RBB FUND INC, 497, 2000-03-28

RBB FUND INC
497, 2000-03-28

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PROSPECTUS

DECEMBER 1, 1999
(as revised March 28, 2000)

BOSTON PARTNERS
LARGE CAP VALUE FUND

BOSTON PARTNERS
MID CAP VALUE FUND

BOSTON PARTNERS
SMALL CAP VALUE FUND II

BOSTON PARTNERS
BOND FUND

BOSTON PARTNERS
MARKET NEUTRAL FUND

INSTITUTIONAL CLASS

bp (LOGO)
BOSTON PARTNERS ASSET MANAGEMENT, L.P.
[GRAPHIC OMITTED]

<PAGE>

BOSTON PARTNERS FAMILY OF FUNDS
OF
THE RBB FUND, INC.

INSTITUTIONAL CLASS

BOSTON PARTNERS FAMILY OF FUNDS

LARGE CAP VALUE FUND

MID CAP VALUE FUND

SMALL CAP VALUE FUND II

BOND FUND

MARKET NEUTRAL FUND

- --------------------------------------------------------------------------------
THE SECURITIES DESCRIBED IN THIS PROSPECTUS HAVE BEEN REGISTERED WITH THE
SECURITIES AND EXCHANGE COMMISSION (THE "SEC"). THE SEC, HOWEVER, HAS NOT JUDGED
THESE SECURITIES FOR THEIR INVESTMENT MERIT AND HAS NOT DETERMINED THE ACCURACY
OR ADEQUACY OF THIS PROSPECTUS. ANYONE WHO TELLS YOU OTHERWISE IS COMMITTING A
CRIMINAL OFFENSE.
- --------------------------------------------------------------------------------
PROSPECTUS December 1, 1999
(as revised March 28, 2000)
<PAGE>

TABLE OF CONTENTS
- --------------------------------------------------------------------------------

================================ INTRODUCTION ................................ 3

DESCRIPTIONS OF THE BOSTON PARTNERS FUNDS

Boston Partners Large Cap Value Fund ...... 4

Boston Partners Mid Cap Value Fund ........ 9
A LOOK AT THE GOALS, STRATEGIES,
RISKS, EXPENSES AND FINANCIAL Boston Partners Small Cap Value Fund II....14
HISTORY OF EACH OF THE
BOSTON PARTNERS FUNDS. Boston Partners Bond Fund .................19

Boston Partners Market Neutral Fund .......24

MANAGEMENT

Investment Adviser ........................28
DETAILS ABOUT THE SERVICE
PROVIDERS. Service Provider Chart ....................30

SHAREHOLDER INFORMATION
POLICIES AND INSTRUCTIONS FOR
OPENING, MAINTAINING AND Pricing of Fund Shares ....................31
CLOSING AN ACCOUNT IN ANY OF
THE BOSTON PARTNERS FUNDS. Purchase of Fund Shares ...................31
================================
Redemption of Fund Shares .................32

Exchange Privilege ........................34

Dividends and Distributions ...............35

Taxes .....................................35

Multi-Class Structure .....................36

FOR MORE INFORMATION ................Back Cover

<PAGE>

INTRODUCTION TO THE RISK/RETURN SUMMARY
- --------------------------------------------------------------------------------

This Prospectus has been written to provide you with the information you
need to make an informed decision about whether to invest in the Institutional
Class of the Boston Partners Family of Funds of The RBB Fund, Inc.
(the "Company").

The five mutual funds of the Company offered by this Prospectus represent
interests in the Boston Partners Large Cap Value Fund, Boston Partners Mid Cap
Value Fund, Boston Partners Small Cap Value Fund II, Boston Partners Bond Fund
and Boston Partners Market Neutral Fund (each a "Fund" and collectively, the
"Funds"). This Prospectus and the Statement of Additional Information
incorporated herein relate solely to the Funds.

This Prospectus has been organized so that each Fund has its own short
section with important facts about that particular Fund. Once you read the short
sections about the Funds that interest you, read the "Purchase of Fund Shares"
and "Redemption of Fund Shares" sections. These two sections apply to all the
Funds offered by this Prospectus.

<PAGE>

BOSTON PARTNERS LARGE CAP VALUE FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

EQUITY SECURITY: A security, such as a stock, representing ownership of a
company. Bonds, in comparison, are referred to as fixed-income or debt
securities because they represent indebtedness to the bondholder, not ownership.

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

VALUE CHARACTERISTICS: Stocks are generally divided into the categories of
"growth" or "value." Value stocks appear to the Adviser to be undervalued by the
market as measured by certain financial formulas. Growth stocks appear to the
Adviser to have earnings growth potential that is greater than the market in
general, and whose growth in revenue is expected to continue for an extended
period of time.

EARNINGS GROWTH: The increased rate of growth in a company's earnings per share
from period to period. Security analysts attempt to identify companies with
earnings growth potential because a pattern of earnings growth generally causes
share prices to increase.
================================================================================

INVESTMENT GOALS

The Fund seeks to provide long-term growth of capital with current income
as a secondary objective.

PRIMARY INVESTMENT STRATEGIES

The Fund invests (during 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 Boston Partners Asset Management L.P. (the "Adviser") as possessing value
characteristics. The Fund may also invest up to 20% of its total assets in
non-U.S. dollar denominated securities.

The Adviser examines various factors in determining the value
characteristics of such issuers including 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 and
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.

While the Adviser intends to fully invest the Fund's assets at all times in
accordance with the policies above, 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.

KEY RISKS

(BULLET) At least 65% of the Fund's total assets will be invested in a
diversified portfolio of equity securities, and the net asset value
("NAV") of the Fund will change with changes in the market value of its
portfolio positions.

(BULLET) Investors may lose money.

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

(BULLET) Convertible securities frequently have speculative characteristics
and may be acquired without regard to minimum quality ratings.
Convertible securities and obligations rated in the lowest of the top
four rating categories are subject to greater credit and interest rate
risk than higher rated securities.

<PAGE>

(BULLET) The Fund may, for temporary defensive purposes, invest a
percentage of its total assets, without limitation, in cash or various
U.S. dollar-denominated money market instruments. The value of money
market instruments tends to fall when current interest rates rise. Money
market instruments are generally less sensitive to interest rate changes
than longer-term securities. When the Fund's assets are invested in these
instruments, the Fund may not be achieving its investment objective.

(BULLET) International investing is subject to special risks, including,
but not limited to, currency exchange rate volatility, political, social
or economic instability, and differences in taxation, auditing and other
financial practices.

(BULLET) The Fund may experience relatively large purchases or redemptions
due to asset allocation decisions made by the Adviser for clients
receiving asset allocation account management services involving
investments in the Fund. These transactions may have a material effect on
the Fund, since redemptions caused by reallocations may result in the
Fund selling portfolio securities it might not otherwise sell, resulting
in a higher portfolio turnover rate, and purchases caused by
reallocations may result in the Fund receiving additional cash that will
remain uninvested until additional securities can be purchased. The
Adviser will attempt to minimize the effects of these transactions at all
times.

(BULLET) The Fund could be affected if the computer systems on which it
relies do not properly process information beginning on January 1, 2000.
While Year 2000 issues could have a negative effect on the Fund, the
Adviser is currently working to avoid such problems. The Adviser is also
working with the Fund's other service providers and vendors to determine
their systems' ability to handle Year 2000 problems. There is no
guarantee that the systems will work properly on January 1, 2000. Year
2000 problems may also hurt issuers whose securities the Fund holds or
securities markets generally.

PRIOR PERFORMANCE
ANNUAL TOTAL RETURNS AS OF DECEMBER 31
The bar chart below shows the variability of the annual total returns for
the Institutional Class of the Fund for the last two calendar years. The bar
chart provides some indication of the risks of investing in the Fund by showing
changes in the performance of the Fund's Institutional Class from year to year.
Past performance is not necessarily an indicator of how the Fund will perform in
the future.

[GRAPHIC OMITTED]

EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

1997 31.09
1998 (0.64%)

<PAGE>

Since inception (January 2, 1997), the highest calendar quarter total
return for the Institutional Class of the Fund was 15.39% (quarter ended June
30, 1997) and the lowest calendar quarter total return was (16.02)% (quarter
ended September 30, 1998). The total return was (10.93)% for the nine months
ended September 30, 1999.

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Institutional
Class, compare with the Standard & Poor's 500 Composite Stock Price Index (the
"S&P 500 Index") for the same periods. The S&P 500 Index is an unmanaged index
composed of 500 common stocks, most of which are listed on the New York Stock
Exchange. The S&P 500 Index assigns relative values to the stocks included in
the index, weighted accordingly to each stock's total market value relative to
the total market value of the other stocks included in the index. The table,
like the bar chart, provides some indication of the risks of investing in the
Fund by showing how the Fund's average annual total returns for 1 year and since
inception compare with those of a broad measure of market performance. Past
performance is not necessarily an indicator of how the Fund will perform in the
future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------ ---------------
Institutional Class (.64)% 14.15%*
S&P 500 Index 28.57% 30.99%

*Commenced operations on January 2, 1997.

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Institutional Class of the
Fund. The table is based on expenses for the Institutional Class of the Fund for
the most recent fiscal year ended August 31, 1999.

INSTITUTIONAL CLASS
-------------------
ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ......................................... 0.75%
Distribution (12b-1) fees ............................... None
Other expenses(1) ....................................... 0.55%
----
Total annual Fund operating expenses ................ 1.30%
Fee waivers(2) .......................................... 0.30%
----
Net expenses ............................................ 1.00%
====

(1) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Institutional Class.

(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.00%.

<PAGE>

EXAMPLE

The example is intended to help you compare the cost of investing in the
Institutional Class of the Fund with the cost of investing in other mutual
funds. The example assumes that you invest $10,000 in the Institutional Class of
the Fund for the time periods indicated and then redeem all of your shares at
the end of each period. The example also assumes that your investment has a 5%
return each year and that the operating expenses of the Institutional Class of
the Fund remain the same, except for the expiration of the fee waivers and
reimbursements on December 31, 2000. Although your actual costs may be higher or
lower, based on these assumptions your cost would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$102 $383 $684 $1,541

<PAGE>

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

LARGE CAP VALUE FUND
-------------------------------------------------
FOR THE FOR THE FOR THE PERIOD
YEAR ENDED YEAR ENDED JANUARY 2, 1997*
AUGUST 31, AUGUST 31, THROUGH AUGUST 31,
1999 1998 1997
------------- ------------- ------------------
INSTITUTIONAL INSTITUTIONAL INSTITUTIONAL
CLASS CLASS CLASS
------------- ------------- ------------------
<S> <C> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ............................. $ 10.58 $ 12.46 $ 10.00
------- ------- -------
Net investment income/(loss) (1) ................................. 0.05 0.12 0.05
Net realized and unrealized gain/(loss) on investments (2) ....... 1.76 (1.31) 2.41
------- ------- -------
Net increase/(decrease) in net assets resulting from operations .. 1.81 (1.19) 2.46
------- ------- -------
Dividends to shareholders from:
Net investment income ............................................ (0.04) (0.08) --
Net realized capital gains ....................................... (0.11) (0.61) --
------- ------- -------
Total dividends and distributions to shareholders ................ (0.15) (0.69) --
------- ------- -------
Net asset value, end of period ................................... $ 12.24 $ 10.58 $ 12.46
======= ======= =======
Total investment return .......................................... 17.12% (10.23%) 24.60%(3)
======= ======= =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) ..................... $53,112 $50,724 $24,603
Ratio of expenses to average net assets (1) ................... 1.00% 1.00% 1.00%(4)
Ratio of expenses to average net assets without
waivers and expense reimbursements .......................... 1.30% 1.49% 2.64%(4)
Ratio of net investment income to average net assets (1) ...... 0.61% 0.87% 1.19%(4)
Portfolio turnover rate ....................................... 156.16% 111.68% 67.16%
<FN>
- ------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

INVESTMENT GOALS

The Fund seeks to provide long-term growth of capital primarily through
investment in equity securities. Current income is a secondary goal.

PRIMARY INVESTMENT STRATEGIES

The Fund pursues its goal 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 $6 billion and identified by Boston Partners Asset
Management L.P.(the "Adviser") as having value characteristics.

The Adviser examines various factors in determining the value
characteristics of such issuers including 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, and
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.

The Fund may also invest up to 20% of its total assets in non U.S.
dollar-denominated securities.

In general, the Fund's investments are broadly diversified over a number of
industries and, as a matter of policy, the Fund is limited to investing a
maximum of 25% of its total assets in any one industry.

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.

KEY RISKS

(BULLET) At least 65% of the Fund's total assets will be invested under
normal market conditions in a diversified portfolio of equity securities,
and the net asset value ("NAV") of the Fund will change with changes in
the market value of its portfolio positions.

(BULLET) Investors may lose money.

9
<PAGE>

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

(BULLET) If the Fund frequently trades its portfolio securities, the Fund
will incur higher brokerage commissions and transaction costs, which
could lower the Fund's performance. In addition to lower performance,
high portfolio turnover could result in taxable capital gains. The annual
portfolio turnover rate for the Fund is not expected to exceed 150%,
however, it may be higher if the Adviser believes it will improve the
Fund's performance.

PRIOR PERFORMANCE

ANNUAL TOTAL RETURNS AS OF DECEMBER 31

The bar chart below shows the total return for the Institutional Class of
the Fund during its first full calendar year. Past performance is not
necessarily an indicator of how the Fund will perform in the future.

[GRAPHIC OMITTED]

EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

1998
-----
(2.20%)

Since inception (June 2, 1997), the highest calendar quarter total return
for the Institutional Class of the Fund was 13.55% (quarter ended March 31,
1998) and the lowest calendar quarter total return was (20.90)% (quarter ended
September 30, 1998). The total return was (10.20)% for the nine months ended
September 30, 1999.

<PAGE>

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Institutional
Class, compare with the Russell 2500 Index for the same periods. The Russell
2500 Index is an unmanaged index (with no defined investment objective) of
common stocks, includes reinvestment of dividends and is a registered trademark
of the Frank Russell Corporation. The table, like the bar chart, provides some
indication of the risks of investing in the Fund by showing how the Fund's
average annual total returns for 1 year and since inception compare with those
of a broad measure of market performance. Past performance is not necessarily an
indicator of how the Fund will perform in the future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------- ---------------
Institutional Class (2.20)% 8.28%*
Russell 2500 Index 0.38% 10.32%

*Commenced operations on June 2, 1997.

EXPENSES AND FEES

INSTITUTIONAL CLASS
-------------------
ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ........................................... 0.80%
Distribution (12b-1) fees ................................. None
Other expenses(1) ......................................... 0.45%
----
Total annual Fund operating expenses .................. 1.25%
Fee waivers(2) ............................................ 0.25%
----
Net expenses .............................................. 1.00%
====

(1) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Institutional Class.

(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.00%.

<PAGE>

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$102 $372 $662 $1,489

<PAGE>

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

MID CAP VALUE FUND
----------------------------------------------------
FOR THE FOR THE FOR THE PERIOD
YEAR ENDED YEAR ENDED JUNE 2, 1997*
AUGUST 31, AUGUST 31, THROUGH AUGUST 31,
1999 1998 1997
------------- ------------- ------------------
INSTITUTIONAL INSTITUTIONAL INSTITUTIONAL
CLASS CLASS CLASS
------------- ------------- ------------------
<S> <C> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ............................. $ 9.48 $ 11.01 $10.00
-------- ------- ------
Net investment income/(loss) (1) ................................. 0.02 0.01 0.01
Net realized and unrealized gain/(loss) on investments (2) ....... 1.98 (1.39) 1.00
-------- ------- ------
Net increase/(decrease) in net assets resulting from operations. . 2.00 (1.38) 1.01
-------- ------- ------
Dividends to shareholders from:
Net investment income ............................................ (0.01) (0.01) --
Net realized capital gains ....................................... -- (0.14) --
-------- ------- ------
Total dividends and distributions to shareholders ................ (0.01) (0.15) --
-------- ------- ------
Net asset value, end of period ................................... $ 11.47 $ 9.48 $11.01
======== ======= ======
Total investment return .......................................... 21.08% (12.73%) 10.10%(3)
======== ======= ======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) ..................... $173,224 $67,568 $3,750
Ratio of expenses to average net assets (1) ................... 1.00% 1.00% 1.00%(4)
Ratio of expenses to average net assets without
waivers and expense reimbursements .......................... 1.25% 1.57% 12.37%(4)
Ratio of net investment income to average net assets (1) ...... 0.17% 0.13% 1.08%(4)
Portfolio turnover rate ....................................... 200.09% 167.86% 21.80%
<FN>
- -------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS SMALL CAP VALUE FUND II
- --------------------------------------------------------------------------------
(formerly, the "Boston Partners Micro Cap Value Fund")
================================================================================
IMPORTANT DEFINITIONS

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

ADRS AND EDRS: Receipts typically issued by a United States bank or trust
company evidencing ownership of underlying foreign securities.
================================================================================

INVESTMENT GOALS

The Fund seeks long-term growth of capital primarily through investment in
equity securities. Current income is a secondary objective.

PRIMARY INVESTMENT STRATEGIES

The Fund pursues its goal by investing, under normal market conditions, at
least 65% of its total assets in a diversified portfolio consisting primarily of
equity securities of issuers with market capitalizations that do not exceed $1
billion when purchased by the Fund and identified by Boston Partners Asset
Management L.P. (the "Adviser") as having value characteristics.

The Fund generally invests in the equity securities of small companies. The
Adviser will seek to invest in companies it considers to be well managed and to
have attractive fundamental financial characteristics. The Adviser believes
greater potential for price appreciation exists among small companies since they
tend to be less widely followed by other securities analysts and thus may be
more likely to be undervalued by the market. The Fund may invest from time to
time a portion of its assets, not to exceed 35% (under normal conditions) at the
time of purchase, in companies with considerably larger market capitalizations.

The Adviser examines various factors in determining the value
characteristics of such issuers including 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 fundamental analysis of industries and companies, earnings power and growth
and other investment criteria.

The Fund may invest up to 25% of its total assets in equity securities of
foreign issuers, including American Depository Receipts ("ADRs") and European
Depository Receipts ("EDRs").

The Fund may participate as a purchaser in any initial public offering of
securities that may trade at a premium in the secondary market when such a
secondary market exists, although it presently has no intention to do so.

14
<PAGE>

KEY RISKS

(BULLET) Investors may lose money.

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

(BULLET) The Fund will invest in smaller issuers which are more volatile
than investments in issuers with a market capitalization greater than $1
billion. Small market capitalization issuers are not as diversified in
their business activities as issuers with market values greater than $1
billion and are more susceptible to changes in the business cycle.

(BULLET) The equity securities in which the Fund invests will often be
traded only in the over-the-counter market or on a regional securities
exchange, may be listed only in the quotation service commonly known as
the "pink sheets," and may not be traded every day or in the volume
typical of trading on a national securities exchange. These equity
securities may also be subject to wide fluctuations in market value. The
trading market for any given equity security may be sufficiently small as
to make it difficult for the Fund to dispose of a substantial block of
such equity securities. The sale by the Fund of portfolio securities to
meet redemptions may require the Fund to sell these securities at a
discount from market prices or during periods when, in the Adviser's
judgement, such sale is not desirable. Moreover, the lack of an efficient
market for these securities may make them difficult to value.

<PAGE>

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Institutional Class of the
Fund. The table is based upon expenses for the Institutional Class of the Fund
for the most recent fiscal year ended August 31, 1999.

INSTITUTIONAL CLASS*
-------------------
SHAREHOLDER FEES (fees paid directly from your investment)
Maximum sales charge imposed on purchases ................. None
Maximum deferred sales charge ............................. None
Maximum sales charge imposed on reinvested dividends ...... None
Redemption Fee(1) ......................................... 1.00%
Exchange Fee .............................................. None

ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ........................................... 1.25%
Distribution (12b-1) fees ................................. None
Other expenses(2) ......................................... 16.59%
-----
Total annual Fund operating expenses .................. 17.84%
Fee waivers and expense reimbursements(3) ................. 16.29%
-----
Net expenses .............................................. 1.55%
=====

* The Fund was renamed the Small Cap Value Fund II on February 18, 2000.

(1) To prevent the Fund from being adversely affected by the transaction
costs associated with short-term shareholder transactions, the Fund
will redeem shares at a price equal to the net asset value of the
shares, less an additional transaction fee equal to 1.00% of the net
asset value of all such shares redeemed that have been held for less
than one year. Such fees are not sales charges or contingent deferred
sales charges, but are retained by the Fund for the benefit of
remaining shareholders.

(2) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Institutional Class.

(3) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.55%.

<PAGE>

EXAMPLE

The example is intended to help you compare the cost of investing in the
Institutional Class of the Fund with the cost of investing in other mutual
funds. The example assumes that you invest $10,000 in the Institutional Class of
the Fund for the time periods indicated and then redeem all of your shares at
the end of each period. The example also assumes that your investment has a 5%
return each year and that the operating expenses of the Institutional Class of
the Fund remain the same, except for the expiration of the fee waivers and
reimbursements on December 31,2000. Although your actual costs may be higher or
lower, based on these assumptions your cost would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$158 $3,390 $5,846 $9,704

<PAGE>

FINANCIAL HIGHLIGHTS

<TABLE>
<CAPTION>
SMALL CAP VALUE FUND II (DAGGER)
-------------------------------------
FOR THE FOR THE PERIOD
YEAR ENDED JULY 1, 1998*
AUGUST 31, THROUGH AUGUST 31,
1999 1998
------------- ------------------
INSTITUTIONAL INSTITUTIONAL
CLASS CLASS
------------- ------------------
<S> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ................................... $ 7.62 $ 10.00
------ -------
Net investment income/(loss) (1) ....................................... (0.01) (0.01)
Net realized and unrealized gain/(loss) on investments (2) ............. 1.06 (2.37)
------ -------
Net increase/(decrease) in net assets resulting from operations. ....... 1.05 (2.38)
------ -------
Dividends to shareholders from:
Net investment income .................................................. -- --
Net realized capital gains ............................................. -- --
------ -------
Total dividends and distributions to shareholders ...................... -- --
------ -------
Net asset value, end of period ......................................... $ 8.67 $ 7.62
====== =======
Total investment return (5) ............................................ 13.78% (23.80%)(3)
====== =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) ........................... $ 1,309 $ 1,120
Ratio of expenses to average net assets (1) ......................... 1.55% 1.55%(4)
Ratio of expenses to average net assets without waivers and
expense reimbursements ............................................ 17.84% 17.63%(4)
Ratio of net investment (loss) to average net assets (1) ............ (0.17%) (0.34%)(4)
Portfolio turnover rate ............................................. 87.48% 11.97%
<FN>
- ------------

(DAGGER) The Fund's name was changed from the Micro Cap Value Fund to the Small
Cap Value Fund II on February 18, 2000.
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
(5) Redemption fee of 1.00% is not reflected in total return calculations.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS BOND FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

TOTAL RETURN: A way of measuring Fund performance. Total return is based on a
calculation that takes into account income dividends, capital gain distributions
and the increase or decrease in share price.

FIXED-INCOME SECURITIES: Fixed-income securities are generally bonds, which are
a type of security that functions like a loan. Bonds are "IOUs" issued by
private companies, municipalities or government agencies. By comparison, when
you buy a stock, you are buying ownership in a company. With a bond, your "loan"
is for a specific period, usually 5 to 30 years. You receive regular interest
payments at a fixed rate. Hence the term "fixed-income" security.

INVESTMENT-GRADE FIXED-INCOME SECURITIES: Securities which are rated at the time
of purchase "AAA," "AA," "A," or "BBB" by S&P, "Aaa," "Aa," "A" or "Baa" by
Moody's or which are similarly rated by another Rating Organization or are
unrated but deemed by the Adviser to be comparable in quality to instruments
that are so rated. Debt securities rated "BBB" by S&P, "Baa" by Moody's or the
equivalent rating of another Rating Organization, while still deemed
investment-grade, are considered to have speculative characteristics and are
more sensitive to economic change than higher rated bonds.

CORPORATE DEBT OBLIGATIONS: A long-term bond issued by a corporation, including
railroads and public utilities.

MORTGAGE-BACKED SECURITIES: Pools of mortgage loans assembled for sale to
investors by various governmental agencies as well as by private issuers.

ASSET-BACKED SECURITIES: Pools of assets, usually loans such as installment sale
contracts or credit card receivables, assembled for sale by private issuers.

MATURITY: The date on which an investor in a fixed income security will be paid
in full by the issuer.
================================================================================

INVESTMENT GOALS

The Fund seeks to maximize total return by investing principally in
investment grade fixed-income securities. Current income is a secondary goal.

PRIMARY INVESTMENT STRATEGIES

The Fund invests (during normal market conditions) at least 75% of its
total assets in bonds, including corporate debt obligations and mortgage-backed
and asset-backed securities (collectively, "Debt Securities") rated
investment-grade or better at the time of purchase by Standard & Poor's Ratings
Group ("S&P") or Moody's Investors Service, Inc. ("Moody's") or which are
similarly rated by another nationally recognized statistical rating organization
("Rating Organization"). The Fund may also purchase Debt Securities which are
unrated but deemed by Boston Partners Asset Management L.P. (the "Adviser") to
be comparable in quality to investment-grade instruments. The Fund may invest up
to 25% of its total assets in Debt Securities rated "Ba" and "B" by Moody's or
"BB" and "B" by S&P or which are similarly rated by another Rating Organization
(i.e., high yield, high risk securities) or are unrated but deemed by the
Adviser to be comparable in quality to instruments that are so rated.

KEY RISKS

(BULLET) The net asset value ("NAV") of the Fund will change with changes
in the market value of its portfolio positions.

(BULLET) Investors may lose money.

(BULLET) The Fund is subject to interest rate risk. Rising interest rates
cause the prices of fixed-income securities to decrease and falling
interest rates cause the prices of fixed-income securities to increase.
Securities with longer maturities can be more sensitive to interest rate
changes. In effect, the longer the maturity of a security, the greater
the impact a change in interest rates could have on the security's price.

(BULLET) High yield, high risk fixed-income securities have a greater risk
of default in the payment of interest and principal than higher rated
securities and are subject to significant changes in price. Investment by
the Fund in such securities involves a high degree of credit risk and
such securities are regarded as speculative by the major rating agencies.

<PAGE>

mance, high portfolio turnover could result in taxable capital gains. The
annual portfolio turnover rate for the Fund is not expected to exceed
100%, however, it may be higher if the Adviser believes it will improve
the Fund's performance.

PRIOR PERFORMANCE

ANNUAL TOTAL RETURNS AS OF DECEMBER 31

[GRAPHIC OMITTED]

EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

1998
----
7.37%

Since inception (December 30, 1997), the highest calendar quarter total
return for the Institutional Class of the Fund was 2.50% (quarter ended
September 30, 1998) and the lowest calendar quarter total return was (.53)%
(quarter ended March 31, 1999). The total return was (.08)% for the nine months
ended September 30, 1999.

<PAGE>

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Institutional
Class, compare with the Lehman Aggregate Index for the same periods. The Lehman
Aggregate Index is an unmanaged index containing fixed-income securities rated
investment grade or higher by Moody's, S&P or Fitch Investors Service. All
issues have at least one year to maturity and an outstanding par value of at
least $100 million. The Lehman Aggregate Index is a registered trademark of
Lehman Brothers, Inc. The table, like the bar chart, provides some indication of
the risks of investing in the Fund by showing how the Fund's average annual
total returns for 1 year and since inception compare with those of a broad
measure of market performance. Past performance is not necessarily an indicator
of how the Fund will perform in the future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------ ---------------
Institutional Class 7.37% 7.44%*
Lehman Aggregate Index 8.69% 8.64%

*Commenced operations on December 30, 1997.

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Institutional Class of the
Fund. The table is based upon expenses for the Institutional Class of the Fund
for the most recent fiscal year ended August 31, 1999.

INSTITUTIONAL CLASS
-------------------
ANNUAL FUND OPERATING EXPENSES (expenses
that are deducted from Fund assets)

Management fees ........................................ 0.40%
Distribution (12b-1) fees .............................. None
Other expenses(1) ...................................... 1.82%
----
Total annual Fund operating expenses ............... 2.22%
Fee waivers and expense reimbursements(2) .............. 1.62%
----
Net expenses ........................................... 0.60%
====

(1) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Institutional Class.

(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual Fund
operating expenses exceed 0.60%.

<PAGE>

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$61 $538 $1,041 $2,427

<PAGE>

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

<TABLE>
<CAPTION>
BOND FUND
----------------------------------
FOR THE FOR THE PERIOD
YEAR ENDED DECEMBER 30, 1997*
AUGUST 31, THROUGH AUGUST 31,
1999 1998
------------- ------------------
INSTITUTIONAL INSTITUTIONAL
CLASS CLASS
------------- ------------------
<S> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ....................................... $ 10.08 $ 10.00
------- -------
Net investment income/(loss) (1). .......................................... 0.96 0.78
Net realized and unrealized gain/(loss) on investments (2) ................. (0.90) (0.31)
------- -------
Net increase/(decrease) in net assets resulting from operations. ........... 0.06 0.47
------- -------
Dividends to shareholders from:
Net investment income. ..................................................... (0.62) (0.39)
Net realized capital gains ................................................. (0.11) --
------- -------
Total dividends and distributions to shareholders .......................... (0.73) (0.39)
------- -------
Net asset value, end of period ............................................. $ 9.41 $ 10.08
======= =======
Total investment return (3) ................................................ 0.42% 4.79%
======= =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted). .............................. $12,041 $15,509
Ratio of expenses to average net assets (1). ............................ 0.60% 0.60%(4)
Ratio of expenses to average net assets without waivers and
expense reimbursements ................................................ 2.22% 2.82%(4)
Ratio of net investment income to average net assets (1) ................ 6.22% 6.06%(4)
Portfolio turnover rate. ................................................ 57.60% 45.27%
<FN>
- ------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS MARKET NEUTRAL FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

MARKET NEUTRAL: Refers to a strategy of investing or engaging in transactions in
equity securities, while seeking to minimize the impact of movements in the
equity markets.

SALOMON SMITH BARNEY U.S. 1-MONTH TREASURY BILL INDEX(TRADE MARK): An unmanaged
index containing monthly return equivalents of yield averages that are not
marked to market.

SHORT SALE: A sale by the Fund of a security which has been borrowed from a
third party on the expectation that the market price will drop. If the price of
the security drops, the Fund will make a profit by purchasing the security in
the open market at a lower price than the one at which it sold the security. If
the price of the security rises, the Fund may have to cover its short position
at a higher price than the short sale price, resulting in a loss.

SHORT-TERM CASH INSTRUMENTS: These temporary investments include notes issued or
guaranteed by the U.S. Government, its agencies or instrumentalities; commercial
paper rated in the two highest rating categories; certificates of deposit;
repurchase agreements and other high-grade corporate debt securities.

FEDERAL FUNDS RATE: The rate of interest charged by a Federal Reserve bank for
member banks to borrow their federally required reserve.

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

ADRS: Receipts typically issued by a United States bank or trust company
evidencing ownership of underlying foreign securities.
================================================================================

INVESTMENT GOALS

The Fund seeks long-term capital appreciation while minimizing exposure to
general equity market risk. The Fund seeks a total return greater than that of
the Salomon Smith Barney U.S. 1-Month Treasury Bill Index.(TRADE MARK)

PRIMARY INVESTMENT STRATEGIES

The Fund invests in long positions in stocks identified by Boston Partners
Asset Management L.P. (the "Adviser") as undervalued and short positions in
stocks that the Adviser has identified as overvalued. The cash proceeds from
short sales will be invested in short-term cash instruments to produce a return
on such proceeds just below the federal funds rate. The Fund will invest in
securities principally traded in the United States markets. The Adviser will
determine the size of each long or short position by analyzing the tradeoff
between the attractiveness of each position and its impact on the risk of the
overall portfolio. The Fund seeks to construct a portfolio that has minimal net
exposure to the United States equity market generally and low to neutral
exposure to specific industries, specific market capitalization ranges (e.g.,
large cap, mid cap and small cap) and certain other factors.

The Fund's long and short positions may involve (without limit) equity
securities of foreign issuers that are traded in the markets of the United
States as sponsored American Depository Receipts ("ADRs"). The Fund may also
invest up to 20% of its total assets directly in equity securities of foreign
issuers.

To meet margin requirements, redemptions or pending investments, the Fund
may also temporarily hold a portion of its assets in full faith and credit
obligations of the United States government and in short-term notes, commercial
paper or other money market instruments.

<PAGE>

KEY RISKS

(BULLET) The net asset value ("NAV") of the Fund will change with changes
in the market value of its portfolio positions.

(BULLET) Investors may lose money.

(BULLET) The Fund is subject to the risk of poor stock selection by the
Adviser. In other words, the Adviser may not be successful in its
strategy of taking long positions in undervalued stocks and short
positions in overvalued stocks. Further, since the Adviser will manage
both a long and a short portfolio, there is the risk that the Adviser may
make more poor investment decisions than an adviser of a typical stock
mutual fund with only a long portfolio may make.

(BULLET) Short sales of securities may result in gains if a security's
price declines, but may result in losses if a security's price does not
decline in price.

(BULLET) The Fund could lose money if a seller under a repurchase agreement
defaults or declares bankruptcy.

(BULLET) Securities held in a segregated account cannot be sold while the
position it is covering is outstanding, unless they are replaced with
similar securities. As a result, there is a possibility that segregation
of a large percentage of the Fund's assets could impede portfolio
management or the Fund's ability to meet redemption requests or other
current obligations.

(BULLET) The Fund may, for temporary defensive purposes, invest a
percentage of its total assets, without limitations, in cash or various
U.S. dollar-denominated money market instruments. The value of money
market instruments tends to fall when current interest rates rise. Money
market instruments are generally less sensitive to interest rate changes
than longer-term securities. When the Fund's assets are invested in these
instruments, the Fund may not be achieving its investment objective.

(BULLET) The risks of international investing include, but are not limited
to, currency exchange rate volatility, political, social or economic
instability, and differences in taxation, auditing and other financial
practices.

(BULLET) If the Fund frequently trades its portfolio securities, the Fund
will incur higher brokerage commissions and transaction costs, which
could lower the Fund's performance. In addition to lower performance,
high portfolio turnover could result in taxable capital gains. The annual
portfolio turnover rate for the Fund is not expected to exceed 200%,
however, it may be higher if the Adviser believes it will improve the
Fund's performance.

EXPENSES AND FEES

<PAGE>

INSTITUTIONAL CLASS
-------------------
SHAREHOLDER FEES (fees paid directly
from your investment)

Maximum sales charge imposed on purchases .............. None
Maximum deferred sales charge .......................... None
Maximum sales charge imposed on reinvested dividends ... None
Redemption Fee(1) ...................................... 1.00%
Exchange Fee ........................................... None

ANNUAL FUND OPERATING EXPENSES (expenses that
are deducted from Fund assets)

Management fees ........................................ 2.25%
Distribution (12b-1) fees .............................. None
Other expenses(2) ...................................... 24.11%
-----
Total annual Fund operating expenses ............... 26.36%
Fee waivers and expense reimbursements(3) .............. 23.41%
-----
Net expenses ........................................... 2.95%
=====

(2) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Institutional Class. "Other expenses" and "Total annual Fund operating
expenses" include dividends on securities which the Fund has sold short
("short-sale dividends"). Short-sale dividends generally reduce the
market value of the securities by the amount of the dividend declared
-- thus increasing the Fund's unrealized gain or reducing the Fund's
unrealized loss on the securities sold short. Short-sale dividends are
treated as an expense, and increase the Fund's total expense ratio,
although no cash is received or paid by the Fund. The amount of
short-sale dividends is estimated at 0.45% of average net assets for
the current fiscal year.

(3) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 2.50% excluding short sale dividend
expense.

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$298 $4,590 $7,245 $10,253

<PAGE>

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

The table below sets forth certain financial information for the periods
indicated, including per share information results for a single Fund share. The
term "Total Return" indicates how much your investment would have increased or
decreased during this period of time and assumes that you have reinvested all
dividends and distributions. This information has been derived from the Fund's
financial statements audited by PricewaterhouseCoopers LLP, the Company's
independent accountants. This information should be read in conjunction with the
Fund's financial statements which, together with the report of independent
accountants, are included in the Fund's annual report, which is available upon
request (see back cover for ordering instructions).
MARKET NEUTRAL FUND
-------------------
FOR THE PERIOD
NOVEMBER 17, 1998*
THROUGH AUGUST 31,
1999
-------------------
INSTITUTIONAL CLASS
-------------------
Per Share Operating Performance**
Net asset value, beginning of period .................. $ 10.00
-------
Net investment income/(loss) (1) ...................... 0.12
Net realized and unrealized gain/(loss)
on investments (2) ................................. (0.66)
-------
Net increase/(decrease) in net assets
resulting from operations .......................... (0.54)
-------
Dividends to shareholders from:
Net investment income ................................. --
Net realized capital gains ............................ --
-------
Total dividends and distributions to shareholders ..... --
-------
Net asset value, end of period ........................ $ 9.46
=======
Total investment return (3) (5) ....................... (5.40%)
=======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) .......... $ 941
Ratio of expenses to average net assets (1) ........ 2.50%(4)(6)
Ratio of expenses to average net assets
without waivers and expense reimbursements ...... 26.36%(4)(6)
Ratio of net investment income to
average net assets (1) .......................... 1.57%(4)
Portfolio turnover rate ............................ 218.41%
- ------------
* Commencement of operations.

** Calculated based on shares outstanding on the sfirst and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.

(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 not annualized.
(4) Annualized.
(5) Redemption fee of 1.00% is not reflected in total return calculations.
(6) Without the voluntary waiver of advisory and administration fees, the ratios
of expenses to average net assets for the Institutional Class would have
been 26.36% (excluding dividend expense) and 26.77% (including dividend
expense) annualized for the period ended August 31, 1999.

<PAGE>

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

INVESTMENT ADVISER

Boston Partners Asset Management, L.P. (the "Adviser"), located at 28 State
Street, 21st Floor, Boston, Massachusetts 02109, provides investment advisory
services to the Funds. The Adviser provides investment management and investment
advisory services to investment companies and other institutional accounts. As
of October, 1999, the Adviser managed approximately $10.2 billion in assets. The
Adviser is organized as a Delaware limited partnership whose sole general
partner is Boston Partners, Inc., a Delaware corporation. The Adviser manages
each Fund's business and investment activities subject to the authority of the
Company's Board of Directors.

PORTFOLIO MANAGERS

BOSTON PARTNERS LARGE CAP VALUE FUND

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 $5.5 billion in large
cap value institutional equity assets. Prior to joining the Adviser in 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 ("CFA") and has over fifteen years of investment experience.
Ms. Sharp is Vice Chairperson of the Adviser's Equity Strategy Committee and has
over twenty-one years of investment experience. Prior to joining the Adviser in
April 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 CFA. For the fiscal year ended August 31, 1999, the Fund paid .60% (expressed
as a percentage of average net assets) to the Adviser for its services.

BOSTON PARTNERS MID CAP VALUE FUND

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 $1.5 billion in mid-capitalization activities as
well as $1 billion in small capitalization activities. Prior to joining the
Adviser in April 1995, Mr. Archambo was employed by The Boston Company Asset
Management, Inc. from 1989 through April 1995 where he was a senior portfolio
manager. Mr. Archambo has over 15 years of investment experience and is a CFA.
For the fiscal year ended August 31, 1999, the Fund paid .70% (expressed as a
percentage of average net assets) to the Adviser for its services.

BOSTON PARTNERS SMALL CAP VALUE FUND II

The day-to-day portfolio management of the Fund is the responsibility of
David M. Dabora and Wayne J. Archambo who are senior portfolio managers of the
Adviser. Prior to taking on day to day responsibilities for the Small Cap Value
Fund II, Mr. Dabora was an assistant portfolio manager/analyst of the premium
equity product of the Adviser, an all-cap value institutional product. Before
joining the Adviser in April 1995, Mr. Dabora had been employed by The Boston
Company Asset Management, Inc. since 1991 as a senior equity analyst. Mr. Dabora
has over 11 years of investment experience and is a CFA. For the fiscal year
ended August 31, 1999, the Fund paid 0% (expressed as a percentage of average
net assets) to the Adviser for its services.

<PAGE>

BOSTON PARTNERS BOND FUND

The day-to-day portfolio management of the Fund is the responsibility of
William R. Leach who is a senior portfolio manager of the Adviser and Chairman
of the Fixed Income Strategy Committee. Prior to joining the Adviser in April
1995, Mr. Leach was employed by The Boston Company Asset Management, Inc. from
1988 through April 1995 where he was a senior portfolio manager and Director of
the Fixed Income Strategy Committee. Mr. Leach has over 16 years of investment
experience and is a CFA. Mr. Leach will be assisted by Glenn S. Davis, Joseph F.
Feeney, Jr. and Michael A. Mullaney. Mr. Davis is a Fixed Income Portfolio
Manager with the Adviser and is also a CFA. Prior to joining the Adviser in
April 1995, he was Vice President and Portfolio Manager at The Boston Company,
specializing in short and intermediate term corporate bonds. Prior to that
position, he was responsible for the Short-term Fixed Income Group at State
Street Global Advisors. He has a total of 17 years of investment experience. Mr.
Feeney is a Fixed Income Portfolio Manager with the Adviser and also a CFA.
Prior to joining the Adviser in April 1995, he was Assistant Vice President and
Mortgage-backed Securities Portfolio Manager for Putnam Investments. Mr.
Mullaney is a Fixed Income Portfolio Manager who joined the Adviser in June
1997. From 1984 to 1997, he was employed at Putnam Investments, most recently as
Managing Director and Senior Investment Strategist, specializing in portfolio
strategy and management. His prior experience included a position as a senior
Consultant from 1981 to 1983 with Chase Econometrics/Interactive Data
Corporation, where he focused on quantitative methodologies in fixed income and
equity management. He has over 16 years of investment experience. For the fiscal
year ended August 31, 1999, the Fund paid 0% (expressed as a percentage of
average net assets) to the Adviser for its services.

BOSTON PARTNERS MARKET NEUTRAL FUND

The day-to-day portfolio management of the Fund is the responsibility of
Edmund D. Kellogg, subject to the supervision of Harry J. Rosenbluth. Both Mr.
Kellogg and Mr. Rosenbluth are portfolio managers employed by the Adviser.
Previously, Mr. Kellogg was a portfolio manager/analyst for a similar limited
partnership private investment fund and a separate account of the Adviser.
Before joining the Adviser in 1996, Mr. Kellogg was employed by The Keystone
Group since 1991, where he was a portfolio manager and analyst managing
institutional separate accounts. Mr. Kellogg has over 21 years of investment
experience and is a CFA. Mr. Rosenbluth oversees other institutional accounts of
the Adviser and manages a $2.2 billion all-capitalization value equity
institutional separate account product. Prior to joining the Adviser in 1995,
Mr. Rosenbluth was employed by The Boston Company Asset Management, Inc. since
1981 as a senior portfolio manager. Mr. Rosenbluth has over 17 years of
investment experience and is a CFA. For the period ended August 31, 1999, the
Boston Partners Market Neutral Fund paid 0% (expressed as a percentage of
average net assets) to the Adviser for its services.

OTHER SERVICE PROVIDERS

The following chart shows the Funds' other service providers and includes
their addresses and principal activities.

<PAGE>

------------
SHAREHOLDERS
------------

Distribution and
Shareholder Services

------------------------------------ -----------------------------------------
PRINCIPAL DISTRIBUTOR TRANSFER AGENT AND DIVIDEND
DISBURSING AGENT
PROVIDENT DISTRIBUTORS, INC.
3200 HORIZON DRIVE PFPC INC.
KING OF PRUSSIA, PA 19406 400 BELLEVUE PARKWAY
WILMINGTON, DE 19809
Distributes shares of the
BOSTON PARTNERS Funds. Handles shareholder services,
including recordkeeping and statements,
distribution of dividends and processing
of buy, sell and exchange requests.

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

Asset
Management

------------------------------------ -----------------------------------------
INVESTMENT ADVISER CUSTODIAN

BOSTON PARTNER ASSET PFPC TRUST COMPANY
MANAGEMENT, L.P. 200 STEVENS DRIVE
28 STATE STREET 21ST FLOOR LESTER, PA 19113
BOSTON, MA 02109

Holds each Fund's assets, settles
Manages each Fund's business all portfolio trades and collects
and investment activities. most of the valuation data
required for calculating each
Fund's net asset value ("NAV").

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

Fund
Operations

------------------------------------
ADMINISTRATOR

PFPC INC.
400 BELLEVUE PARKWAY
WILMINGTON, DE 19809

Provides facilities, equipment
and personnel to carry out
administrative services related
to each Fund and calculates each
Fund's NAV, dividends
and distributions.
------------------------------------

---------------------------------
BOARD OF DIRECTORS

Supervises the Funds' activities.
---------------------------------

<PAGE>

SHAREHOLDER INFORMATION
- --------------------------------------------------------------------------------

PRICING OF FUND SHARES

Institutional Shares of the Funds ("Shares") are priced at their net asset
value ("NAV"). The NAV for the Institutional Class of each Fund is calculated by
adding the value of all securities, cash and other assets in a Fund's portfolio,
deducting the Fund's actual and accrued liabilities and dividing by the total
number of Shares outstanding.

Each Fund's NAV is calculated once daily at the close of regular trading on
the New York Stock Exchange ("NYSE") (currently 4:00 p.m. Eastern time) each day
the NYSE is open. Shares will not be priced on the days on which the NYSE is
closed.

Securities held by a Fund are valued using the closing price or the last
sale price on a national securities exchange or on the NASDAQ National Market
System where they are traded. If there were no sales on that day or the
securities are traded on other over-the-counter markets, the mean of the bid and
asked prices is used. Short-term debt investments having maturities of 60 days
or less are amortized to maturity based on their cost. With the approval of the
Company's Board of Directors, a Fund may use a pricing service, bank or
broker-dealer experienced in providing valuations to value a Fund's securities.
If market quotations are unavailable, securities will be valued at fair value as
determined in good faith by the investment adviser according to procedures
adopted by the Company's Board of Directors.

PURCHASE OF FUND SHARES

Shares representing interests in the Funds are offered continuously for
sale by Provident Distributors, Inc. (the "Distributor"). You may purchase
Shares of each Fund at the NAV per share next calculated after your order is
received by PFPC Inc. (the "Transfer Agent") in proper form as described below.
After an initial purchase is made, the Transfer Agent will set up an account for
you on RBB's records. The minimum initial investment in any Fund is $100,000 and
the minimum additional investment is $5,000. For purposes of meeting the minimum
initial purchase, purchases by clients which are part of endowments, foundations
or other related groups may be combined. You can only purchase Shares of each
Fund on days the NYSE is open and through the means described below. Shares may
be purchased by principals and employees of the Adviser and by their spouses and
children either directly or through any trust that has the principal, employee,
spouse or child as the primary beneficiaries, their individual retirement
accounts, or any pension and profit-sharing plan of the Adviser without being
subject to the minimum investment limitations.

INITIAL INVESTMENT BY MAIL. An account may be opened by completing and
signing the application included with this Prospectus and mailing it to the
Transfer Agent at the address noted below, together with a check ($100,000
minimum) payable to the Fund in which you would like to invest. Third party
checks will not be accepted.

BOSTON PARTNERS [NAME OF FUND]
c/o PFPC Inc.
P.O. Box 8852
Wilmington, DE 19899-8852

The name of the Fund to be purchased should be designated on the
application and should appear on the check. Payment for the purchase of Shares
received by mail will be credited to a shareholder's account at the NAV per
share of the Fund next determined after receipt of payment in good order.

<PAGE>

INITIAL INVESTMENT BY WIRE. Shares of each Fund may be purchased by wiring
federal funds to PNC Bank (see instructions below). A completed application must
be forwarded to the Transfer Agent at the address noted above under "Initial
Investment by Mail" in advance of the wire. For each Fund, notification must be
given to the Transfer Agent at (888) 261-4073 prior to 4:00 p.m., Eastern time,
on the wire date. (Prior notification must also be received from investors with
existing accounts.) Funds should be wired to:

PNC Bank, NA
Philadelphia, Pennsylvania 19103
ABA# 0310-0005-3
Account # 86-1108-2507
F/B/O BOSTON PARTNERS [NAME OF FUND]
Ref. (Account Number)

Federal funds purchases will be accepted only on a day on which the NYSE
and PNC Bank, NA are open for business.

ADDITIONAL INVESTMENTS. Additional investments may be made at any time
(minimum investment $5,000) by purchasing Shares of any Fund at NAV by mailing a
check to the Transfer Agent at the address noted above under "Initial Investment
by Mail" (payable to Boston Partners [name of Fund]) or by wiring monies to PNC
Bank, NA as outlined above under "Initial Investment by Wire." For each Fund,
notification must be given to the Transfer Agent at (888) 261-4073 prior to 4:00
p.m., Eastern time, on the wire date. Initial and additional purchases made by
check cannot be redeemed until payment of the purchase has been collected.

AUTOMATIC INVESTMENT PLAN. Additional investments in Shares of the Funds
may be made automatically by authorizing the Transfer Agent to withdraw funds
from your bank account through an Automatic Investment Plan ($5,000 minimum).
Investors desiring to participate in an Automatic Investment Plan should call
the Transfer Agent at (888) 261-4073 to obtain the appropriate forms.

OTHER PURCHASE INFORMATION. The Company reserves the right, in its sole
discretion, to suspend the offering of Shares or to reject purchase orders when,
in the judgment of management, such suspension or rejection is in the best
interests of the Funds. As of the date of this Prospectus, the Boston Partners
Small Cap Value Fund II intends to suspend the offering of Shares upon the
Fund's attaining $500 million in total assets.

REDEMPTION OF FUND SHARES

You may redeem Shares of the Funds at the next NAV calculated after a
redemption request is received by the Transfer Agent in proper form. You can
only redeem Shares on days the NYSE is open and through the means described
below.

You may redeem Shares of each Fund by mail, or, if you are authorized, by
telephone. The value of Shares redeemed may be more or less than the purchase
price, depending on the market value of the investment securities held by a
Fund. There is no charge for a redemption. However, if a shareholder of the
Boston Partners Small Cap Value Fund II or Boston Partners Market Neutral Fund
redeems Shares held for less than 1 year, a transaction fee of 1% of the net
asset value of the Shares redeemed at the time of redemption will be charged.
For purposes of this redemption feature, shares purchased first will be
considered to be shares first redeemed.

<PAGE>

REDEMPTION BY MAIL. Your redemption requests should be addressed to BOSTON
PARTNERS [name of Fund], c/o PFPC Inc., P.O. Box 8852, Wilmington, DE 19899-8852
and must include:

a. a letter of instruction specifying the number of shares or dollar
amount to be redeemed, signed by all registered owners of the shares in
the exact names in which they are registered;

b. any required signature guarantees, which are required when (i) the
redemption request proceeds are to be sent to someone other than the
registered shareholder(s) or (ii) the redemption request is for $10,000
or more. 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 Agent Medallion Program (STAMP), Stock
Exchanges Medallion Program (SEMP) and New York Stock Exchange, Inc.
Medallion Program (MSP). Signature Guarantees, which are not a part of
these programs, will not be accepted. Please note that a notary public
stamp or seal is not acceptable; and

c. other supporting legal documents, if required, in the case of estates,
trusts, guardianships, custodianships, corporations, pension and profit
sharing plans and other organizations.

REDEMPTION BY TELEPHONE. In order to request a telephone redemption, you
must have returned your account application containing a telephone election. To
add a telephone redemption option to an existing account, contact the Transfer
Agent by calling (888) 261-4073 for a Telephone Authorization Form.

Once you are authorized to utilize the telephone redemption option, a
redemption of Shares may be requested by calling the Transfer Agent at (888)
261-4073 and requesting that the redemption proceeds be mailed to the primary
registration address or wired per the authorized instructions. If the telephone
redemption option or the telephone exchange option (as described below) is
authorized, the Transfer Agent may act on telephone instructions from any person
representing himself or herself to be a shareholder and believed by the Transfer
Agent to be genuine. The Transfer Agent's records of such instructions are
binding and shareholders, not the Company or the Transfer Agent, bear the risk
of loss in the event of unauthorized instructions reasonably believed by the
Company or the Transfer Agent to be genuine. The Transfer Agent will employ
reasonable procedures to confirm that instructions communicated are genuine and,
if it does not, it may be liable for any losses due to unauthorized or
fraudulent instructions. The procedures employed by the Transfer Agent in
connection with transactions initiated by telephone include tape recording of
telephone instructions and requiring some form of personal identification prior
to acting upon instructions received by telephone.

TRANSACTION FEE ON CERTAIN REDEMPTIONS OF THE BOSTON PARTNERS SMALL CAP
VALUE FUND II AND BOSTON PARTNERS MARKET NEUTRAL FUND

The Boston Partners Small Cap Value Fund II and Boston Partners Market
Neutral Fund require the payment of a transaction fee on redemptions of Shares
held for less than one year equal to 1.00% of the net asset value of such Shares
redeemed at the time of redemption. This additional transaction fee is paid to
each Fund, NOT to the adviser, distributor or transfer agent. It is NOT a sales
charge or a contingent deferred sales charge. The fee does not apply to redeemed
Shares that were purchased through reinvested dividends or capital gain
distributions. The purpose of the additional transaction fee is to indirectly
allocate transaction costs associated with redemptions to those investors making
redemptions after holding their shares for a short period, thus protecting
existing shareholders. These costs include: (1) brokerage costs; (2) market
impact costs -- i.e., the decrease in market prices which may result when a Fund
sells certain securities in order to raise cash to meet the redemption request;
(3) the realization of capital gains by the other shareholders in each Fund; and
(4) the effect of the "bid-ask" spread in the over-the-counter market. The 1.00%
amount represents each Fund's estimate of the brokerage and other transaction
costs which may be incurred by each Fund in disposing of stocks in which each
Fund may invest. Without the additional transaction fee, each Fund would
generally be selling its shares at a price less than the cost to each Fund of
acquiring the portfolio securities

<PAGE>

necessary to maintain its investment characteristics, resulting in reduced
investment performance for all shareholders in the Funds. With the additional
transaction fee, the transaction costs of selling additional stocks are not
borne by all existing shareholders, but the source of funds for these costs is
the transaction fee paid by those investors making redemptions of the Boston
Partners Small Cap Value Fund II and Boston Partners Market Neutral Fund.

INVOLUNTARY REDEMPTION. The Company reserves the right to redeem a
shareholder's account in any Fund at any time the net asset value of the account
in such Fund 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 in a Fund is less than $500 and will be allowed 30 days to make
additional investments before the redemption is processed. The transaction fee
applicable to the Boston Partners Small Cap Value Fund II and Boston Partners
Market Neutral Fund will not be charged when shares are involuntarily redeemed.

OTHER REDEMPTION INFORMATION. Redemption proceeds for Shares of the Funds
recently purchased by check may not be distributed until payment for the
purchase has been collected, which may take up to fifteen days from the purchase
date. Shareholders can avoid this delay by utilizing the wire purchase option.

Other than as described above, payment of the redemption proceeds will be
made within seven days after receipt of an order for a redemption. The Company
may suspend the right of redemption or postpone the date at times when the NYSE
is closed or under any emergency circumstances as determined by the SEC.

If the Board of Directors determines that it would be detrimental to the
best interests of the remaining shareholders of the Funds to make payment wholly
or partly in cash, redemption proceeds may be paid in whole or in part by an
in-kind distribution of readily marketable securities held by a Fund instead of
cash in conformity with applicable rules of the SEC. Investors generally will
incur brokerage charges on the sale of portfolio securities so received in
payment of redemptions. The Funds have elected, however, to be governed by Rule
18f-1 under the 1940 Act, so that a Fund 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 Fund.

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 Institutional Shares of any Boston Partners Fund for Institutional
Shares of another Boston Partners Fund, up to six (6) times per year. Such
exchange will be effected at the net asset value of the exchanged Institutional
Shares and the net asset value of the Institutional Shares to be acquired next
determined after PFPC's receipt of a request for an exchange. An exchange of
Boston Partners Small Cap Value Fund II or Boston Partners Market Neutral Fund
Shares held for less than 1 year (with the exception of Shares purchased through
dividend reinvestment or the reinvestment of capital gains) will be subject to
the 1.00% transaction fee. An exchange of Shares will be treated as a sale for
federal income tax purposes. A shareholder may make an exchange by sending a
written request to the Transfer Agent or, if authorized, by telephone (see
"Redemption by Telephone" above).

If the exchanging shareholder does not currently own Institutional Shares
of the Fund whose Shares are being acquired, 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. See "Redemption By Mail" for
information on signature guarantees. The exchange privilege may be modified or
terminated at any time, or from time to time, by the Company, upon 60 days'
written notice to shareholders.

If an exchange is to a new account in a Fund advised by the Adviser, the
dollar value of the Shares acquired must equal or exceed the Fund's minimum for
a new account; if to an existing account, the dollar value must equal or exceed
the Fund's minimum for additional investments. If an amount remains in the Fund
from which the exchange is being made that is below the minimum account value
required, the account will be subject to involuntary redemption.

<PAGE>

The Funds' 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 transaction costs, the Funds have
established a policy of limiting excessive exchange activity. Shareholders are
entitled to six (6) exchange redemptions (at least 30 days apart) from each Fund
during any twelve-month period. Notwithstanding these limitations, the Funds
reserve the right to reject any purchase request (including exchange purchases
from other Boston Partners Funds) that is deemed to be disruptive to efficient
portfolio management.

DIVIDENDS AND DISTRIBUTIONS

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

Each Fund will declare and pay dividends from net investment income
annually, except the Boston Partners Bond Fund, which will declare and pay
dividends from net investment income monthly. Net realized capital gains
(including net short-term capital gains), if any, will be distributed by the
Funds at least annually.

TAXES

Each Fund contemplates declaring as dividends each year all or
substantially all of its taxable income, including its net capital gain (the
excess of long-term capital gain over short-term capital loss). Distributions
attributable to the net capital gain of a Fund will be taxable to you as
long-term capital gain, regardless of how long you have held your Shares. Other
Fund distributions will generally be taxable as ordinary income. You will be
subject to income tax on Fund distributions regardless whether they are paid in
cash or reinvested in additional Shares. You will be notified annually of the
tax status of distributions to you.

You should note that if you purchase Shares just before a distribution, the
purchase price will reflect the amount of the upcoming distribution, but you
will be taxable on the entire amount of the distribution received, even though,
as an economic matter, the distribution simply constitutes a return of a portion
of your purchase price. This is known as "buying into a dividend."

You will recognize taxable gain or loss on a sale, exchange or redemption
of your Shares, including an exchange for Shares of another Fund, based on the
difference between your tax basis in the Shares and the amount you receive for
them. (To aid in computing your tax basis, you generally should retain your
account statements for the periods during which you held Shares.)

Any loss realized on Shares held for six months or less will be treated as
a long-term capital loss to the extent of any capital gain dividends that were
received on the Shares.

The one major exception to these tax principles is that distributions on,
and sales, exchanges and redemptions of, Shares held in an IRA (or other
tax-qualified plan) will not be currently taxable.

Shareowners may also be subject to state and local taxes on distributions
and redemptions. State income taxes may not apply however, to the portions of
each Fund's distributions, if any, that are attributable to interest on federal
securities or interest on securities of the particular state or localities
within the state. Shareowners should consult their tax advisers regarding the
tax status of distributions in their state and locality.

The foregoing is only a summary of certain tax considerations under current
law, which may be subject to change in the future. Shareholders who are
nonresident aliens, foreign trusts or estates, or foreign corporations or
partnerships, may be subject to different United States federal income tax
treatment. You should consult your tax adviser for further information regarding
federal, state, local and/or foreign tax consequences relevant to your specific
situation.

<PAGE>

MULTI-CLASS STRUCTURE

Each Fund also offers Investor Shares, which are offered directly to
individual investors in a separate prospectus. Shares of each class of the Funds
represent equal pro rata interests and accrue dividends and calculate net asset
value and performance quotations in the same manner. The performance of each
class is quoted separately due to different actual expenses. The total return on
Institutional Shares of a Fund can be expected to differ from the total return
on Investor Shares of the same Fund. Information concerning Investor class
shares of the Funds can be requested by calling the Fund at (888) 261-4073.

<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 REPRESENTATIONS
MUST NOT BE 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.

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

CUSTODIAN
PFPC Trust Company
Lester, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

DISTRIBUTOR
Provident Distributors,Inc.
King of Prussia, Pennsylvania

COUNSEL
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

INDEPENDENT ACCOUNTANTS
PricewaterhouseCoopers LLP
Philadelphia, Pennsylvania

<PAGE>

(THIS PAGE INTENTIONALLY LEFT BLANK.)

<PAGE>

BOSTON PARTNERS FAMILY OF FUNDS
OF
THE RBB FUND, INC.
(888) 261-4073
HTTP://WWW.BOSTONPARTNERSFUNDS.COM

FOR MORE INFORMATION:

This prospectus contains important information you should know before you
invest. Read it carefully and keep it for future reference. More information
about the BOSTON PARTNERS FAMILY OF FUNDS is available free, upon request,
including:

ANNUAL/SEMI-ANNUAL REPORT

These reports contain additional information about each of the Fund's
investments, describe each of the Fund's performance, list portfolio holdings,
and discuss recent market conditions and economic trends. The annual report
includes fund strategies that significantly affected the Funds' performance
during their last fiscal year.

STATEMENT OF ADDITIONAL INFORMATION (SAI)

A Statement of Additional Information, dated December 1, 1999 (SAI), has
been filed with the Securities and Exchange Commission. The SAI, which includes
additional information about the BOSTON PARTNERS FAMILY OF FUNDS, may be
obtained free of charge, along with the annual and semi-annual reports, by
calling (888) 261-4073. The SAI, as supplemented from time to time, is
incorporated by reference into this Prospectus.

SHAREHOLDER INQUIRIES

Representatives are available to discuss account balance information,
mutual fund prospectuses, literature, programs and services available. Hours: 8
a.m. to 6 p.m. (Eastern time) Monday-Friday. Call: (888) 261-4073 or visit the
website of Boston Partners Asset Management L.P. at
http://www.bostonpartnersfunds.com.

PURCHASES AND REDEMPTIONS

Call (888) 261-4073.

WRITTEN CORRESPONDENCE

Post Office Address: BOSTON PARTNERS FAMILY OF FUNDS, c/o PFPC, Inc. PO Box
8852, Wilmington, DE 19899-8852

Street Address: BOSTON PARTNERS FAMILY OF FUNDS, c/o PFPC, Inc. 400
Bellevue Parkway, Wilmington, DE 19809

SECURITIES AND EXCHANGE COMMISSION (SEC)

You may also view information about The RBB Fund, Inc. and the BOSTON
PARTNERS FAMILY OF FUNDS, including the SAI, by visiting the SEC website
(http://www.sec.gov) or the SEC's Public Reference Room in Washington, D.C.
Information about the operation of the public reference room can be obtained by
calling the SEC directly at 1-202-942-8090. Copies of this information can be
obtained, for a duplicating fee, by writing to the Public Reference Section of
the SEC, Washington, D.C. 20549-0102, or by electronic request to
[email protected].

INVESTMENT COMPANY ACT FILE NO. 811-05518
<PAGE>
PROSPECTUS

DECEMBER 1, 1999
(as revised March 28, 2000)

BOSTON PARTNERS
LARGE CAP VALUE FUND

BOSTON PARTNERS
MID CAP VALUE FUND

BOSTON PARTNERS
SMALL CAP VALUE FUND II

BOSTON PARTNERS
BOND FUND

BOSTON PARTNERS
MARKET NEUTRAL FUND
INVESTOR CLASS

[GRAPHIC OMITTED]
bp
BOSTON PARTNERS ASSET MANAGEMENT,L.P.
- -------------------------------------

<PAGE>

BOSTON PARTNERS FAMILY OF FUNDS
OF
THE RBB FUND, INC.

INVESTOR CLASS

BOSTON PARTNERS FAMILY OF FUNDS
LARGE CAP VALUE FUND
MID CAP VALUE FUND
SMALL CAP VALUE FUND II
BOND FUND
MARKET NEUTRAL FUND

TABLE OF CONTENTS
- --------------------------------------------------------------------------------

================================= INTRODUCTION ...............................3

DESCRIPTIONS OF THE BOSTON PARTNERS FUNDS

A LOOK AT THE GOALS, STRATEGIES, Boston Partners Large Cap Value Fund ....4
RISKS, EXPENSES AND FINANCIAL
HISTORY OF EACH OF THE Boston Partners Mid Cap Value Fund ......9
BOSTON PARTNERS FUNDS.
Boston Partners Small Cap Value Fund II.13

Boston Partners Bond Fund ..............17

Boston Partners Market Neutral Fund ....21

MANAGEMENT

DETAILS ABOUT THE SERVICE Investment Adviser .....................25
PROVIDERS.
Service Provider Chart .................27

SHAREHOLDER INFORMATION

POLICIES AND INSTRUCTIONS FOR Pricing of Fund Shares .................28
OPENING, MAINTAINING AND
CLOSING AN ACCOUNT IN ANY OF Purchase of Fund Shares ................28
THE BOSTON PARTNERS FUNDS.
Redemption of Fund Shares ..............30

Exchange Privilege .....................32

Dividends and Distributions ............33

Taxes ..................................33

Multi-Class Structure ..................34

================================= FOR MORE INFORMATION ..............Back Cover

2
<PAGE>

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

This Prospectus has been written to provide you with the information you
need to make an informed decision about whether to invest in the Investor Class
of the Boston Partners Family of Funds of The RBB Fund, Inc. (the "Company").

The five mutual funds of the Company offered by this Prospectus represent
interests in the Boston Partners Large Cap Value Fund, Boston Partners Mid Cap
Value Fund, Boston Partners Micro Cap Value Fund, Boston Partners Bond Fund, and
Boston Partners Market Neutral Fund (each a "Fund" and collectively, the
"Funds"). This Prospectus and the Statement of Additional Information
incorporated herein relate solely to the Funds.

<PAGE>

BOSTON PARTNERS LARGE CAP VALUE FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

INVESTMENT GOALS

The Fund seeks to provide long-term growth of capital with current income
as a secondary objective.

PRIMARY INVESTMENT STRATEGIES

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.

KEY RISKS

(BULLET) Investors may lose money.

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

<PAGE>

tends to fall when current interest rates rise. Money market instruments
are generally less sensitive to interest rate changes than longer-term
securities. When the Fund's assets are invested in these instruments, the
Fund may not be achieving its investment objective.

PRIOR PERFORMANCE

ANNUAL TOTAL RETURNS AS OF DECEMBER 31

The bar chart below shows the variability of the annual total returns for
the Investor Class of the Fund for the last two calendar years. The bar chart
provides some indication of the risks of investing in the Fund by showing
changes in the performance of the Fund's Investor Class from year to year. Past
performance is not necessarily an indicator of how the Fund will perform in the
future.

[GRAPHIC OMITTED]
EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

1997 1998
------ -------
28.34% (0.77%)

Since inception (January 16, 1997), the highest calendar quarter total
return for the Investor Class of the Fund was 15.30% (quarter ended June 30,
1998) and the lowest calendar quarter total return was (16.07)% (quarter ended
September 30, 1998). The total return was (10.98)% for the calendar nine months
ended September 30, 1999.

<PAGE>

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Investor Class,
compare with the Standard & Poor's 500 Composite Stock Price Index (the "S&P 500
Index") for the same periods. The S&P 500 Index is an unmanaged index composed
of 500 common stocks, most of which are listed on the New York Stock Exchange.
The S&P 500 Index assigns relative values to the stocks included in the index,
weighted accordingly to each stock's total market value relative to the total
market value of the other stocks included in the index. The table, like the bar
chart, provides some indication of the risks of investing in the Fund by showing
how the Fund's average annual total returns for 1 year and since inception
compare with those of a broad measure of market performance. Past performance is
not necessarily an indicator of how the Fund will perform in the future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------- ------------------
Investor Class (.77)% 13.14%*
S&P 500 Index 28.57% 28.55%

*Commenced operations on January 16, 1997.

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Investor Class of the Fund.
The table is based on expenses for the Investor Class of the Fund for the most
recent fiscal year ended August 31, 1999.

INVESTOR CLASS
--------------
ANNUAL FUND OPERATING EXPENSES
(expenses that are deducted from Fund assets)

Management fees ...................................... 0.75%
Distribution (12b-1) fees ............................ 0.25%
Other expenses(1) .................................... 0.52%
----
Total annual Fund operating expenses ............. 1.52%
Fee waivers(2) ....................................... 0.30%
----
Net expenses ......................................... 1.22%
====

(1) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Investor Class.

(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.22%.

<PAGE>

EXAMPLE

The example is intended to help you compare the cost of investing in the
Investor Class of the Fund with the cost of investing in other mutual funds. The
example assumes that you invest $10,000 in the Investor Class of the Fund for
the time periods indicated and then redeem all of your shares at the end of each
period. The example also assumes that your investment has a 5% return each year
and that the operating expenses of the Investor Class of the Fund remain the
same, except for the expiration of the fee waivers and reimbursements on
December 31, 2000. Although your actual costs may be higher or lower, based on
these assumptions your cost would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$124 $451 $801 $1,787

<PAGE>

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

<TABLE>
<CAPTION>
LARGE CAP VALUE FUND
----------------------------------------------
FOR THE FOR THE FOR THE PERIOD
YEAR ENDED YEAR ENDED JANUARY 16, 1997*
AUGUST 31, AUGUST 31, THROUGH AUGUST 31,
1999 1998 1997
---------- ---------- ------------------
INVESTOR INVESTOR INVESTOR
CLASS CLASS CLASS
---------- ---------- ------------------
<S> <C> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period .............................. $ 10.70 $ 12.45 $ 10.20
------- ------- -------
Net investment income/(loss) (1) .................................. 0.15 0.06 0.02
Net realized and unrealized gain/(loss) on investments (2) ........ 1.65 (1.27) 2.23
------- ------- -------
Net increase/(decrease) in net assets resulting from operations. .. 1.80 (1.21) 2.25
------- ------- -------
Dividends to shareholders from:
Net investment income ............................................. (0.03) (0.06) --
Net realized capital gains ........................................ (0.11) (0.48) --
------- ------- -------
Total dividends and distributions to shareholders ................. (0.14) (0.54) --
------- ------- -------
Net asset value, end of period .................................... $ 12.36 $ 10.70 $ 12.45
======= ======= =======
Total investment return (3) ....................................... 16.86% (10.28%) 22.06%
======= ======= =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) ...................... $ 1,637 $ 6,150 $ 683
Ratio of expenses to average net assets (1) .................... 1.25% 1.19% 1.11%(4)
Ratio of expenses to average net assets without
waivers and expense reimbursements ........................... 1.55% 1.74% 3.05%(4)
Ratio of net investment income to average net assets (1) ....... 0.36% 0.68% 0.91%(4)
Portfolio turnover rate ........................................ 156.16% 111.68% 67.16%
<FN>
- --------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS MID CAP VALUE FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

INVESTMENT GOALS

The Fund seeks to provide long-term growth of capital primarily through
investment in equity securities. Current income is a secondary goal.

PRIMARY INVESTMENT STRATEGIES

The Adviser examines various factors in determining the value
characteristics of such issuers including 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, and
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.

The Fund may also invest up to 20% of its total assets in non U.S.
dollar-denominated securities.

KEY RISKS

(BULLET) Investors may lose money.

(BULLET) The Fund may, for temporary defensive purposes, invest a
percentage of its total assets, without limitation, in cash or various
U.S. dollar-denominated money market instruments. The value of money
market instruments tends to fall when current interest rates rise. Money
market instuments are generally less sensitive to interest rate changes
than longer-term securities. When the Fund's assets are invested in these
instruments, the Fund may not be achieving its investment objective.

9
<PAGE>

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

PRIOR PERFORMANCE

ANNUAL TOTAL RETURNS AS OF DECEMBER 31

The bar chart below shows the total return for the Investor Class of the
Fund during its first full calendar year. Past performance is not necessarily an
indicator of how the Fund will perform in the future.

[GRAPHIC OMITTED]

EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

1998
-------
(2.20%)

Since inception (June 2, 1997), the highest calendar quarter total return
for the Investor Class of the Fund was 13.64% (quarter ended March 31, 1998) and
the lowest calendar quarter total return was (20.89)% (quarter ended September
30, 1998). The total return was (10.20)% for the nine months ended September 30,
1999.

<PAGE>

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Investor Class,
compare with the Russell 2500 Index for the same periods. The Russell 2500 Index
is an unmanaged index (with no defined investment objective) of common stocks,
includes reinvestment of dividends and is a registered trademark of the Frank
Russell Corporation. The table, like the bar chart, provides some indication of
the risks of investing in the Fund by showing how the Fund's average annual
total returns for 1 year and since inception compare with those of a broad
measure of market performance. Past performance is not necessarily an indicator
of how the Fund will perform in the future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------ ---------------
Investor Class (2.20)% 8.20%*
Russell 2500 Index 0.38% 10.32%

*Commenced operations on June 2, 1997.

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Investor Class of the Fund.
The table is based on expenses for the Investor Class of the Fund for the most
recent fiscal year ended August 31, 1999.

INVESTOR CLASS
--------------
ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ............................................. 0.80%
Distribution (12b-1) fees ................................... 0.25%
Other expenses(1) ........................................... 0.42%
----
Total annual Fund operating expenses .................... 1.47%
Fee waivers(2) .............................................. 0.25%
----
Net expenses ................................................ 1.22%
====

(1) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Investor Class.

(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.22%.

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$124 $440 $779 $1,736

<PAGE>

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

<TABLE>
<CAPTION>
MID CAP VALUE FUND
---------------------------------------------
FOR THE FOR THE FOR THE PERIOD
YEAR ENDED YEAR ENDED JUNE 2, 1997*
AUGUST 31, AUGUST 31, THROUGH AUGUST 31,
1999 1998 1997
---------- ---------- ------------------
INVESTOR INVESTOR INVESTOR
CLASS CLASS CLASS
---------- ---------- ------------------
<S> <C> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ................................ $ 9.42 $ 11.01 $ 10.00
------- ------- -------
Net investment income/(loss) (1) .................................... (0.01) 0.01 0.01
Net realized and unrealized gain/(loss) on investments (2) .......... 1.97 (1.38) 1.00
------- ------- -------
Net increase/(decrease) in net assets resulting from operations. .... 1.96 (1.37) 1.01
------- ------- -------
Dividends to shareholders from:
Net investment income ............................................... -- (0.01) --
Net realized capital gains .......................................... -- (0.21) --
------- ------- -------
Total dividends and distributions to shareholders ................... -- (0.22) --
------- ------- -------
Net asset value, end of period ...................................... $ 11.38 $ 9.42 $ 11.01
======= ======= =======
Total investment return (3) ......................................... 20.81% (12.77%) 10.10%
======= ======= =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) ........................ $ 2,762 $ 1,828 $ 598
Ratio of expenses to average net assets (1) ...................... 1.25% 1.15% 1.10%(4)
Ratio of expenses to average net assets without
waivers and expense reimbursements ............................. 1.50% 1.82% 12.62%(4)
Ratio of net investment income to average net assets (1) ......... 0.01% (0.02%) 0.61%(4)
Portfolio turnover rate .......................................... 200.09% 167.86% 21.80%
<FN>
- ------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

INVESTMENT GOALS

The Fund seeks long-term growth of capital primarily through investment in
equity securities. Current income is a secondary objective.

PRIMARY INVESTMENT STRATEGIES

The Adviser examines various factors in determining the value
characteristics of such issuers including 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 fundamental analysis of industries and companies, earnings power and growth
and other investment criteria.

The Fund may invest up to 25% of its total assets in equity securities of
foreign issuers, including American Depository Receipts ("ADRs") and European
Depository Receipts ("EDRs").

13
<PAGE>

KEY RISKS

(BULLET) Investors may lose money.

(BULLET) Although the Fund will invest in stocks the Adviser believes to be
undervalued, there is no guarantee that the prices of these stocks will
not move even lower.

<PAGE>

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Investor Class of the Fund.
The table is based upon expenses for the Investor Class of the Fund for the most
recent fiscal year ended August 31, 1999.

INVESTOR CLASS*
---------------
SHAREHOLDER FEES (fees paid directly from your investment)

Maximum sales charge imposed on purchases .................. None
Maximum deferred sales charge .............................. None
Maximum sales charge imposed on reinvested dividends ....... None
Redemption Fee(1) .......................................... 1.00%
Exchange Fee ............................................... None

ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ............................................ 1.25%
Distribution (12b-1) fees .................................. 0.25%
Other expenses(2) .......................................... 16.56%
-----
Total annual Fund operating expenses ................... 18.06%
Fee waivers and expense reimbursements(3) .................. 16.29%
-----
Net expenses ............................................... 1.77%
======

* The Fund was renamed the Small Cap Value Fund II on February 18, 2000.

(2) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Investor Class.

(3) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 1.77%.

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$180 $3,437 $5,900 $9,736

<PAGE>

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

<TABLE>
<CAPTION>
SMALL CAP VALUE FUND II (DAGGER)
-----------------------------------
FOR THE FOR THE PERIOD
YEAR ENDED JULY 1, 1998*
AUGUST 31, THROUGH AUGUST 31,
1999 1998
-------------- ------------------
INVESTOR CLASS INVESTOR CLASS
-------------- ------------------
<S> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ...................................... $ 7.63 $ 10.00
------ -------
Net investment income/(loss) (1) .......................................... (0.02) (0.01)
Net realized and unrealized gain/(loss) on investments (2) ................ 1.04 (2.36)
------ -------
Net increase/(decrease) in net assets resulting from operations. .......... 1.02 (2.37)
------ -------
Dividends to shareholders from:
Net investment income ..................................................... -- --
Net realized capital gains ................................................ -- --
------ -------
Total dividends and distributions to shareholders ......................... -- --
------ -------
Net asset value, end of period ............................................ $ 8.65 $ 7.63
====== =======
Total investment return (3) (5) ........................................... 13.37% (23.70%)
====== =======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) .............................. $ 293 $ 129
Ratio of expenses to average net assets (1) ............................ 1.80% 1.80%(4)
Ratio of expenses to average net assets without waivers and
expense reimbursements ............................................... 18.09% 18.61%(4)
Ratio of net investment income to average net assets (1) ............... (0.42%) (0.66%)(4)
Portfolio turnover rate ................................................ 87.48% 11.97%
<FN>
- -------------
(DAGGER) The Fund's name was changed from the Micro Cap Value Fund to the Small
Cap Value Fund II on February 18, 2000.
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
(5) Redemption fee of 1.00% is not reflected in total return calculations.
</FN>
</TABLE>

16
<PAGE>

BOSTON PARTNERS BOND FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS
TOTAL RETURN: A way of measuring Fund performance. Total return is based on a
calculation that takes into account income dividends, capital gain distributions
and the increase or decrease in share price.
FIXED-INCOME SECURITIES: Fixed-income securities are generally bonds, which are
a type of security that functions like a loan. Bonds are "IOUs" issued by
private companies, municipalities or government agencies. By comparison, when
you buy a stock, you are buying ownership in a company. With a bond, your "loan"
is for a specific period, usually 5 to 30 years. You receive regular interest
payments at a fixed rate. Hence the term "fixed-income" security.
INVESTMENT-GRADE FIXED-INCOME SECURITIES: Securities which are rated at the time
of purchase "AAA," "AA," "A," or "BBB" by S&P, "Aaa," "Aa," "A" or "Baa" by
Moody's or which are similarly rated by another Rating Organization or are
unrated but deemed by the Adviser to be comparable in quality to instruments
that are so rated. Debt securities rated "BBB" by S&P, "Baa" by Moody's or the
equivalent rating of another Rating Organization, while still deemed
investment-grade, are considered to have speculative characteristics and are
more sensitive to economic change than higher rated bonds.
CORPORATE DEBT OBLIGATIONS: A long-term bond issued by a corporation, including
railroads and public utilities.
MORTGAGE-BACKED SECURITIES: Pools of mortgage loans assembled for sale to
investors by various governmental agencies as well as by private issuers.
ASSET-BACKED SECURITIES: Pools of assets, usually loans such as installment sale
contracts or credit card receivables, assembled for sale by private issuers.
MATURITY: The date on which an investor in a fixed income security will be paid
in full by the issuer.
================================================================================

INVESTMENT GOALS

The Fund seeks to maximize total return by investing principally in
investment grade fixed-income securities. Current income is a secondary goal.

PRIMARY INVESTMENT STRATEGIES

KEY RISKS

(BULLET) The net asset value ("NAV") of the Fund will change with changes
in the market value of its portfolio positions.

(BULLET) Investors may lose money.

17
<PAGE>

portfolio turnover could result in taxable capital gains. The annual
portfolio turnover rate for the Fund is not expected to exceed 100%,
however, it may be higher if the Adviser believes it will improve the
Fund's performance.

PRIOR PERFORMANCE

ANNUAL TOTAL RETURNS AS OF DECEMBER 31

[GRAPHIC OMITTED]

EDGAR REPRESENTATION OF DATA POINTS USED IN PRINTED GRAPHIC

7.09%
-----
1998

Since inception (December 30, 1997), the highest calendar quarter total
return for the Investor Class of the Fund was 2.42% (quarter ended September 30,
1998) and the lowest calendar quarter total return was (.58)% (quarter ended
March 31, 1999). The total return was (.14)% for the nine months ended September
30, 1999.

<PAGE>

AVERAGE ANNUAL TOTAL RETURNS -- COMPARISON

The table below shows how the Fund's average annual total returns for the
past one calendar year and since inception, with respect to the Investor Class,
compare with the Lehman Brothers Aggregate Index for the same periods. The
Lehman Brothers Aggregate Index is an unmanaged index containing fixed-income
securities rated investment grade or higher by Moody's, S&P or Fitch Investors
Service. All issues have at least one year to maturity and an outstanding par
value of at least $100 million. The Lehman Brothers Aggregate Index is a
registered trademark of Lehman Brothers, Inc. The table, like the bar chart,
provides some indication of the risks of investing in the Fund by showing how
the Fund's average annual total returns for 1 year and since inception compare
with those of a broad measure of market performance. Past performance is not
necessarily an indicator of how the Fund will perform in the future.

AVERAGE ANNUAL TOTAL RETURNS AS OF DECEMBER 31
----------------------------------------------
1 YEAR SINCE INCEPTION
------ --------------
Investor Class 7.09% 7.16%*
Lehman Aggregate Index 8.69% 8.64%

*Commenced operations on December 30, 1997.

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Investor Class of the Fund.
The table is based upon expenses for the Investor Class of the Fund for the most
recent fiscal year ended August 31, 1999.

INVESTOR CLASS
--------------
ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ............................................ 0.40%
Distribution (12b-1) fees .................................. 0.25%
Other expenses(1) .......................................... 1.79%
----
Total annual Fund operating expenses ................... 2.44%
Fee waivers and expense reimbursements(2) .................. 1.62%
----
Net expenses ............................................... 0.82%
====
(1)"Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Investor Class.
(2) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed .82%.

EXAMPLE

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$84 $605 $1,154 $2,653

<PAGE>

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

<TABLE>
<CAPTION>
BOND FUND
-------------------------------------
FOR THE FOR THE PERIOD
YEAR ENDED DECEMBER 30, 1997*
AUGUST 31, THROUGH AUGUST 31,
1999 1998
---------- ------------------
INVESTOR INVESTOR
CLASS CLASS
---------- ------------------
<S> <C> <C>
Per Share Operating Performance**
Net asset value, beginning of period ...................................... $10.10 $10.00
------ ------
Net investment income/(loss) (1) .......................................... 0.93 0.62
Net realized and unrealized gain/(loss) on investments (2) ................ (0.90) (0.16)
------ ------
Net increase/(decrease) in net assets resulting from operations ........... 0.03 0.46
------ ------
Dividends to shareholders from:
Net investment income ..................................................... (0.55) (0.36)
Net realized capital gains ................................................ (0.11) --
------ ------
Total dividends and distributions to shareholders ......................... (0.66) (0.36)
------ ------
Net asset value, end of period ............................................ $ 9.47 $10.10
====== ======
Total investment return (3) ............................................... 0.17% 4.63%
====== ======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) .............................. $ 188 $ 198
Ratio of expenses to average net assets (1) ............................ 0.85% 0.85%(4)
Ratio of expenses to average net assets without waivers and
expense reimbursements ............................................... 2.47% 2.72%(4)
Ratio of net investment income to average net assets (1) ............... 5.97% 5.83%(4)
Portfolio turnover rate ................................................ 57.60% 45.27%
<FN>

- ---------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
</FN>
</TABLE>

<PAGE>

BOSTON PARTNERS MARKET NEUTRAL FUND
- --------------------------------------------------------------------------------

================================================================================
IMPORTANT DEFINITIONS

MARKET NEUTRAL: Refers to a strategy of investing or engaging in transactions in
equity securities, while seeking to minimize the impact of movements in the
equity markets.

SALOMON SMITH BARNEY U.S. 1-MONTH TREASURY BILL INDEX(TRADE MARK): An unmanaged
index containing monthly return equivalents of yield averages that are not
marked to market.

FEDERAL FUNDS RATE: The rate of interest charged by a Federal Reserve bank for
member banks to borrow their federally required reserve.

MARKET CAPITALIZATION: Market capitalization refers to the market value of a
company and is calculated by multiplying the number of shares outstanding by the
current price per share.

INVESTMENT GOALS

PRIMARY INVESTMENT STRATEGIES

<PAGE>

KEY RISKS

(BULLET) The net asset value ("NAV") of the Fund will change with changes
in the market value of its portfolio positions.

(BULLET) Investors may lose money.

(BULLET) Short sales of securities may result in gains if a security's
price declines, but may result in losses if a security's price does not
decline in price.

(BULLET) The Fund could lose money if a seller under a repurchase agreement
defaults or declares bankruptcy.

(BULLET) If the Fund frequently trades its portfolio securities, the Fund
will incur higher brokerage commissions and transaction costs, which
could lower the Fund's performance. In addition to lower performance,
high portfolio turnover could result in taxable capital gains. The annual
portfolio turnover rate for the Fund is not expected to exceed 200%,
however, it may be higher if the Adviser believes it will improve the
Fund's performance.

<PAGE>

EXPENSES AND FEES

Fund investors pay various expenses, either directly or indirectly. The
purpose of the following table and example is to describe the fees and expenses
that you may pay if you buy and hold shares of the Investor Class of the Fund.
The table is based on expenses for the Investor Class of the Fund for the period
November 17, 1998 (commencement of operations) through August 31, 1999.

INVESTOR CLASS
--------------

SHAREHOLDER FEES (fees paid directly from your investment)

Maximum sales charge imposed on purchases ................... None
Maximum deferred sales charge ............................... None
Maximum sales charge imposed on reinvested dividends ........ None
Redemption Fee(1) ........................................... 1.00%
Exchange Fee ................................................ None

ANNUAL FUND OPERATING EXPENSES (expenses that are deducted
from Fund assets)

Management fees ............................................. 2.25%
Distribution (12b-1) fees ................................... 0.25%
Other expenses(2) ........................................... 24.08%
-----
Total annual Fund operating expenses .................... 26.58%
Fee waivers and expense reimbursements(3) ................... 23.41%
-----
Net expenses ................................................ 3.17%
-----

(2) "Other expenses" include audit, administration, custody, legal,
registration, transfer agency and miscellaneous other charges for the
Investor Class. "Other expenses" and "Total annual Fund operating
expenses" include dividends on securities which the Fund has sold short
("short-sale dividends"). Short-sale dividends generally reduce the
market value of the securities by the amount of the dividend declared
-- thus increasing the Fund's unrealized gain or reducing the Fund's
unrealized loss on the securities sold short. Short-sale dividends are
treated as an expense, and increase the Fund's total expense ratio,
although no cash is received or paid by the Fund. The amount of
short-sale dividends is estimated at 0.45% of average net assets for
the current fiscal year.

(3) The Adviser has agreed that until December 31, 2000, it will waive
advisory fees and reimburse expenses to the extent that total annual
Fund operating expenses exceed 2.72% (excluding short sale dividend
expenses).

EXAMPLE
The example is intended to help you compare the cost of investing in the
Investor Class of the Fund with the cost of investing in other mutual funds. The
example assumes that you invest $10,000 in the Investor Class of the Fund for
the time periods indicated and then redeem all of your shares at the end of each
period. The example also assumes that your investment has a 5% return each year
and that the operating expenses of the Investor Class of the Fund remain the
same, except for the expiration of the fee waivers and reimbursements on
December 31, 2000. Although your actual costs may be higher or lower, based on
these assumptions your cost would be:

1 YEAR 3 YEARS 5 YEARS 10 YEARS
------ ------- ------- --------
$320 $4,628 $7,277 $10,254

<PAGE>

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

MARKET NEUTRAL FUND
-------------------
FOR THE PERIOD
NOVEMBER 17, 1998*
THROUGH AUGUST 31,
1999
-------------------
INVESTOR CLASS
-------------------
Per Share Operating Performance**
Net asset value, beginning of period $ 10.00
-------
Net investment income/(loss) (1) 0.06
Net realized and unrealized gain/(loss)
on investments (2) (0.63)
-------
Net increase/(decrease) in net assets
resulting from operations (0.57)
-------
Dividends to shareholders from:
Net investment income --
Net realized capital gains --
-------
Total dividends and distributions to shareholders --
-------
Net asset value, end of period $ 9.43
=======
Total investment return (3) (5) (5.70%)
=======
Ratios/Supplemental Data
Net assets, end of period (000's omitted) $ 231
Ratio of expenses to average net assets (1) 2.75%(4)(6)
Ratio of expenses to average net assets
without waivers and expense reimbursements 26.61%(4)(6)
Ratio of net investment income
to average net assets (1) 1.32%(4)
Portfolio turnover rate 218.41%

- -------------
* Commencement of operations.
** Calculated based on shares outstanding on the first and last day of the
respective periods, except for dividends and distributions, if any, which
are based on actual shares outstanding on the dates of distributions.
(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 not annualized.
(4) Annualized.
(5) Redemption fee of 1.00% is not reflected in total return calculations.
(6) Without the voluntary waiver of advisory and administration fees, the ratios
of expenses to average net assets for the Investor Class would have been
26.61% (excluding dividend expense) and 27.02% (including dividend expense)
annualized for the period ended August 31, 1999.

<PAGE>

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

INVESTMENT ADVISOR

Boston Partners Asset Management, L.P. (the "Adviser"), located at 28 State
Street, 21st Floor, Boston, Massachusetts 02109, provides investment advisory
services to the Funds. The Adviser provides investment management and investment
advisory services to investment companies and other institutional accounts. As
of October 31, 1999, the Adviser managed approximately $10.2 billion in assets.
The Adviser is organized as a Delaware limited partnership whose sole general
partner is Boston Partners, Inc., a Delaware corporation. The Adviser manages
each Fund's business and investment activities subject to the authority of the
Company's Board of Directors.

PORTFOLIO MANAGERS

BOSTON PARTNERS LARGE CAP VALUE FUND

BOSTON PARTNERS MID CAP VALUE FUND

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 $1.5 billion in mid-capitalization activities as
well as $1 billion in small capitalization activities. Prior to joining the
Adviser in April 1995, Mr. Archambo was employed by The Boston Company Asset
Management, Inc. from 1989 through April 1995 where he was a senior portfolio
manager. Mr. Archambo has over 15 years of investment experience and is a CFA.
For the fiscal year ended August 31, 1999, the Fund paid .70% (expressed as a
percentage of average net assets) to the Adviser for its services.

BOSTON PARTNERS SMALL CAP VALUE FUND II

<PAGE>

BOSTON PARTNERS BOND FUND

BOSTON PARTNERS MARKET NEUTRAL FUND

OTHER SERVICE PROVIDERS

The following chart shows the Funds' other service providers and includes
their addresses and principal activities.

<PAGE>

------------
SHAREHOLDERS
------------

Distribution and
Shareholder Services

------------------------------------ -----------------------------------------
PRINCIPAL DISTRIBUTOR TRANSFER AGENT

PROVIDENT DISTRIBUTORS, INC. PFPC INC.
3200 HORIZON DRIVE 400 BELLEVUE PARKWAY
KING OF PRUSSIA, PA 19406 WILMINGTON, DE 19809

Distributes shares of the Handles shareholder services,
BOSTON PARTNERS Fund. including recordkeeping and statements,
distribution of dividends and processing
of buy, sell and exchange requests.
------------------------------------ -----------------------------------------

Asset
Management

------------------------------------ -----------------------------------------
INVESTMENT ADVISER CUSTODIAN

BOSTON PARTNER ASSET PFPC TRUST COMPANY
MANAGEMENT, L.P. 200 STEVENS DRIVE
28 STATE STREET 21ST FLOOR LESTER, PA 19113
BOSTON, MA 02109

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

Fund
Operations

------------------------------------
ADMINISTRATOR

PFPC INC.
400 BELLEVUE PARKWAY
WILMINGTON, DE 19809

Provides facilities, equipment
and personnel to carry out
administrative services related
to each Fund and calculates the
Fund's NAV, dividends
and distributions.
------------------------------------

---------------------------------
BOARD OF DIRECTORS

Supervises the Fund's activities.
---------------------------------

<PAGE>

SHAREHOLDER INFORMATION
- --------------------------------------------------------------------------------

PRICING OF FUND SHARES

Investor Shares of the Funds ("Shares") are priced at their net asset value
("NAV"). The NAV for the Investor Class of each Fund is calculated by adding the
value of all securities, cash and other assets in a Fund's portfolio, deducting
the Fund's actual and accrued liabilities and dividing by the total number of
Shares outstanding.

PURCHASE OF FUND SHARES

Shares representing interests in the Funds are offered continuously for
sale by Provident Distributors, Inc. (the "Distributor"). The Board of Directors
of the Company has approved and adopted a Distribution Agreement and Plan of
Distribution for the Shares (the "Plan") pursuant to Rule 12b-1 under the
Investment Company Act of 1940. Under the Plan, the Distributor is entitled to
receive from the Funds 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 the Company's Board of Directors and by the
Distributor. Because these fees are paid out of the Funds' assets on an ongoing
basis, over time these fees will increase the cost of your investment and may
cost you more than paying other types of sales charges.

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 Funds' 12b-1
Plan. The Distributor may delegate some or all of these functions to Service
Organizations. See "Purchases Through Intermediaries" below.

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 Funds 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 Company. Therefore, you should contact the Service
Organization acting on your 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 your accounts with the Service
Organization. Service Organizations will be responsible for promptly
transmitting client or customer purchase and redemption orders to the Company in
accordance with their agreements with the Company and with clients or customers.
Service Organizations or, if applicable, their designees that have entered into
agreements with the

<PAGE>

Company or its agent may enter confirmed purchase orders on behalf of clients
and customers, with payment to follow no later than the Company'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 Company 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 Company in good order
will be priced at the appropriate 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, 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 net asset value of accounts with the Company 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 service provided, the operations processing requirements
of the relationship and the standardized fee schedule of the Service
Organization or recordkeeper.

GENERAL. You may also purchase Shares of each Fund at the NAV per share
next calculated after your order is received by PFPC Inc. (the "Transfer Agent")
in proper form as described below. After an initial purchase is made, the
Transfer Agent will set up an account for you on RBB's records. The minimum
initial investment in any Fund is $2,500 and the minimum additional investment
is $100. For purposes of meeting the minimum initial purchase, purchases by
clients which are part of endowments, foundations or other related groups may be
combined. You can only purchase Shares of each Fund on days the NYSE is open and
through the means described below.

INITIAL INVESTMENT BY MAIL. An account may be opened by completing and
signing the application included with this Prospectus and mailing it to the
Transfer Agent at the address noted below, together with a check ($2,500
minimum) payable to the Fund in which you would like to invest. Third party
checks will not be accepted.

BOSTON PARTNERS [NAME OF FUND]
c/o PFPC Inc.
P.O. Box 8852
Wilmington, DE 19899-8852

PNC Bank, NA
Philadelphia, Pennsylvania 19103
ABA# 0310-0005-3
Account # 86-1108-2507
F/B/O BOSTON PARTNERS [NAME OF FUND]
Ref. (Account Number)
Shareholder Name

Federal funds purchases will be accepted only on a day on which the NYSE
and PNC Bank, NA are open for business.

<PAGE>

ADDITIONAL INVESTMENTS. Additional investments may be made at any time
(minimum investment $100) by purchasing Shares of any Fund at NAV by mailing a
check to the Transfer Agent at the address noted above under "Initial Investment
by Mail" (payable to Boston Partners [name of Fund]) or by wiring monies to PNC
Bank, NA as outlined above under "Initial Investment by Wire." For each Fund,
notification must be given to the Transfer Agent at (888) 261-4073 prior to 4:00
p.m., Eastern time, on the wire date. Initial and additional purchases made by
check cannot be redeemed until payment of the purchase has been collected.

AUTOMATIC INVESTMENT PLAN. Additional investments in Shares of the Funds
may be made automatically by authorizing the Transfer Agent to withdraw funds
from your bank account through an Automatic Investment Plan ($100 minimum).
Investors desiring to participate in an Automatic Investment Plan should call
the Transfer Agent 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 PFPC Trust Company acts as
custodian. For further information as to applications and annual fees, contact
the Transfer Agent at (888) 261-4073. To determine whether the benefits of an
IRA are available and/or appropriate, you should consult with a tax adviser.

REDEMPTION OF FUND SHARES

REDEMPTION BY MAIL. Your redemption requests should be addressed to BOSTON
PARTNERS [name of Fund], c/o PFPC Inc., P.O. Box 8852, Wilmington, DE 19899-8852
and must include:

a. a letter of instruction specifying the number of shares or dollar
amount to be redeemed, signed by all registered owners of the shares in
the exact names in which they are registered;

c. other supporting legal documents, if required, in the case of estates,
trusts, guardianships, custodianships, corporations, pension and profit
sharing plans and other organizations.

<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 the Transfer Agent 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. The
systematic withdrawal 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 systematic 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 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 ten Business Days prior to the end
of the month preceding a scheduled payment.

TRANSACTION FEE ON CERTAIN REDEMPTIONS OF THE BOSTON PARTNERS SMALL CAP
VALUE FUND II AND BOSTON PARTNERS MARKET NEUTRAL FUND

<PAGE>

Fund sells certain securities in order to raise cash to meet the redemption
request; (3) the realization of capital gains by the other shareholders in each
Fund; and (4) the effect of the "bid-ask" spread in the over-the-counter market.
The 1.00% amount represents each Fund's estimate of the brokerage and other
transaction costs which may be incurred by each Fund in disposing of stocks in
which each Fund may invest. Without the additional transaction fee, each Fund
would generally be selling its shares at a price less than the cost to each Fund
of acquiring the portfolio securities necessary to maintain its investment
characteristics, resulting in reduced investment performance for all
shareholders in the Funds. With the additional transaction fee, the transaction
costs of selling additional stocks are not borne by all existing shareholders,
but the source of funds for these costs is the transaction fee paid by those
investors making redemptions of the Boston Partners Small Cap Value Fund II and
Boston Partners Market Neutral Fund.

OTHER REDEMPTION INFORMATION. Redemption proceeds for Shares of the Funds
recently purchased by check may not be distributed until payment for the
purchase has been collected, which may take up to fifteen days from the purchase
date.
Shareholders can avoid this delay by utilizing the wire purchase option.

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 Investor Shares of any Boston Partners Fund for Investor Shares of
another Boston Partners Fund, up to six (6) times per year. Such exchange will
be effected at the net asset value of the exchanged Investor Shares and the net
asset value of the Investor Shares to be acquired next determined after PFPC's
receipt of a request for an exchange. An exchange of Boston Partners Small Cap
Value Fund II or Boston Partners Market Neutral Fund Shares held for less than 1
year (with the exception of Shares purchased through dividend reinvestment or
the reinvestment of capital gains) will be subject to the 1.00% transaction fee.
An exchange of Shares will be treated as a sale for federal income tax purposes.
A shareholder may make an exchange by sending a written request to the Transfer
Agent or, if authorized, by telephone (see "Redemption by Telephone" above).

If the exchanging shareholder does not currently own Investor Shares of the
Fund whose Shares are being acquired, 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. See "Redemption By Mail" for information on
signature guarantees. The exchange privilege may be modified or terminated at
any time, or from time to time, by the Company, upon 60 days' written notice to
shareholders.

<PAGE>

DIVIDENDS AND DISTRIBUTIONS

TAXES

Any loss realized on Shares held for six months or less will be treated as
a long-term capital loss to the extent of any capital gain dividends that were
received on the Shares.

The one major exception to these tax principles is that distributions on,
and sales, exchanges and redemptions of, Shares held in an IRA (or other
tax-qualified plan) will not be currently taxable.

<PAGE>

MULTI-CLASS STRUCTURE

Each Fund also offers Institutional Shares, which are offered directly to
institutional investors in a separate prospectus. Shares of each class of the
Funds represent equal pro rata interests and accrue dividends and calculate net
asset value and performance quotations in the same manner. The performance of
each class is quoted separately due to different actual expenses. The total
return on Investor Shares of a Fund can be expected to differ from the total
return on Institutional Shares of the same Fund. Information concerning
Institutional class shares of the Funds can be requested by calling the Fund at
(888) 261-4073.

<PAGE>

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

CUSTODIAN
PFPC Trust Company
Lester, Pennsylvania

TRANSFER AGENT AND ADMINISTRATOR
PFPC Inc.
Wilmington, Delaware

DISTRIBUTOR
Provident Distributors,Inc.
King of Prussia, Pennsylvania

COUNSEL
Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

INDEPENDENT ACCOUNTANTS
PricewaterhouseCoopers LLP
Philadelphia, Pennsylvania

35
<PAGE>

BOSTON PARTNERS FAMILY OF FUNDS
OF
THE RBB FUND, INC.
(888) 261-4073
HTTP://WWW.BOSTONPARTNERSFUNDS.COM

FOR MORE INFORMATION:

ANNUAL/SEMI-ANNUAL REPORT

STATEMENT OF ADDITIONAL INFORMATION (SAI)

A Statement of Additional Information, dated December 1, 1999 (SAI), has
been filed with the Securities and Exchange Commission (SEC). The SAI, which
includes additional information about the BOSTON PARTNERS FAMILY OF FUNDS, may
be obtained free of charge, along with the annual and semi-annual reports, by
calling (888) 261-4073. The SAI, as supplemented from time to time, is
incorporated by reference into this Prospectus.

SHAREHOLDER INQUIRIES

PURCHASES AND REDEMPTIONS

Call (888) 261-4073.

WRITTEN CORRESPONDENCE

Post Office Address: BOSTON PARTNERS FAMILY OF FUNDS, c/o PFPC, Inc. PO Box
8852, Wilmington, DE 19899-8852

Street Address: BOSTON PARTNERS FAMILY OF FUNDS, c/o PFPC, Inc. 400
Bellevue Parkway, Wilmington, DE 19809

SECURITIES AND EXCHANGE COMMISSION (SEC)

INVESTMENT COMPANY ACT FILE NO. 811-05518