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Filed Pursuant to Rule 497(e)
Registration File No.: 33-54047
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER
SELECT DIMENSIONS INVESTMENT SERIES
Dated August 9, 1999
The sentences pertaining to the Global Equity Portfolio and the Emerging
Markets Portfolio of the Fund in the section of the prospectus entitled
"Portfolio Management" are hereby replaced by the following:
Global Equity Portfolio -- Mark Bavoso, a Senior Vice President of
the Investment Manager, is the primary portfolio manager of the
Portfolio and co-management is provided by David Dineen, a Vice
President of the Investment Manager and a member of the Growth
Group. Both Mr. Bavoso and Mr. Dineen have been portfolio
managers with the Investment Manager for over five years.
Emerging Markets Portfolio -- Saker Nusseibeh, Managing Director
of European and International Equities of TCW London International,
Limited and Michael P. Reilly, Managing Director of TCW Fund
Management Inc. are the primary portfolio managers of the Portfolio.
Mr. Nusseibeh has been a primary portfolio manager since October 1999;
prior to this, since 1996, he has served in various portfolio
management positions with TCW London International, Limited and
prior to 1996, he served as Director of the international division
of Mercury Asset Management. Mr. Reilly has been a primary portfolio
manager since December 1994 and has been a portfolio manager with
affiliates of TCW Group for over five years.
October 20, 1999
