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Filed Pursuant to Rule 497(e)
Registration File No.: 2-82510
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER VARIABLE INVESTMENT SERIES
DATED AUGUST 5, 1999
The Aggressive Equity Portfolio of the Fund has eliminated its policy of
normally investing at least 65% of its assets in equity securities of companies
covered by Morgan Stanley Dean Witter Equity Research ("MSDW Equity Research").
Accordingly, the first sentence of the section entitled "Principal Investment
Strategies" on page 39 of the Prospectus is hereby replaced by the following:
The Portfolio will normally invest at least 65% of its assets in
equity securities of companies that the "Investment Manager," Morgan
Stanley Dean Witter Advisors, Inc., believes offer the potential for
superior earnings growth.
Other references on page 39 of the Prospectus to MSDW Equity Research, and
its analysis, research and/or coverage of equities, and to investments by the
Aggressive Equity Portfolio in companies covered by MSDW Equity Research are
hereby deleted.
March 15, 2000
