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SUPPLEMENT TO THE PROSPECTUS OF
DEAN WITTER SELECT DIMENSIONS INVESTMENT SERIES
DATED FEBRUARY 28, 1995
On October 26, 1995, the Trustees of Dean Witter Select Dimensions
Investment Series amended the investment policies of the Utilities Portfolio of
the Fund to increase the percentage of the Portfolio's total assets which may be
invested in foreign securities. Accordingly, the fifth sentence in the
subsection entitled "General Portfolio Techniques -- Foreign Securities" in the
section of the Prospectus entitled "Investment Objectives and Policies,"
appearing on page 32 of the Prospectus, is hereby replaced by the following:
The AMERICAN VALUE PORTFOLIO may invest up to 35% of the
value of its total assets, at the time of purchase, in foreign
securities. The UTILITIES PORTFOLIO may invest up to 20% of the
value of its total assets, at the time of purchase, in foreign
securities, with a maximum of 10% of the value of its total
assets, at the time of purchase, invested in such securities
that are not American Depository Receipts.
October 26, 1995
