Statement of
Additional Information.

-13-

<PAGE>

The table below presents the Composite performance history of certain of
the Adviser's managed accounts on an annualized basis for the period ended
August 31, 1997. The Composite is comprised of the Adviser's institutional
accounts and other privately managed accounts with investment objectives,
policies and strategies substantially similar to those of the Fund, although the
accounts have longer operating histories than the Fund, which commenced
operations on June 2, 1997. The Composite performance information includes the
reinvestment of dividends received in the underlying securities and includes
payment of investment advisory fees. The privately managed accounts in the
Composite are only available to the Adviser's institutional advisory clients.
The past performance of the accounts which comprise the Composite is not
indicative of the future performance of the Fund. These accounts have lower
investment advisory fees than the Fund and the Composite performance figures
would have been lower if subject to the higher fees and expenses to be incurred
by the Fund. These private accounts are not subject to the same investment
limitations, diversification requirements and other restrictions which are
imposed upon mutual funds under the 1940 Act and the Internal Revenue Code,
which, if imposed, may have adversely affected the performance results of the
Composite. Listed below the performance history for the Composite is a
comparative index comprised of securities similar to those in which accounts
contained in the Composite are invested.

Annualized investment returns for the period ended August 31, 1997

SINCE
ONE YEAR INCEPTION
-------- ---------

Composite Performance 51.0% 37.8%*
Russell 2500 Index 31.5% 25.9%

* The Adviser commenced managing these accounts on May 1, 1995.

The Russell 2500 Index represents the largest 3,000 companies domiciled in
the United States minus the largest 500 companies as determined by the market
value of such companies.

FUTURE PERFORMANCE INFORMATION

From time to time, the Fund may advertise its performance, including
comparisons to other mutual funds with similar investment objectives and to
stock or other relevant indices. All such advertisements will show the average
annual total return over one, five and ten year periods or, if such periods have
not yet elapsed, shorter periods corresponding to the life of the Fund. Such
total return quotations will be computed by finding the compounded average
annual total return for each time period that would equate the assumed initial
investment of $1,000 to the ending redeemable value, net of fees, according to a
required standardized calculation. The standard calculation is required by the
SEC to provide consistency and comparability in investment company advertising.
The Fund may also from time to time include in such advertising an aggregate
total return figure or a total return figure that is not calculated according to
the standardized formula in order to compare more accurately the Fund's
performance with other measures of investment return. For example, the Fund's
total return may be compared with data published by Lipper Analytical Services,
Inc., CDA Investment Technologies, Inc. or Weisenberger Investment Company
Service, or with the performance of the Russell 2500 Index. Performance
information may also include evaluation of the Fund by nationally recognized
ranking services and information as reported in financial publications such as
BUSINESS WEEK, FORTUNE, INSTITUTIONAL INVESTOR, MONEY MAGAZINE, FORBES,
BARRON'S, THE WALL STREET JOURNAL, THE NEW YORK TIMES, or other national,
regional or local publications. All advertisements containing performance data
will include a legend disclosing that such performance data represents past
performance and that the investment return and principal value of an investment
will fluctuate so that an investor's Shares, when redeemed, may be worth more or
less than their original cost.

-14-

<PAGE>

[THIS PAGE INTENTIONALLY LEFT BLANK]

-15-

<PAGE>

NO PERSON HAS BEEN AUTHORIZED TO GIVE ANY
INFORMATION OR MAKE ANY REPRESENTATIONS NOT
CONTAINED IN THIS PROSPECTUS OR IN RBB'S STATEMENT
OF ADDITIONAL INFORMATION INCORPORATED HEREIN BY PROSPECTUS
REFERENCE, IN CONNECTION WITH THE OFFERING MADE BY
THIS PROSPECTUS AND, IF GIVEN OR MADE, SUCH DECEMBER 1, 1997
REPRESENTATIONS MUST NOT BE RELIED UPON AS HAVING (as revised May 29, 1998)
BEEN AUTHORIZED BY RBB OR ITS DISTRIBUTOR. THIS
PROSPECTUS DOES NOT CONSTITUTE AN OFFERING BY RBB
OR BY THE DISTRIBUTOR IN ANY JURISDICTION IN WHICH
SUCH OFFERING MAY NOT LAWFULLY BE MADE.

TABLE OF CONTENTS
PAGE
----

FINANCIAL HIGHLIGHTS.......................... 2
INTRODUCTION.................................. 4
INVESTMENT OBJECTIVES AND POLICIES............ 4
INVESTMENT LIMITATIONS........................ 5
RISK FACTORS.................................. 5
MANAGEMENT.................................... 6
HOW TO PURCHASE SHARES........................ 7 BOSTON PARTNERS
HOW TO REDEEM AND EXCHANGE MID CAP
SHARES............................... 8 VALUE FUND
NET ASSET VALUE............................... 10
DIVIDENDS AND DISTRIBUTIONS................... 11 (Institutional Shares)
TAXES ..................................... 11
MULTI-CLASS STRUCTURE......................... 12
DESCRIPTION OF SHARES......................... 12
OTHER INFORMATION............................. 13

INVESTMENT ADVISER
Boston Partners Asset Management, L.P.
Boston, Massachusetts

CUSTODIAN
PNC Bank, N.A.
Philadelphia, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

ADMINISTRATIVE SERVICES AGENT
Provident Distributors, Inc.
West Conshohocken, Pennsylvania

DISTRIBUTOR
Provident Distributors, Inc.
West Conshohocken, Pennsylvania

COUNSEL bp
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania BOSTON PARTNERS ASSET MANAGEMENT, L.P.
--------------------------------------
INDEPENDENT ACCOUNTANTS
Coopers & Lybrand L.L.P.
Philadelphia, Pennsylvania

(LOGO)
(GRAPHIC OMITTED)

<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND bp
(INSTITUTIONAL CLASS) BOSTON PARTNERS ASSET MANAGEMENT, L.P.
--------------------------------------

ACCOUNT APPLICATION
PLEASE NOTE: Do not use this form to open a retirement plan account. For an IRA application or help with this Application, please
call 1-888-261-4073.

<S> <C>
- ---------------- (Please check the appropriate box(es) below.)
| 1 | [Checkbox] Individual [Checkbox] Joint Tenant [Checkbox] Other
| Account |
| Registration:| ----------------------------------------------------------------------------------------------------------------
- ---------------- Name SOCIAL SECURITY NUMBER OR TAX ID # OF PRIMARY OWNER

----------------------------------------------------------------------------------------------------------------
NAME OF JOINT OWNER JOINT OWNER SOCIAL SECURITY NUMBER OR TAX ID #
For joint accounts,the account registrants will be joint tenants with right of survivorship and not tenants in
common unless tenants in common or community property registrations are requested.

- -------------- UNIFORM GIFTS/TRANSFER TO MINOR'S ACT
GIFT TO MINOR:
- -------------- ----------------------------------------------------------------------------------------------------------------
NAME OF ADULT CUSTODIAN (ONLY ONE PERMITTED)

----------------------------------------------------------------------------------------------------------------
NAME OF MINOR (ONLY ONE PERMITTED)

----------------------------------------------------------------------------------------------------------------
MINOR'S SOCIAL SECURITY NUMBER AND DATE OF BIRTH

- ------------------
CORPORATION,
PARTNERSHIP, TRUST
OR OTHER ENTITY:
- ------------------ ----------------------------------------------------------------------------------------------------------------
NAME OF CORPORATION, PARTNERSHIP, OR OTHER NAME(S) OF TRUSTEE(S)

----------------------------------------------------------------------------------------------------------------
TAXPAYER IDENTIFICATION NUMBER

- ---------------- ----------------------------------------------------------------------------------------------------------------
| 2 | STREET OR P.O. BOX AND/OR APARTMENT NUMBER
| Mailing |
| Address: | ----------------------------------------------------------------------------------------------------------------
- ---------------- CITY STATE ZIP CODE

----------------------------------------------------------------------------------------------------------------
DAY PHONE NUMBER EVENING PHONE NUMBER

- ---------------- Minimum initial investment of $100,000 Amount of investment $____________
| 3 |
| Investment | Make the check payable to Boston Partners Mid Cap Value Fund.
| Information: |
- ---------------- Shareholders may not purchase shares of this Fund with a check issued by a third party and endorsed over
to the Fund.

- ---------------- To use this option, you must initial the appropriate line below. I authorize the Transfer Agent to accept
| 4 | instructions from any persons to redeem or exchange shares in my account(s) by telephone in accordance with the
| Telephone | procedures and conditions set forth in the Fund's current prospectus.
| Redemption: |
- ----------------
-------------------------- --------------------------- Redeem shares, and send the proceeds to the
individual initial joint initial address of record.

-------------------------- --------------------------- Exchange shares for shares of The Boston
individual initial joint initial Partners Large Cap Value Fund or Boston
Partners Bond Fund.

</TABLE>

<PAGE>

<S> <C>

- ---------------- The Automatic Investment Plan, which is available to shareholders of the Fund, makes possible regularly
| 5 | scheduled purchases of Fund shares to allow dollar-cost averaging. The Fund's Transfer Agent can arrange for
| Automatic | an amount of money selected by you to be deducted from your checking account and used to purchase shares of the
| Investment | Fund.
| Plan: |
- ----------------

Please debit $________ from my checking account (named below on or about the 20th of the month. Please attach an
unsigned, voided check.
Monthly [Checkbox] Every Alternate Month [Checkbox] Quarterly [Checkbox] Other [Checkbox]

- --------------- -----------------------------------------------------------------------------------------------------------------
BANK OF RECORD: BANK NAME STREET ADDRESS OR P.O. BOX
- ---------------
-----------------------------------------------------------------------------------------------------------------
CITY STATE ZIP CODE

-----------------------------------------------------------------------------------------------------------------
BANK ABA NUMBER BANK ACCOUNT NUMBER

- ---------------- The undersigned warrants that I (we) have fully authority and, if a natural person, I (we) am (are) of legal age
| 6 | to purchase shares pursuant to this Account Application, and I (we) have received a current prospectus for the
| | Fund in which I (we) am (are) investing.
| Signatures: | Under the Interest and Dividend Tax Compliance Act of 1983, the Fund is required to have the following
- ---------------- certification:
Under penalties of perjury, I certify that:
(1) The number shown on this form is my correct taxpayer identification number (or I am waiting for a
number tobe issued to me), and
(2) I am not subject to backup withholding because (a) I am exempt from backup withholding, or (b) I have not
been notified by the Internal Revenue Service that I am subject to 31% backup withholding as a result of a
failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup
withholding.

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF APPLICANT DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF JOINT OWNER DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

For information on additional options, such as IRA Applications, rollover requests for qualified retirement
plans, or for wire instructions, please call us at 1-888-261-4073.

MAIL COMPLETED ACCOUNT APPLICATION AND CHECK TO: THE BOSTON PARTNERS MID CAP VALUE FUND
C/O PFPC INC.
P.O. BOX 8852
WILMINGTON, DE 19899-8852

</TABLE>

<PAGE>
BOSTON PARTNERS MID CAP VALUE FUND
(INVESTOR CLASS)
OF
THE RBB FUND, INC.

Boston Partners Mid Cap Value Fund (the "Fund") is an investment portfolio
of The RBB Fund, Inc. ("RBB"), an open-end management investment company. The
shares of the Investor Class ("Shares") offered by this Prospectus represent
interests in the Fund. The Fund is a diversified fund that seeks long-term
growth of capital, with current income as a secondary objective, primarily
through equity investments, such as common stocks. It seeks to achieve its
objectives by investing at least 65% of its total assets in a diversified
portfolio consisting of equity securities of issuers with a market
capitalization of primarily between $200 million and $4 billion, and identified
by Boston Partners Asset Management, L.P. (the "Adviser") as equity securities
that possess value characteristics. The Adviser examines various factors in
determining the value characteristics of such issuers, including but not limited
to, price to book value ratios and price to earnings ratios. These value
characteristics are examined in the context of the issuer's operating and
financial fundamentals such as return on equity, earnings growth and cash flow.

This Prospectus contains information that a prospective investor needs to
know before investing. Please keep it for future reference. A Statement of
Additional Information, dated December 1, 1997, has been filed with the
Securities and Exchange Commission and is incorporated by reference in this
Prospectus. It may be obtained free of charge from the Fund by calling (888)
261-4073. The Prospectus and the Statement of Additional Information are
available for reference, along with other related material on the SEC Internet
Web Site (http://www.sec.gov).

- --------------------------------------------------------------------------------

PROSPECTUS December 1, 1997

(as revised May 29, 1998)

<PAGE>

EXPENSE TABLE

The following table illustrates annual operating expenses as a percentage
of average daily net assets incurred by Investor Shares of the Fund (after fee
waivers and expense reimbursements) during the fiscal period ended August 31,
1997, restated to reflect the expenses that the Fund expects to incur during the
current fiscal year with respect to its Investor Shares. An example based on the
summary is also shown.

ANNUAL FUND OPERATING EXPENSES (AS A PERCENTAGE OF AVERAGE NET ASSETS)

Management Fees (after waivers)*......................... 0.01%
12b-1 Fees .............................................. 0.25%
Other Expenses (after waivers and expense
reimbursements)*........................................ 0.99%
-----
Total Fund Operating Expenses (after waivers
and expense reimbursements)*........................... 1.25%
=====

* In the absence of fee waivers and expense reimbursements, Management Fees
would be 0.80%; Other Expenses would be 11.32%; and Total Fund Operating
Expenses would be 12.37%. Management Fees and 12b-1 Fees are each based on
average daily net assets and are calculated daily and paid monthly.

EXAMPLE

An investor would pay the following expenses on a $1,000 investment in the
Fund, assuming (1) a 5% annual return and (2) redemption at the end of each time
period:

ONE THREE FIVE TEN
YEAR YEARS YEARS YEARS
---- ----- ----- -----
Boston Partners Mid Cap Value Fund $13 $40 $69 $151

The Fee Table is designed to assist an investor in understanding the
various costs and expenses that an investor in the Fund will bear directly or
indirectly. (For more complete descriptions of the various costs and expenses,
see "Management" and "Distribution of Shares" below.) The Fee Table reflects
expense reimbursements and voluntary waivers of Management Fees and Other
Expenses for the Fund, which are expected to be in effect during the current
fiscal year. However, the Adviser and the Fund's service providers are under no
obligation with respect to such fee waivers and expense reimbursements and there
can be no assurance that any future expense reimbursements and waivers of
Management Fees or Other Expenses will not vary from the figures reflected in
the Fee Table.

FINANCIAL HIGHLIGHTS
- --------------------------------------------------------------------------------

The "Financial Highlights" presented below set forth certain investment
results for shares of the Investor Class of the Fund for the period indicated.
Shares of the Investor Class were first issued on June 2, 1997. The financial
data included in this table should be read in conjunction with the financial
statements and notes thereto and the unqualified report of the independent
accountants thereon, which are incorporated by reference into the Statement of
Additional Information. Further information about the performance of the
Investor Class of the Fund is available in the Annual Report to Shareholders.
Both the Statement of Additional Information and the Annual Report to
Shareholders may be obtained from the Fund free of charge by calling the
telephone number on page 1 of the prospectus.

-2-

<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND
(FOR AN INVESTOR SHARE OUTSTANDING THROUGHOUT EACH PERIOD)

For the Period June
2, 1997* through
August 31, 1997
---------------
INVESTOR CLASS
--------------

PER SHARE OPERATING PERFORMANCE** $ 10.00
------
NET ASSET VALUE, BEGINNING OF PERIOD..................

Net investment income (1)............................. 0.01
Net realized and unrealized gain on
investments(2)........................................ 1.00
-----

Net increase in net assets resulting
from operations....................................... 1.01

NET ASSET VALUE, END OF PERIOD........................ $ 11.01
======

Total investment return(3)............................ 10.10%

RATIOS/SUPPLEMENTAL DATA
Net assets, end of period (000)....................... $598

Ratio of expenses to average net
assets***(1)(4)..................................... 1.10%
Ratio of net investment income to
average net assets***(1)............................ .61%
PORTFOLIO TURNOVER RATE****........................... 21.80%
Average commission rate per share(5).................. $0.0348

- ----------------------

* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
period, except for dividends and distributions, if any, which are based
on actual shares outstanding on the dates of distributions.
*** Annualized.
**** Not annualized.
(1) Reflects waivers and reimbursements.
(2) The amount shown for a share outstanding throughout the period is not
in accord with the change in the aggregate gains and losses in
investments during the period because of the timing
of sales and repurchases of Fund shares in relation to fluctuating net
asset value during the period.
(3) Total return is calculated assuming a purchase of shares on the first
day and a sale of shares on the last day of the period reported and
will include reinvestments of dividends and distributions, if any.
Total return is not annualized.

(4) Without the waiver of advisory, administration and transfer agent fees
and without the reimbursement of certain operating expenses, the ratio
of expenses to average net assets annualized for the period ended
August 31, 1997 would have been 12.37% for the Investor Class.

(5) Computed by dividing the total amount of commissions paid by the total
number of shares purchased and sold during the period subject to such
commissions.

-3-

<PAGE>

INTRODUCTION
- --------------------------------------------------------------------------------

RBB is an open-end management investment company incorporated under the
laws of the State of Maryland currently operating or proposing to operate
twenty-six separate investment portfolios. The Shares offered by this Prospectus
represents an interest in the Boston Partners Mid Cap Value Fund. RBB was
incorporated in Maryland on February 29, 1988.

INVESTMENT OBJECTIVES AND POLICIES
- --------------------------------------------------------------------------------

The Fund's investment objectives are to provide long-term growth of capital
with current income as a secondary objective. The Fund seeks to achieve its
objectives by investing, under normal market conditions, at least 65% of its
total assets in a diversified portfolio consisting primarily of equity
securities such as common stocks of issuers with a market capitalization of
between $200 million and $4 billion, and identified by the Adviser as equity
securities that possess value characteristics.

The Fund may invest up to 20% of its total assets in securities of foreign
issuers. Investing in securities of foreign issuers involves considerations not
typically associated with investing in securities of companies organized and
operating in the United States. Foreign securities generally are denominated and
pay dividends or interest in foreign currencies. The Fund may hold from time to
time various foreign currencies pending their investment in foreign securities
or their conversion into U.S. dollars. The value of the assets of the Fund as
measured in U.S. dollars may therefore be affected favorably or unfavorably by
changes in exchange rates. There may be less publicly available information
concerning foreign issuers than is available with respect to U.S. issuers.
Foreign securities may not be registered with the U.S. Securities and Exchange
Commission, and generally, foreign companies are not subject to uniform
accounting, auditing and financial reporting requirements comparable to those
applicable to U.S. issuers. See "Investment Objectives and Policies--Foreign
Securities" in the Statement of Additional Information.

-4-

<PAGE>

eligible U.S. dollar-denominated money market instruments. The Adviser will
determine when market conditions warrant temporary defensive measures.

The Fund's investment objectives and the policies described above may be
changed by the RBB's Board of Directors without the affirmative vote of the
holders of a majority of the outstanding Shares representing interests in the
Fund.

INVESTMENT LIMITATIONS
- --------------------------------------------------------------------------------

The Fund may not:

1. Purchase the securities of any one issuer, other than
securities issued or guaranteed by the U.S. Government or its agencies
or instrumentalities, if immediately after and as a result of such
purchase more than 5% of the value of the Fund's total assets would be
invested in the securities of such issuer, or more than 10% of the
outstanding voting securities of such issuer would be owned by the
Fund, except that up to 25% of the value of the Fund's total assets may
be invested without regard to such limitations.

3. Borrow money or issue senior securities, except that the
Fund may borrow from banks and enter into reverse repurchase agreements
and dollar rolls for temporary purposes in amounts up to one-third of
the value of its total assets at the time of such borrowing; or
mortgage, pledge or hypothecate any assets, except in connection with
any such borrowing and then in amounts not in excess of one-third of
the value of the Fund's total assets at the time of such borrowing. The
Fund will not purchase securities while its aggregate borrowings
(including reverse repurchase agreements, dollar rolls and borrowings
from banks) are in excess of 5% of its total assets. Securities held in
escrow or separate accounts in connection with the Fund's investment
practices are not considered to be borrowings or deemed to be pledged
for purposes of this limitation.

PORTFOLIO TURNOVER

RISK FACTORS
- --------------------------------------------------------------------------------

Investment methods described in this Prospectus are among those which the
Fund has the power to utilize. Some may be employed on a regular basis; others
may not be used at all. Accordingly, reference to any particular method or
technique carries no implication that it will be utilized or, if it is, that it
will be successful.

-5-

<PAGE>

MANAGEMENT
- --------------------------------------------------------------------------------

BOARD OF DIRECTORS

The business and affairs of RBB and the Fund are managed under the
direction of RBB's Board of Directors.

INVESTMENT ADVISER

Boston Partners Asset Management, L.P., located at One Financial Center,
43rd Floor, Boston, Massachusetts 02111, serves as the Fund's investment
adviser. The Adviser provides investment management and investment advisory
services to investment companies and other institutional accounts that had
aggregate total assets under management as of September 30, 1997, in excess of
$12.5 billion. Boston Partners' general partner is Boston Partners, Inc., a
company that acts as a general partner for investment advisers organized as
limited partnerships.

Subject to the supervision and direction of RBB's Board of Directors, the
Adviser manages the Fund's portfolio in accordance with the Fund's investment
objectives and policies, makes investment decisions for the Fund, places orders
to purchase and sell securities, and employs professional portfolio managers and
securities analysts who provide research services to the Fund. For its services
to the Fund, the Adviser is paid a monthly advisory fee computed at an annual
rate of 0.80% of the Fund's average daily net assets. The Adviser has notified
RBB, however, that it intends to waive advisory fees in excess of 0.70% of the
Fund's average daily net assets during the current fiscal year.

PORTFOLIO MANAGEMENT

The day-to-day portfolio management of the Fund is the responsibility of
Wayne J. Archambo who is a senior portfolio manager of the Adviser and a member
of the Adviser's Equity Strategy Committee. Mr. Archambo oversees the investment
activities of the Adviser's $300 million of mid-capitalizations value and $900
million of small cap value institutional equity assets under management. Prior
to joining the Adviser in April 1995, Mr. Archambro was employed by The Boston
Company Asset Management from 1989 through April 1995 where he was a senior
portfolio manager and a member of the Firm's Equity Policy Committee. Mr.
Archambro has over 15 years of investment experience and is a Chartered
Financial Analyst.

ADMINISTRATOR

PFPC Inc. ("PFPC") serves as administrator to the Fund and generally
assists the Fund in all aspects of its administration and operations, including
matters relating to the maintenance of financial records and accounting. For its
services, PFPC receives a fee calculated at an annual rate of .125% of the
Fund's average daily net assets with a minimum annual fee of $75,000 payable
monthly on a pro rata basis. PFPC has notified RBB, however, that it intends to
waive one-half of its minimum annual fee during the current fiscal year.

TRANSFER AGENT, DIVIDEND DISBURSING AGENT, AND CUSTODIAN

DISTRIBUTOR

-6-

<PAGE>

EXPENSES

The expenses of the Fund are deducted from its total income before
dividends are paid. Any general expenses of RBB that are not readily
identifiable as belonging to a particular investment portfolio of RBB will be
allocated among all investment portfolios of RBB based upon the relative net
assets of the investment portfolios. The Investor Class of the Fund pays its own
distribution fees, and may pay a different share than the Institutional Class of
other expenses (excluding advisory and custodial fees) if those expenses are
actually incurred in a different amount by the Investor Class or if it receives
different services.

The Adviser may assume expenses of the Fund from time to time. To the
extent any service providers assume expense of the Fund, such assumption of
expenses will have the effect of lowering the Fund's overall expense ratio and
increasing its yield to investors.

DISTRIBUTION OF SHARES
- --------------------------------------------------------------------------------

The Board of Directors of RBB has approved and adopted a Distribution
Agreement and Plan of Distribution for the Shares (the "Plan") pursuant to Rule
12b-1 under the 1940 Act. Under the Plan, the Distributor is entitled to receive
from the Fund a distribution fee with respect to the shares, which is accrued
daily and paid monthly, of up to 0.25% on an annualized basis of the average
daily net assets of the Shares. The actual amount of such compensation under the
Plan is agreed upon by RBB's Board of Directors and by the Distributor in the
Distribution Agreement. The Distributor may, in its discretion, from time to
time waive voluntarily all or any portion of its distribution fee.

The Plan obligates the Fund, during the period it is in effect, to accrue
and pay to the Distributor on behalf of the Shares the fee agreed to under the
Distribution Agreement. Payments under the Plan are not tied exclusively to
expenses actually incurred by the Distributor and the payments may exceed
distribution expenses actually incurred.

PURCHASES THROUGH INTERMEDIARIES

Shares of the Fund may be available through certain brokerage firms,
financial institutions and other industry professionals (collectively, "Service
Organizations"). Certain features of the Shares, such as the initial and
subsequent investment minimums and certain trading restrictions, may be modified
or waived by Service Organizations. Service Organizations may impose transaction
or administrative charges or other direct fees, which charges and fees would not
be imposed if Shares are purchased directly from the Fund. Therefore, a client
or customer should contact the Service Organization acting on his behalf
concerning the fees (if any) charged in connection with a purchase or redemption
of Shares and should read this Prospectus in light of the terms governing his
accounts with the Service Organization. Service Organizations will be
responsible for promptly transmitting client or customer purchase and redemption
orders to the Fund in accordance with their agreements with the Fund and with
clients or customers. Service Organizations or, if applicable, their designees
that have entered into agreements with the Fund or its agent may enter confirmed
purchase orders on behalf of clients and customers, with payment to follow no
later than the Fund's pricing on the following Business Day. If payment is not
received by such time, the Service Organization could be held liable for
resulting fees or losses. The Fund will be deemed to have received a purchase or
redemption order when a Service Organization, or, if applicable, its authorized
designee, accepts a purchase or redemption order in good order. Orders received
by the Fund in good order will be priced at the Fund's net asset value next
computed after they are accepted by the Service Organization or its authorized
designee.

-7-

<PAGE>

For administration, subaccounting, transfer agency and/or other services,
Boston Partners, the Distributor or their affiliates may pay Service
Organizations and certain recordkeeping organizations a fee of up to .35% (the
"Service Fee") of the average annual value of accounts with the Fund maintained
by such Service Organizations or recordkeepers. The Service Fee payable to any
one Service Organization is determined based upon a number of factors, including
the nature and quality of services provided, the operations processing
requirements of the relationship and the standardized fee schedule of the
Service Organization or recordkeeper.

The Adviser, the Distributor or either of their affiliates may, at their
own expense, provide promotional incentives for qualified recipients who support
the sale of Shares, consisting of securities dealers who have sold Shares or
others, including banks and other financial institutions, under special
arrangements. Incentives may include opportunities to attend business meetings,
conferences, sales or training programs for recipients, employees or clients and
other programs or events and may also include opportunities to participate in
advertising or sales campaigns and/or shareholder services and programs
regarding one or more Boston Partners Funds. Travel, meals and lodging may also
be paid in connection with these promotional activities. In some instances,
these incentives may be offered only to certain institutions whose
representatives provide services in connection with the sale or expected sale of
significant amounts of Shares.

HOW TO PURCHASE SHARES
- --------------------------------------------------------------------------------

GENERAL

Shares representing interests in the Fund are offered continuously for sale
by the Distributor and may be purchased without imposition of a sales charge.
Shares may be purchased initially by completing the application included in this
Prospectus and forwarding the application to the Fund's transfer agent, PFPC.
Purchases of Shares may be effected by wire to an account to be specified by
PFPC or by mailing a check or Federal Reserve Draft, payable to the order of
"The Boston Partners Mid Cap Value Fund," c/o PFPC Inc., P.O. Box 8852,
Wilmington, Delaware 19899-8852. The name of the Fund, Boston Partners Mid Cap
Value Fund, must also appear on the check or Federal Reserve Draft. Shareholders
may not purchase shares of the Boston Partners Mid Cap Value Fund with a check
issued by a third party and endorsed over to the fund. Federal Reserve Drafts
are available at national banks or any state bank which is a member of the
Federal Reserve System. Initial investments in the Fund must be at least $2,500
and subsequent investments must be at least $100. The Fund reserves the right to
suspend the offering of Shares for a period of time or to reject any purchase
order.

Shares may be purchased on any Business Day. A "Business Day" is any day
that the New York Stock Exchange, Inc. (the "NYSE") is open for business.
Currently, the NYSE is closed on weekends and New Year's Day, Dr. Martin Luther
King, Jr. Day, Presidents' Day, Good Friday, Memorial Day, Independence Day,
Labor Day, Thanksgiving Day and Christmas Day and on the preceding Friday or
subsequent Monday when one of these holidays falls on a Saturday or Sunday.

The price paid for Shares purchased initially or acquired through the
exercise of an exchange privilege is based on the net asset value next computed
after a purchase order is received in good order by the Fund or its agents.
Orders received by the Fund or its agents prior to the close of the NYSE
(generally 4:00 p.m. Eastern Time) are priced at that Business Day's net asset
value. Orders received by the Fund or its agents after the close of the NYSE are
priced at the net asset value next determined on the following Business Day. In
those cases where an investor pays for Shares by check, the purchase will be
effected at the net asset value next determined after the Fund or its agents
receives the order and the completed application.

Provided that the investment is at least $2,500, an investor may also
purchase Shares by having his bank or his broker wire Federal Funds to PFPC. The
Fund does not currently impose a service charge for effecting wire transfers,

-8-

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK)

<PAGE>

but reserves the right to do so in the future. An investor's bank or broker may
impose a charge for this service. In order to ensure prompt receipt of an
investor's Federal Funds wire for an initial investment, it is important that an
investor follows these steps:

A. Telephone the Fund's transfer agent, PFPC, toll-free (888)
261-4073, and provide PFPC with your name, address, telephone number,
Social Security or Tax Identification Number, the Fund selected, the
amount being wired, and by which bank. PFPC will then provide an
investor with a Fund account number. Investors with existing accounts
should also notify PFPC prior to wiring funds.

B. Instruct your bank or broker to wire the specified amount,
together with your assigned account number, to PFPC's account with PNC:

PNC Bank, N.A.
Philadelphia, PA 19103
ABA NUMBER: 0310-0005-3
CREDITING ACCOUNT NUMBER: 86-1108-2507
FROM: (name of investor)
ACCOUNT NUMBER: (Investor's account number with the
Fund)
FOR PURCHASE OF: Boston Partners Mid Cap Value Fund
AMOUNT: (amount to be invested)

C. Fully complete and sign the application and mail it to the
address shown thereon. PFPC will not process purchases until it
receives a fully completed and signed application.

For subsequent investments, an investor should follow steps A and B above.

AUTOMATIC INVESTING

Additional investments in Shares may be made automatically by authorizing
the Fund's transfer agent to withdraw funds from your bank account. Investors
desiring to participate in the Automatic Investment Plan should call the Fund's
transfer agent, PFPC, at (888)261-4073 to obtain the appropriate forms.

RETIREMENT PLANS

Shares may be purchased in conjunction with individual retirement accounts
("IRAs") and rollover IRAs where PNC Bank acts as custodian. For further
information as to applications and annual fees, contact the Fund's transfer
agent, PFPC, at (888) 261-4073. To determine whether the benefits of an IRA are
available and/or appropriate, a shareholder should consult with a tax adviser.

HOW TO REDEEM AND EXCHANGE SHARES
- --------------------------------------------------------------------------------

REDEMPTION BY MAIL

-9-

<PAGE>

SYSTEMATIC WITHDRAWAL PLAN

If your account has a value of at least $10,000, you may establish a
Systematic Withdrawal Plan and receive regular periodic payments. A request to
establish a Systematic Withdrawal Plan must be submitted in writing to PFPC at
P.O. Box 8852, Wilmington, Delaware 19899-8852. Each withdrawal redemption will
be processed on or about the 25th of the month and mailed as soon as possible
thereafter. There are no service charges for maintenance; the minimum amount
that you may withdraw each period is $100. (This is merely the minimum amount
allowed and should not be mistaken for a recommended amount.) The holder of a
Systematic Withdrawal Plan will have any income dividends and any capital gains
distributions reinvested in full and fractional shares at net asset value. To
provide funds for payment, Shares will be redeemed in such amount as is
necessary at the redemption price, which is net asset value next determined
after the Fund's receipt of a redemption request. Redemption of Shares may
reduce or possibly exhaust the Shares in your account, particularly in the event
of a market decline. As with other redemptions, a redemption to make a
withdrawal payment is a sale for federal income tax purposes. Payments made
pursuant to a Systematic Withdrawal Plan cannot be considered as actual yield or
income since part of such payments may be a return of capital.

INVOLUNTARY REDEMPTION

PAYMENT OF REDEMPTION PROCEEDS

In all cases, the redemption price is the net asset value per share next
determined after the request for redemption is received in proper form by the
Fund or its agents. Payment for Shares redeemed is made by check mailed within
seven days after acceptance by the Fund or its agents of the request and any
other necessary documents in proper order. Such payment may be postponed or the
right of redemption suspended as permitted by the 1940 Act. If the Shares to be
redeemed have been recently purchased by check, the Fund's transfer agent may
delay mailing a redemption check, which may be a period of up to 15 days,
pending a determination that the check has cleared. The Fund has elected to be
governed by Rule 18f-1 under the 1940 Act so that it is obligated to redeem its
shares solely in cash up to the lesser of $250,000 or 1% of its net asset value
during any 90-day period for any one shareholder of a portfolio.

EXCHANGE PRIVILEGE

-10-

<PAGE>

Value Fund or the Boston Partners Bond Fund subject to the restrictions
described under "Exchange Privilege Limitations." Such exchange will be effected
at the net asset value of the exchanged Fund and the net asset value of the
Boston Partners Large Cap Value Fund or the Boston Partners Bond Fund next
determined after receipt of a request for an exchange by the Fund or its agents.
An exchange of Shares will be treated as a sale for federal income tax purposes.
See "Taxes." A shareholder wishing to make an exchange may do so by sending a
written request to PFPC.

If the exchanging shareholder does not currently own Investor Shares of the
Boston Partners Large Cap Value Fund or Boston Partners Bond Fund, a new account
will be established with the same registration, dividend and capital gain
options as the account from which shares are exchanged, unless otherwise
specified in writing by the shareholder with all signatures guaranteed. A
signature guarantee may be obtained from a domestic bank or trust company,
broker, dealer, clearing agency or savings association who are participants in a
medallion program recognized by the Securities Transfer Association. The three
recognized medallion programs are Securities Transfer Agents Medallion Program
(STAMP), Stock Exchanges Medallion Program (SEMP) and New York Stock Exchange,
Inc. Medallion Signature Program (MSP). Signature guarantees that are not part
of these programs will not be accepted. The exchange privilege may be modified
or terminated at any time, or from time to time, by RBB, upon 60 days' written
notice to shareholders.

If an exchange is to a new account in the Boston Partners Large Cap Value
Fund or Boston Partners Bond Fund, the dollar value of Investor Shares acquired
must equal or exceed RBB's minimum for a new account; if to an existing account,
the dollar value must equal or exceed that Fund's minimum for subsequent
investments. If any amount remains in the Fund from which the exchange is being
made, such amount must not drop below the minimum account value required by the
Fund.

EXCHANGE PRIVILEGE LIMITATIONS

The Fund's exchange privilege is not intended to afford shareholders a way
to speculate on short-term movements in the market. Accordingly, in order to
prevent excessive use of the exchange privilege that may potentially disrupt the
management of the Funds and increase transactions costs, the Fund has
established a policy of limiting excessive exchange activity.

Shareholders are entitled to six (6) exchange redemptions (at least 30 days
apart) from the Fund during any twelve-month period. Notwithstanding these
limitations, the Fund reserves the right to reject any purchase request
(including exchange purchases from the Boston Partners Large Cap Value Fund and
Boston Partners Bond Fund) that is deemed to be disruptive to efficient
portfolio management.

TELEPHONE TRANSACTIONS

In order to request an exchange or redemption by telephone, a shareholder
must have completed and returned an account application containing the
appropriate telephone election. To add a telephone option to an existing account
that previously did not provide for this option, a Telephone Authorization Form
must be filed with PFPC. This form is available from PFPC. Once this election
has been made, the shareholder may simply contact PFPC by telephone to request
an exchange or redemption by calling (888) 261-4073. Neither RBB, the Fund, the
Distributor, the Administrator nor any other Fund agent will be liable for any
loss, liability, cost or expense for following RBB's telephone transaction
procedures described below or for following instructions communicated by
telephone that they reasonably believe to be genuine.

-11-

<PAGE>

account of record; (6) sending a written confirmation for each telephone
transaction to the owners of record at the address of record within five (5)
Business Days of the call; and (7) maintaining tapes of telephone transactions
for six months, if the Fund elects to record shareholder telephone transactions.
For accounts held of record by broker-dealers (other than the Distributor),
financial institutions, securities dealers, financial planners and other
industry professionals, additional documentation or information regarding the
scope of a caller's authority is required. Finally, for telephone transactions
in accounts held jointly, additional information regarding other account holders
is required. Telephone transactions will not be permitted in connection with IRA
or other retirement plan accounts or by an attorney-in-fact under a power of
attorney.

NET ASSET VALUE
- --------------------------------------------------------------------------------

The net asset values for each class of a fund are calculated by adding the
value of the proportionate interest of the class in a fund's cash, securities
and other assets, deducting actual and accrued liabilities of the class and
dividing the result by the number of outstanding shares of the class. The net
asset values of each class are calculated separately from each other class. The
net asset values are calculated as of the close of regular trading on the NYSE,
generally 4:00 p.m. Eastern time on each Business Day.

DIVIDENDS AND DISTRIBUTIONS
- --------------------------------------------------------------------------------

The Fund will distribute substantially all of the net investment income and
net realized capital gains, if any, of the Fund to the Fund's shareholders. All
distributions are reinvested in the form of additional full and fractional
Shares unless a shareholder elects otherwise.

TAXES
- --------------------------------------------------------------------------------

-12-

<PAGE>

taxes on amounts so distributed (except distributions that are treated as a
return of capital) regardless of whether such distributions are paid in cash or
reinvested in additional shares.

Distributions out of the "net capital gain" (the excess of net long-term
capital gain over net short-term capital loss), if any, of the Fund, and out of
the portion of such net capital gain that constitutes mid-term capital gain,
will be taxed to shareholders as long-term capital gain or mid-term capital
gain, as the case may be, regardless of the length of time a shareholder has
held his Shares, whether such gain was reflected in the price paid for the
Shares, or whether such gain was attributable to bonds bearing tax-exempt
interest. All other distributions, to the extent they are taxable, are taxed to
shareholders as ordinary income.

Shareholders who exchange shares representing interests in one Fund for
shares representing interests in another Fund will generally recognize capital
gain or loss for federal income tax purposes.

Shareholders who are nonresident alien individuals, foreign trusts or
estates, foreign corporations or foreign partnerships may be subject to
different U.S. federal income tax treatment.

MULTI-CLASS STRUCTURE
- --------------------------------------------------------------------------------

The Fund offers one other class of shares, Institutional Shares, which is
offered directly to institutional investors pursuant to a separate prospectus.
Shares of each class represent equal pro rata interests in the Fund and accrue
dividends and calculate net asset value and performance quotations in the same
manner. The Fund will quote performance of Institutional Shares separately from
Investor Shares. Because of different expenses paid by the Investor Shares, the
total return on such shares can be expected, at any time, to be different than
the total return on Institutional Shares. Information concerning Institutional
Shares may be obtained by calling the Fund at (888) 261-4073.

DESCRIPTION OF SHARES
- --------------------------------------------------------------------------------

THIS PROSPECTUS AND THE STATEMENT OF ADDITIONAL INFORMATION INCORPORATED
HEREIN RELATE PRIMARILY TO THE BOSTON PARTNERS MID CAP VALUE FUND AND DESCRIBE
ONLY THE INVESTMENT OBJECTIVES AND POLICIES, OPERATIONS, CONTRACTS AND OTHER
MATTERS RELATING TO THE BOSTON PARTNERS MID CAP VALUE FUND.

Each share that represents an interest in the Fund has an equal
proportionate interest in the assets belonging to the Fund with each other share
that represents an interest in the Fund, even where a share has a different
class designation than another share representing an interest in that portfolio.
Shares of the Fund do not have preemptive or conversion rights. When issued for
payment as described in this Prospectus, Shares will be fully paid and
non-assessable.

-13-

<PAGE>

RBB currently does not intend to hold annual meetings of shareholders
except as required by the 1940 Act or other applicable law. The law under
certain circumstances provides shareholders with the right to call for a meeting
of shareholders to consider the removal of one or more directors. To the extent
required by law, RBB will assist in shareholder communication in such matters.

As of November 15, 1997, to the Fund's knowledge, no person held of record
or beneficially 25% or more of the outstanding shares of all classes of RBB.

OTHER INFORMATION
- --------------------------------------------------------------------------------

REPORTS AND INQUIRIES

Shareholders will receive unaudited semi-annual reports describing the
Fund's investment operations and annual financial statements audited by
independent accountants. Shareholder inquiries should be addressed to PFPC Inc.,
the Fund's transfer agent, Bellevue Park Corporate Center, 400 Bellevue Parkway,
Wilmington, Delaware 19809, toll-free (888) 261-4073.

SHARE CERTIFICATES

In the interest of economy and convenience, physical certificates
representing shares in the Fund are not normally issued.

HISTORICAL PERFORMANCE INFORMATION

For the period from commencement of operations (June 2, 1997) through
August 31, 1997, the total return (not annualized) for the Investor Class of
Shares of the Fund was as follows:

Unannualized investment returns for the period ended August 31, 1997

Since
INCEPTION
---------
Boston Partners Mid Cap Value Fund
(Investor Shares)................................ 10.10%

The total return assumes the reinvestment of all dividends and capital
gains and reflects investment advisory fee waivers and expense reimbursements in
effect. Without these waivers and expense reimbursements, the Fund's performance
would have been lower. Of course, past performance is no guarantee of future
results. Investment return and principal value will fluctuate, so that Shares,
when redeemed, may be worth more or less than the original cost. For more
information on performance, see "Performance Information" in the Statement of
Additional Information.

-14-

<PAGE>

The table below presents the Composite performance history of certain of
the Adviser's managed accounts on an annualized basis for the period ended
August 31, 1997. The Composite is comprised of the Adviser's institutional
accounts and other privately managed accounts with investment objectives,
policies and strategies substantially similar to those of the Fund, although the
accounts have longer operating histories than the Fund which commenced
operations on June 2, 1997. The Composite performance information includes the
reinvestment of dividends received in the underlying securities and reflects
investment advisory fees. The privately managed accounts in the Composite are
only available to the Adviser's institutional advisory clients. The past
performance of the funds and accounts that comprise the Composite is not
indicative of or a substitute for the future performance of the Fund. These
accounts have lower investment advisory fees than the Fund and the Composite
performance figures would have been lower if subject to the higher fees and
expenses incurred by the Fund. These private accounts are not subject to the
same investment limitations, diversification requirements and other restrictions
which are imposed upon mutual funds under the 1940 Act and the Internal Revenue
Code, which, if imposed, may have adversely affected the performance results of
the Composite. Listed below the performance history for the Composite is the
performance history for a comparative index comprised of securities similar to
those in which accounts contained in the Composite are invested.

Annualized investment returns for the period ended August 31, 1997

Since
ONE YEAR INCEPTION
-------- ---------
Composite Performance.............. 51.0% 37.8%*
Russell 2500 Index................. 31.5% 25.9%

* The Adviser commenced managing these accounts on May 1, 1995.

The Russell 2500 Index represents the largest 3000 companies domiciled in
the United States minus the largest 500 companies as determined by the market
value of such companies.

FUTURE PERFORMANCE INFORMATION

From time to time, the Fund may advertise its performance, including
comparisons to other mutual funds with similar investment objectives and to
stock or other relevant indices. All such advertisements will show the average
annual total return over one, five and ten year periods or, if such periods have
not yet elapsed, shorter periods corresponding to the life of the Fund. Such
total return quotations will be computed by finding the compounded average
annual total return for each time period that would equate the assumed initial
investment of $1,000 to the ending redeemable value, net of fees, according to a
required standardized calculation. The standard calculation is required by the
SEC to provide consistency and comparability in investment company advertising.
The Fund may also from time to time include in such advertising an aggregate
total return figure or a total return figure that is not calculated according to
the standardized formula in order to compare more accurately the Fund's
performance with other measures of investment return. For example, the Fund's
total return may be compared with data published by Lipper Analytical Services,
Inc., CDA Investment Technologies, Inc. or Weisenberger Investment Company
Service, or with the performance of the Russell 2500 Index. Performance
information may also include evaluation of the Fund by nationally recognized
ranking services and information as reported in financial publications such as
BUSINESS WEEK, FORTUNE, INSTITUTIONAL INVESTOR, MONEY MAGAZINE, FORBES,
BARRON'S, THE WALL STREET JOURNAL, THE NEW YORK TIMES, or other national,
regional or local publications. All advertisements containing performance data
will include a legend disclosing that such performance data represents past
performance and that the investment return and principal value of an investment
will fluctuate so that an investor's Shares, when redeemed, may be worth more or
less than their original cost.

-15-

<PAGE>

NO PERSON HAS BEEN AUTHORIZED TO GIVE ANY
INFORMATION OR MAKE ANY REPRESENTATIONS NOT
CONTAINED IN THIS PROSPECTUS OR IN RBB'S STATEMENT
OF ADDITIONAL INFORMATION INCORPORATED HEREIN BY
REFERENCE, IN CONNECTION WITH THE OFFERING MADE BY
THIS PROSPECTUS AND, IF GIVEN OR MADE, SUCH PROSPECTUS
REPRESENTATIONS MUST NOT BE RELIED UPON AS HAVING
BEEN AUTHORIZED BY RBB OR ITS DISTRIBUTOR. THIS DECEMBER 1, 1997
PROSPECTUS DOES NOT CONSTITUTE AN OFFERING BY RBB (as revised May 29, 1998)
OR BY THE DISTRIBUTOR IN ANY JURISDICTION IN WHICH
SUCH OFFERING MAY NOT LAWFULLY BE MADE.
------------------------

TABLE OF CONTENTS
PAGE

FINANCIAL HIGHLIGHTS.......................... 2
INTRODUCTION.................................. 4
INVESTMENT OBJECTIVES AND POLICIES............ 4
INVESTMENT LIMITATIONS........................ 5
RISK FACTORS.................................. 5
MANAGEMENT.................................... 6
DISTRIBUTION OF SHARES........................ 7 BOSTON PARTNERS
HOW TO PURCHASE SHARES........................ 8 MID CAP VALUE FUND
HOW TO REDEEM AND EXCHANGE SHARES............. 9 (Investor Shares)
NET ASSET VALUE............................... 12
DIVIDENDS AND DISTRIBUTIONS................... 12
TAXES ..................................... 12
MULTI-CLASS STRUCTURE......................... 13
DESCRIPTION OF SHARES......................... 13
OTHER INFORMATION............................. 14

INVESTMENT ADVISER
Boston Partners Asset Management, L.P.
Boston, Massachusetts

CUSTODIAN
PNC Bank, N.A.
Philadelphia, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

DISTRIBUTOR bp
Provident Distributors, Inc.
West Conshohocken, Pennsylvania
Boston Partners Asset Management, L.P.
--------------------------------------
COUNSEL
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

INDEPENDENT ACCOUNTANTS
Coopers & Lybrand L.L.P.
Philadelphia, Pennsylvania

(LOGO)
(GRAPHIC OMITTED)
<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND bp
(INVESTOR CLASS) BOSTON PARTNERS ASSET MANAGEMENT, L.P.

ACCOUNT APPLICATION
PLEASE NOTE: Do not use this form to open a retirement plan account. For an IRA application or help with this Application, please
call 1-888-261-4073.

<S> <C>
- ---------------- (Please check the appropriate box(es) below.)
| 1 | [Checkbox] Individual [Checkbox] Joint Tenant [Checkbox] Other
| Account |
| Registration:| ----------------------------------------------------------------------------------------------------------------
- ---------------- Name SOCIAL SECURITY NUMBER OR TAX ID # OF PRIMARY OWNER

----------------------------------------------------------------------------------------------------------------
NAME OF MINOR (ONLY ONE PERMITTED)

----------------------------------------------------------------------------------------------------------------
MINOR'S SOCIAL SECURITY NUMBER AND DATE OF BIRTH

----------------------------------------------------------------------------------------------------------------
TAXPAYER IDENTIFICATION NUMBER

----------------------------------------------------------------------------------------------------------------
DAY PHONE NUMBER EVENING PHONE NUMBER

</TABLE>

<PAGE>

<TABLE>
<CAPTION>
<S> <C>
-A minimum account value of $10,000 in a single account is required to establish a Systematic Withdrawal Plan
-Payments will be made on or near the 25th of the month
Please check one of the following options: ________ Please mail checks to Address of Record (Named in
Section 2)
________ Please electronically credit my Bank of Record
(Named in Section 5)

-------------------------- --------------------------- Exchange shares for shares of The Boston
individual initial joint initial Partners Large Cap Value Fund or Boston
Partners Bond Fund.
</TABLE>

<S> <C>

- ---------------- The Automatic Investment Plan, which is available to shareholders of the Fund, makes possible regularly
| 5 | scheduled purchases of Fund shares to allow dollar-cost averaging. The Fund's Transfer Agent can arrange for
| Automatic | an amount of money selected by you to be deducted from your checking account and used to purchase shares of the
| Investment | Fund.
| Plan: |
- ----------------

-----------------------------------------------------------------------------------------------------------------
BANK ABA NUMBER BANK ACCOUNT NUMBER

- ---------------- The undersigned warrants that I (we) have fully authority and, if a natural person, I (we) am (are) of legal age
| 6 | to purchase shares pursuant to this Account Application, and I (we) have received a current prospectus for the
| | Fund in which I (we) am (are) investing.
| Signatures: | Under the Interest and Dividend Tax Compliance Act of 1983, the Fund is required to have the following
- ---------------- certification:
Under penalties of perjury, I certify that:
(1) The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to
be issued to me), and
(2) I am not subject to backup withholding because (a) I am exempt from backup withholding, or (b) I have not
been notified by the Internal Revenue Service that I am subject to 31% backup withholding as a result of a
failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup
withholding.

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF APPLICANT DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

-----------------------------------------------------------------------------------------------------------------
SIGNATURE OF JOINT OWNER DATE

-----------------------------------------------------------------------------------------------------------------
PRINT NAME TITLE (IF APPLICABLE)

For information on additional options, such as IRA Applications, rollover requests for qualified retirement
plans, or for wire instructions, please call us at 1-888-261-4073.

MAIL COMPLETED ACCOUNT APPLICATION AND CHECK TO: THE BOSTON PARTNERS MID CAP VALUE FUND
C/O PFPC INC.
P.O. BOX 8852
WILMINGTON, DE 19899-8852

</TABLE>