<PAGE>
SCHRODER SERIES TRUST
PROSPECTUS SUPPLEMENT
To Investor Shares Prospectus dated March 1, 1999
SCHRODER INVESTMENT GRADE INCOME FUND
Schroder believes that it is appropriate to change the comparative performance
index for the Schroder Investment Grade Income Fund (the "Fund") from the Lehman
Brothers Government/Corporate Index to the Lehman Brothers Aggregate Bond Index
(the "Aggregate Index") because the Aggregate Index is more representative of
the Fund's permissible investment universe.
The table entitled Average Annual Total Returns for Schroder Investment Grade
Income Fund on page 9 of the Prospectus and the accompanying footnote are
deleted and replaced with the following:
<TABLE>
<CAPTION>
- --------------------------------------------------------------------------------------------------
AVERAGE ANNUAL TOTAL RETURNS LIFE OF FUND
(FOR PERIODS ENDED DECEMBER 31, 1998) PAST ONE YEAR (SINCE 2/22/94)
- --------------------------------------------------------------------------------------------------
<S> <C> <C>
Schroder Investment Grade Income Fund 7.79% 6.33%
- --------------------------------------------------------------------------------------------------
Lehman Brothers Aggregate Bond Index* 8.69% 7.51%
- --------------------------------------------------------------------------------------------------
</TABLE>
* The Lehman Brothers Aggregate Bond Index (the "Aggregate Index") is a
composite index which measures the total universe of investment grade fixed
income securities in the U.S., including government, corporate, mortgage-backed,
asset-backed, and international dollar-denominated bonds, all with maturities
greater than one year. The Aggregate Index has replaced the Lehman Brothers
Government/Corporate Index (a composite of approximately 5,000 investment grade
government and corporate debt issues with maturities greater than one year) as
the Fund's comparative index in this Prospectus because Schroder believes the
Aggregate Index is more representative of the Fund's permissible investment
universe. For periods ended December 31, 1998, the Past One Year and Life of
Fund (since 2/22/94) average annual total returns of the Lehman Brothers
Government/Corporate Index were 9.47% and 7.57%, respectively.
SCHRODER MIDCAP VALUE FUND
Schroder MidCap Value Fund invests primarily in securities of mid-cap companies,
which are described in the Prospectus as companies with market capitalizations
of between $750 million and $5 billion. The Trustees have approved an increase
in those market capitalizations, based on Schroder's view that the market
capitalizations of companies considered generally to be "mid-cap" companies have
increased and that the change would bring the Fund more closely in line with
comparable mutual funds and securities indices against which the Fund's
performance is compared. Accordingly, the
<PAGE>
paragraph describing Schroder MidCap Value Fund on page 1 of the Prospectus is
replaced with the following:
SCHRODER MIDCAP VALUE FUND seeks long-term capital appreciation. The Fund
invests primarily in equity securities of mid-cap companies (companies
with market capitalizations of between $1 billion and $10 billion).
The first sentence of the second paragraph on page 7 of the Prospectus is
replaced with the following:
The Fund normally invests at least 65% of its assets in equity securities
of mid-cap companies - companies with market capitalizations of between $1
billion and $10 billion.
INVESTMENT ADVISER
On July 1, 1999, Schroder was reorganized into a newly created Delaware
corporation, Schroder Investment Management North America Inc. ("SIMNA"). SIMNA
now serves as the investment adviser to each of the Funds. The reorganization
did not result in any change in fees paid by the Funds or in the services
provided to the Funds or in the personnel providing those services.
October 25, 1999
<PAGE>
SCHRODER SERIES TRUST
PROSPECTUS SUPPLEMENT
To Advisor Shares Prospectus dated March 1, 1999
SCHRODER INVESTMENT GRADE INCOME FUND
Schroder believes that it is appropriate to change the comparative performance
index for the Schroder Investment Grade Income Fund (the "Fund") from the Lehman
Brothers Government/Corporate Index to the Lehman Brothers Aggregate Bond Index
(the "Aggregate Index") because the Aggregate Index is more representative of
the Fund's permissible investment universe.
The table entitled Average Annual Total Returns for Schroder Investment Grade
Income Fund on page 9 of the Prospectus and the accompanying footnote are
deleted and replaced with the following:
<TABLE>
<CAPTION>
- --------------------------------------------------------------------------------------------------
AVERAGE ANNUAL TOTAL RETURNS LIFE OF FUND
(FOR PERIODS ENDED DECEMBER 31, 1998) PAST ONE YEAR (SINCE 2/22/94)
- --------------------------------------------------------------------------------------------------
<S> <C> <C>
Schroder Investment Grade Income Fund* 7.79% 6.33%
- --------------------------------------------------------------------------------------------------
Lehman Brothers Aggregate Bond Index** 8.69% 7.51%
- --------------------------------------------------------------------------------------------------
</TABLE>
* The bar chart and table show performance of the Fund's Investor Shares, which
are offered in a different prospectus. Although Advisor Shares and Investor
Shares would have similar annual returns (because all of the Fund's shares
represent interests in the same portfolio of securities), Advisor Share
performance would be lower than Investor Share performance because of the higher
expenses paid by Advisor Shares.
** The Lehman Brothers Aggregate Bond Index (the "Aggregate Index") is a
composite index which measures the total universe of investment grade fixed
income securities in the U.S., including government, corporate, mortgage-backed,
asset-backed, and international dollar-denominated bonds, all with maturities
greater than one year. The Aggregate Index has replaced the Lehman Brothers
Government/Corporate Index (a composite of approximately 5,000 investment grade
government and corporate debt issues with maturities greater than one year) as
the Fund's comparative index in this Prospectus because Schroder believes the
Aggregate Index is more representative of the Fund's permissible investment
universe. For periods ended December 31, 1998, the Past One Year and Life of
Fund (since 2/22/94) average annual total returns of the Lehman Brothers
Government/Corporate Index were 9.47% and 7.57%, respectively.
SCHRODER MIDCAP VALUE FUND
Schroder MidCap Value Fund invests primarily in securities of mid-cap companies,
which are described in the Prospectus as companies with market capitalizations
of between $750 million and $5 billion. The Trustees have approved an increase
in those market capitalizations, based on Schroder's view that the market
capitalizations of
<PAGE>
companies considered generally to be "mid-cap" companies have increased and that
the change would bring the Fund more closely in line with comparable mutual
funds and securities indices against which the Fund's performance is compared.
Accordingly, the paragraph describing Schroder MidCap Value Fund on page 1 of
the Prospectus is replaced with the following:
SCHRODER MIDCAP VALUE FUND seeks long-term capital appreciation. The Fund
invests primarily in equity securities of mid-cap companies (companies
with market capitalizations of between $1 billion and $10 billion).
The first sentence of the second paragraph on page 7 of the Prospectus is
replaced with the following:
The Fund normally invests at least 65% of its assets in equity securities
of mid-cap companies - companies with market capitalizations of between $1
billion and $10 billion.
INVESTMENT ADVISER
On July 1, 1999, Schroder was reorganized into a newly created Delaware
corporation, Schroder Investment Management North America Inc. ("SIMNA"). SIMNA
now serves as the investment adviser to each of the Funds. The reorganization
did not result in any change in fees paid by the Funds or in the services
provided to the Funds or in the personnel providing those services.
October 25, 1999
