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SUPPLEMENT TO THE PROSPECTUS OF
DEAN WITTER SELECT DIMENSIONS INVESTMENT SERIES
DATED MAY 1, 1997
The eleventh paragraph under the heading "The Fund and its Management"
appearing on page 12 of the Prospectus is hereby amended to read as follows:
The MID-CAP GROWTH PORTFOLIO commenced operations on January
21, 1997. The Investment Manager has undertaken to assume all
expenses of the MID-CAP GROWTH PORTFOLIO (except for any
brokerage fees) and waive the compensation provided for that
Portfolio in its Management Agreement with the Fund until such
time as the Portfolio has $50 million of net assets or until
July 31, 1998, whichever occurs first.
July 21, 1997
