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                       MORGAN STANLEY SELECT EQUITY TRUST
                           HEALTHCARE PORTFOLIO 2001-3
                            REFERENCE TRUST AGREEMENT

          This Reference Trust Agreement dated            , 2001 between MORGAN
STANLEY DW INC., as Depositor, and The Chase Manhattan Bank, as Trustee, sets
forth certain provisions in full and incorporates other provisions by
reference to the document entitled "Sears Equity Investment Trust, Trust
Indenture and Agreement" dated January 22, 1991, as amended on March 16, 1993
and July 18, 1995 (the "Basic Agreement"). Such provisions as are
incorporated by reference constitute a single instrument (the "Indenture").

                                WITNESSETH THAT:

          In consideration of the premises and of the mutual agreements herein
contained, the Depositor and the Trustee agree as follows:

                                       I.

                     STANDARD TERMS AND CONDITIONS OF TRUST

          Subject to the provisions of Part II hereof, all the provisions
contained in the Basic Agreement are herein incorporated by reference in their
entirety and shall be deemed to be a part of this instrument as fully and to the
same extent as though said provisions had been set forth in full in this
instrument except that the Basic Agreement is hereby amended in the following
manner:

          A. Article I, Section 1.01, paragraph (29) defining "Trustee" shall be
     amended as follows:

          "'Trustee' shall mean The Chase Manhattan Bank, or any successor
          trustee appointed as hereinafter provided."

          B. Reference to United States Trust Company of New York in its
     capacity as Trustee is replaced by The Chase Manhattan Bank throughout the
     Basic Agreement.

          C. Reference to "Morgan Stanley Dean Witter Select Equity Trust" is
     replaced by "Morgan Stanley Select Equity Trust".

          D. Section 3.01 is amended to substitute the following:

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          Section 3.01. INITIAL COST The costs of organizing the Trust and sale
     of the Trust Units shall, to the extent of the expenses reimbursable to the
     Depositor provided below, be borne by the Unit Holders, PROVIDED, HOWEVER,
     that, to the extent all of such costs are not borne by Unit Holders, the
     amount of such costs not borne by Unit Holders shall be borne by the
     Depositor and, PROVIDED FURTHER, HOWEVER, that the liability on the part of
     the Depositor under this section shall not include any fees or other
     expenses incurred in connection with the administration of the Trust
     subsequent to the deposit referred to in Section 2.01. Upon notification
     from the Depositor that the primary offering period is concluded, the
     Trustee shall withdraw from the Account or Accounts specified in the
     Prospectus or, if no Account is therein specified, from the Principal
     Account, and pay to the Depositor the Depositor's reimbursable expenses of
     organizing the Trust and sale of the Trust Units in an amount certified to
     the Trustee by the Depositor. If the balance of the Principal Account is
     insufficient to make such withdrawal, the Trustee shall, as directed by the
     Depositor, sell Securities identified by the Depositor, or distribute to
     the Depositor Securities having a value, as determined under Section 4.01
     as of the date of distribution, sufficient for such reimbursement. The
     reimbursement provided for in this section shall be for the account of the
     Unitholders of record at the conclusion of the primary offering period and
     shall not be reflected in the computation of the Unit Value prior thereto.
     As used herein, the Depositor's reimbursable expenses of organizing the
     Trust and sale of the Trust Units shall include the cost of the initial
     preparation and typesetting of the registration statement, prospectuses
     (including preliminary prospectuses), the indenture, and other documents
     relating to the Trust, SEC and state blue sky registration fees, the cost
     of the initial valuation of the portfolio and audit of the Trust, the
     initial fees and expenses of the Trustee, and legal and other out-of-
     pocket expenses related thereto, but not including the expenses incurred in
     the printing of preliminary prospectuses and prospectuses, expenses
     incurred in the preparation and printing of brochures and other advertising
     materials and any other selling expenses. Any cash which the Depositor has
     identified as to be used for reimbursement of expenses pursuant to this
     Section shall be reserved by the Trustee for such purpose and shall not be
     subject to distribution or, unless the Depositor otherwise directs, used
     for payment of redemptions in excess of the per-Unit amount allocable to
     Units tendered for redemption.

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          E.   Reference to "Dean Witter Reynolds Inc." is
     replaced by "Morgan Stanley DW Inc."

          F.   Section 2.03 is amended to add the following to the end of the
     first paragraph thereof. The number of Units may be increased through a
     split of the Units of decreased through a reverse split thereof, as
     directed by the Depositor, which revised number of Units shall be recorded
     by Trustee on its books.

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                                       II.

                      SPECIAL TERMS AND CONDITIONS OF TRUST

          The following special terms and conditions are hereby agreed to:

          A. The Trust is denominated Morgan Stanley Select Equity Trust
Healthcare Portfolio 2001-3 (the " Healthcare Trust").

          B. The publicly traded stocks listed in Schedule A hereto are those
which, subject to the terms of this Indenture, have been or are to be deposited
in trust under this Indenture.

          C. The term, "Depositor" shall mean Morgan Stanley DW Inc.

          D. The aggregate number of Units referred to in Sections 2.03 and 9.01
of the Basic Agreement is                 for the Healthcare Trust.

          E. A Unit is hereby declared initially equal to 1/          th for the
Healthcare Trust.

          F. The term "In-Kind Distribution Date" shall mean
          , 2002.

          G. The term "Record Dates" shall mean          , 2001,           ,
2001,            , 2001 and         , 2001 and such other date as the Depositor
may direct.

          H. The term "Distribution Dates shall mean         ,
2001,          , 2001,           , 2001 and             , 2001 and such other
date as the Depositor may direct.

          I. The term "Termination Date" shall mean           ,
2001.

          J. The Depositor's Annual Portfolio Supervision Fee shall be a maximum
of $0.25 per 100 Units.

          K. The Trustee's annual fee as defined in Section 6.04 of the
Indenture shall be $            per 100 Units if the greatest number of Units
outstanding during the period is 10,000,000 or more; $          per 100 Units if
the greatest number of Units outstanding during the period is between 5,000,000
and 9,999,999; and $        per 100 Units if the greatest number of Units
outstanding during the period is 4,999,999 or less.
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          L. For a Unit Holder to receive "in-kind" distribution during the life
of the Trust other than in connection with a rollover, such Unit Holder must
tender at least 25,000 Units for redemption. On the In-Kind Date there is no
minimum amount of Units that a Unit Holder must tender in order to receive an
"in-kind" distribution.

          M. Paragraph (b)(ii) of Section 9.03 is amended to provide that the
period during which the Trustee shall liquidate the Trust Securities shall not
exceed 14 business days commencing on the first business day following the
In-Kind Date.

               (Signatures and acknowledgments on separate pages)