<PAGE>
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 MAY 1, 2000
The information contained in the Prospectus with respect to the
Diversified Income Portfolio under the section entitled "Principal Investment
Strategies" is hereby amended as follows:
The second paragraph and the first clause of the third paragraph are
hereby replaced by the following:
The three groups of Portfolio investments include: (1) global securities;
(2) mortgage-backed and U.S. Government securities; and (3) high yield
securities.
(1) GLOBAL SECURITIES. The securities in the first group include:
Fixed-income securities issued or guaranteed by the U.S.
Government, its agencies or instrumentalities or fixed-income
securities issued or guaranteed by a foreign government or
supranational organization or any of their instrumentalities or
fixed-income securities issued by a corporation, all of which are
rated BBB or above by Standard & Poor's ("S&P") or Baa or above by
Moody's Investors Services ("Moody's") or, if unrated, are
determined by the Investment Manager to be of comparable quality;
The paragraph relating to the short-term remaining maturity of the
investments of the first group is hereby deleted.
October 26, 2000
