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SUPPLEMENT TO THE PROSPECTUS OF
DEAN WITTER SELECT DIMENSIONS INVESTMENT SERIES
DATED MAY 1, 1996
The sentences pertaining to the Emerging Markets Portfolio in the subsection
entitled "Portfolio Management" under the subsection entitled "General Portfolio
Techniques" in the section of the Prospectus entitled "INVESTMENT OBJECTIVES AND
POLICIES" are hereby replaced by the following:
Shaun C.K. Chan, Managing Director of TCW Asia Ltd.,
Terence F. Mahony, a Managing Director of the Sub-Adviser,
and Michael P. Reilly, Senior Vice President of the
Sub-Adviser, are the primary portfolio managers of the
EMERGING MARKETS PORTFOLIO. Mr. Chan has been a primary
portfolio manager of the Portfolio since the Fund's
inception and has been a portfolio manager with affiliates
of The TCW Group, Inc. since 1993, prior to which time he
was Director of Wardley Investment Services (Hong Kong)
Ltd. Mr. Mahony has been a primary portfolio manager of
the Portfolio since July, 1996 and has been a portfolio
manager with the Sub-Adviser since April, 1996, prior to
which time he was Chief Investment Officer for Global
Emerging Markets at HSBC Asset Management (September,
1993-April 1996) and prior thereto was a Director at
Baring Asset Management. Mr. Reilly has been a primary
portfolio manager of the Portfolio since December, 1994
and has been a portfolio manager with affiliates of The
TCW Group, Inc. since June, 1992, prior to which time he
was Vice President of Security Pacific Bank.
July 31, 1996
