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Filed Pursuant to Rule 497(e)
Registration File No.: 333-43135
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER MID-CAP DIVIDEND GROWTH SECURITIES
DATED JUNE 30, 1999
On January 26, 2000, the Board of Trustees of Morgan Stanley Dean Witter
Mid-Cap Dividend Growth Securities (the "Fund") approved an Agreement and Plan
of Reorganization by and between the Fund and Morgan Stanley Dean Witter
Mid-Cap Equity Trust ("Mid-Cap Equity"), pursuant to which substantially all of
the assets of the Fund would be combined with those of Mid-Cap Equity and
shareholders of the Fund would become shareholders of Mid-Cap Equity receiving
shares of Mid-Cap Equity equal to the value of their holdings in the Fund (the
"Reorganization"). Each shareholder of the Fund will receive the Class of
shares of Mid-Cap Equity that corresponds to the Class of shares of the Fund
currently held by that shareholder. The Reorganization is subject to the
approval of shareholders of the Fund at a special meeting of shareholders
scheduled to be held on June 22, 2000. A proxy statement formally detailing the
proposal, the reasons for the Trustees' action and information concerning
Mid-Cap Equity will be distributed to shareholders of the Fund.
January 26, 2000
