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SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER SELECT DIMENSIONS
INVESTMENT SERIES
DATED MARCH 2, 1998, REVISED MAY 1, 1998
The twelfth paragraph under the heading "The Fund and its Management" appearing
on page 13 of the Prospectus is hereby amended 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 to
waive the compensation provided for the Portfolio in its Management
Agreement with the Fund until such time as the Portfolio has $50
million of net assets or until April 30, 1999, whichever occurs
first.
December 21, 1998
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