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Filed Pursuant to Rule 497
Registration File No.: 33-54047
SUPPLEMENT TO PROSPECTUS OF
MORGAN STANLEY DEAN WITTER SELECT DIMENSIONS INVESTMENT SERIES
DATED MARCH 2, 1998, REVISED MAY 1, 1998
On April 22, 1999, the Board of Trustees of the Fund approved the
following changes respecting the Portfolios listed below:
(1) AMERICAN VALUE PORTFOLIO AND DIVIDEND GROWTH PORTFOLIO
With respect to each of these Portfolios, effective May 1, 1999, the Board
has amended the Fund's Investment Management Agreement to reduce the
Portfolio's investment management fee rates to be paid to Morgan Stanley Dean
Witter Advisors Inc. (the "Investment Manager") for assets exceeding specified
levels, so that the fees payable under the Agreement will be calculated daily
by applying the following annual rates to each of these Portfolios' net assets,
determined as of the close of each business day:
o AMERICAN VALUE PORTFOLIO -- 0.625% of the portion of daily net assets not
exceeding $500 million; and 0.60% of the portion of daily net assets
exceeding $500 million.
o DIVIDEND GROWTH PORTFOLIO -- 0.625% of the portion of daily net assets not
exceeding $500 million; 0.50% of the portion of daily net assets exceeding
$500 million but not exceeding $1 billion; and 0.475% of the portion of
daily net assets exceeding $1 billion.
(2) MID-CAP GROWTH PORTFOLIO
(a) Retention of Sub-Advisor -- The Board unanimously recommended that a
sub-advisory agreement between the Investment Manager and TCW Funds Management,
Inc. ("TCW") be submitted to the Portfolio's shareholders for approval at a
special meeting expected to be held August 4, 1999. Under the proposed
sub-advisory agreement, TCW would serve as sub-advisor to the Portfolio,
providing investment advice and portfolio management services to the Portfolio,
subject to the Investment Manager's supervision. Pursuant to the sub-advisory
agreement, the Investment Manager would pay TCW monthly compensation equal to
40% of the fee the Investment Manager accrues from the Portfolio. Retention of
the sub-advisor would not result in any change in the investment management
fees currently paid by the Portfolio.
A proxy statement detailing the proposed sub-advisory agreement, the
reasons for the Board's action and information concerning TCW will be
distributed to the Portfolio's shareholders.
(b) Changes to Non-Fundamental Policies -- In connection with the
proposed retention of TCW as sub-advisor, the Board unanimously approved
various changes to the Portfolio's non-fundamental investment policies. These
changes are intended to reflect TCW's proposed investment approach to managing
the Portfolio and, thus, will not be implemented unless the Portfolio's
shareholders approve the sub-advisory agreement.
(c) Name Change -- The Board unanimously approved a change in the name
of the Portfolio from "Mid-Cap Growth Portfolio" to "Mid-Cap Equity Portfolio."
Implementation of this change is also subject to approval of the sub-advisory
agreement by the Portfolio's shareholders.
(3) UTILITIES PORTFOLIO
The Board unanimously recommended that the Portfolio's shareholders
approve changing the Portfolio's investment objective to: "seek both capital
appreciation and current income." Currently, the Portfolio's objective is to
"provide current income and long-term growth of income and capital, by
investing primarily in equity and fixed-income securities of companies engaged
in the public utilities industry." Adoption of this change would have the
effect of (i) eliminating long-term growth of income as an objective of the
Portfolio and (ii) permitting the Portfolio to invest primarily in the entire
utilities industry, as opposed to the more limited public utilities industry.
A proxy statement fully describing the proposed change in objective and
the reasons for the Board's action will be distributed to the Portfolio's
shareholders.
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(4) NORTH AMERICAN GOVERNMENT SECURITIES PORTFOLIO AND EMERGING MARKETS
PORTFOLIO
The Board unanimously approved proposed transactions pursuant to which
shares of each of these Portfolios would be redeemed and automatically
reinvested in a comparable fund--the Emerging Markets Equity Fund of Morgan
Stanley Dean Witter Universal Funds, for shares of the Emerging Markets
Portfolio, and the Fixed Income Fund of Morgan Stanley Dean Witter Universal
Funds, for shares of the North American Government Securities Portfolio.
Implementation of each of these proposals is subject to the issuance of an
order by the Securities and Exchange Commission authorizing the proposed
transactions. If the order is granted and the transactions are implemented, the
two Portfolios would be terminated.
April 22, 1999
