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Filed Pursuant to Rule 497(e)
Registration File No.: 2-82510
SUPPLEMENT TO THE STATEMENT OF ADDITIONAL INFORMATION
OF
MORGAN STANLEY DEAN WITTER VARIABLE INVESTMENT SERIES
DATED MAY 1, 2000
The first sentence of the thirteenth paragraph of Section VIII. B. of the
Fund's Statement of Additional Information is hereby replaced by the following:
In the calculation of a Portfolio's net asset value (other than for the
Money Market Portfolio): (1) an equity portfolio security listed or
traded on the New York or American Stock Exchange, NASDAQ, or other
exchange is valued at its latest sale price, prior to the time when
assets are valued; if there were no sales that day, the security is
valued at the latest bid price (in cases where a security is traded on
more than one exchange, the security is valued on the exchange designated
as the primary market pursuant to procedures adopted by the Trustees);
and (2) all other portfolio securities for which over-the-counter market
quotations are readily available are valued at the latest bid price.
July 31, 2000
