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MFS(R)/SUN LIFE SERIES TRUST
MANAGED SECTORS SERIES
SUPPLEMENT TO THE STATEMENT OF ADDITIONAL INFORMATION ("SAI")
The line item under the "Investment Policy" and "Percentage Limitation" table in
the "Investment Techniques, Practices and Risks" section for MFS Managed Sectors
Series on page 4 of the SAI is hereby restated as follows:
13. Managed Sectors Series
Foreign Securities..................................... up to 50%
The date of this Supplement is December 10, 1999.
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MFS(R)/SUN LIFE SERIES TRUST
EMERGING GROWTH SERIES
SUPPLEMENT TO THE CURRENT PROSPECTUS
The Emerging Growth Series may invest up to 25% of its net assets in foreign
securities, including emerging market securities. The section of the prospectus
entitled "Principal Risks of an Investment" is amended to add the following:
Foreign Markets Risk - Investing in foreign securities involves risks relating
to political social and economic developments abroad, as well as risks resulting
from the differences between the regulations to which U.S. and foreign issuers
and markets are subject:
o These risks may include the seizure by the government of company
assets, excessive taxation, withholding taxes on dividends and
interest, limitations on the use or transfer of portfolio assets, and
political or social instability.
o Enforcing legal rights may be difficult, costly and slow in foreign
countries, and there may be special problems enforcing claims against
foreign governments.
o Foreign companies may not be subject to accounting standards or
governmental supervision comparable to U.S. companies, and there may
be less public information about their operations.
o Foreign markets may be less liquid and more volatile than U.S.
markets.
o Foreign securities often trade in currencies other than the U.S.
dollar, and the fund may directly hold foreign currencies and purchase
and sell foreign currencies through forward exchange contracts.
Changes in currency exchange rates will affect the fund's net asset
value, the value of dividends and interest earned, and gains and
losses realized on the sale of securities. An increase in the strength
of the U.S. dollar relative to these other currencies may cause the
value of the fund to decline. Certain foreign currencies may be
particularly volatile, and foreign governments may intervene in the
currency markets, causing a decline in value or liquidity in the
fund's foreign currency holdings. By entering into forward foreign
currency exchange contracts, the fund may be required to forego the
benefits of advantageous changes in exchange rates and, in the case of
forward contracts entered into for the purpose of increasing return,
the fund may sustain losses which will reduce its gross income.
Forward foreign currency exchange contracts involve the risk that the
party with which the fund enters the contract may fail to perform its
obligations to the fund.
Emerging Markets Risk - Emerging markets are generally defined as countries in
the initial stages of their industrialization cycles with low per capita income.
Investments in emerging markets securities involve all of the risks of
investments in foreign securities, and also have additional risks:
o All of the risks of investing in foreign securities are heightened by
investing in emerging markets countries.
o The markets of emerging markets countries have been more volatile than
the markets of developed countries with more mature economies. These
markets often have provided significantly higher or lower rates of
return than developed markets, and significantly greater risks, to
investors.
The date of this Supplement is December 10, 1999.
