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                       MORGAN STANLEY SELECT EQUITY TRUST
            MORGAN STANLEY HIGH-TECHNOLOGY 35 INDEX PORTFOLIO 2001-3
                            REFERENCE TRUST AGREEMENT

     This Reference Trust Agreement dated June 19, 2001 between MORGAN STANLEY
DW INC., as Depositor, and The Bank of New York, as Trustee, sets forth certain
provisions in full and incorporates other provisions by reference to the
document entitled "Morgan Stanley Dean Witter Select Equity Trust, Trust
Indenture and Agreement" (the "Basic Agreement") dated September 30, 1993 as
amended on December 30, 1997. 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 as follows:

     A. The first sentence of Section 2.01 is amended to add the following
language at the end of such sentence: "and/or cash (or a letter of credit in
lieu of cash) with instructions to the Trustee to purchase one or more of such
Securities which cash (or cash in an amount equal to the face amount of the
letter of credit), to the extent not used by the Trustee to purchase such
Securities within the 90-day period following the first deposit of Securities in
the Trust, shall be distributed to Unit Holders on the Distribution Date next
following such 90-day period or such earlier date as the Depositor and the
Trustee determine".

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     B. 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.

     C. The first sentence of Section 2.06 is amended to add the following
language after "Securities"))": "and/or cash (or a letter of credit in lieu of
cash) with instructions to the Trustee to purchase one or more Additional
Securities which cash (or cash in an amount equal to the face amount of the
letter of credit), to the extent not used by the Trustee to purchase such
Additional Securities within the 90-day period following the first deposit of
Securities in the Trust, shall be distributed to Unit Holders on the
Distribution Date next following such 90-day period or such earlier date as the
Depositor and the Trustee determine".

     D. Article III, entitled "Administration of Trust", Section 3.01 Initial
Cost shall be amended as follows:

     Section 3.01 Initial Cost shall be amended to substitute the following
language:

     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 di-

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rected 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.

     E. The third paragraph of Section 3.05 is hereby amended to add the
following sentence after the first sentence thereof: "Depositor may direct the
Trustee to invest the proceeds of any sale of Securities not required for the
redemption of Units in eligible money market instruments selected by the
Depositor which will include only negotiable certificates of deposit or time
deposits of domestic banks which are members of the Federal Deposit Insurance
Corporation and which have, together with their branches or subsidiaries, more
than $2 billion in total assets, except that certificates of deposit or time
deposits of smaller domestic banks may be held provided the deposit does not
exceed the insurance coverage on the instrument (which currently is $100,000),
and provided further that the Trust's aggregate holding of certificates of
deposit or time deposits issued by the Trustee may not ex-

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ceed the insurance coverage of such obligations and U.S. Treasury notes or
bills (which shall be held until the maturity thereof) each of which matures
prior to the earlier of the next following Distribution Date or 90 days after
receipt, the principal thereof and interest thereon (to the extent such interest
is not used to pay Trust expenses) to be distributed on the earlier of the 90th
day after receipt or the next following Distribution Date."

     F. The first sentence of each of Sections 3.10, 3.11 and 3.12 is amended to
insert the following language at the beginning of such sentence, "Except as
otherwise provided in Section 3.13,".

     G. The following new Section 3.13 is added

     Section 3.13. EXTRAORDINARY EVENT-SECURITY RETENTION AND VOTING. In the
event the Trustee is notified of any action to be taken or proposed to be taken
by holders of the securities held by the Trust in connection with any proposed
merger, reorganization, spin-off, split-off or split-up by the issuer of stock
or securities held in the Trust, the Trustee shall take such action or refrain
from taking any action, as appropriate, so as to insure that the securities are
voted as closely as possible in the same manner and in the same general
proportion as are the securities held by owners other than the Trust. If stock
or securities are received by the Trustee, with or without cash, as a result of
any merger, reorganization, spin-off, split-off or split-up by the issuer of
stock or securities held in the Trust, the Trustee at the direction of the
Depositor may retain such stock or securities in the Trust. Neither the
Depositor nor the Trustee shall be liable to any person for any action or
failure to take action with respect to this section.

     H. Section 1.01 is amended to add the following definition: (9) "Deferred
Sales Charge" shall mean any deferred sales charge payable in accordance with
the provisions of Section 3.14 hereof, as set forth in the prospectus for a
Trust. Definitions following this definition (9) shall be renumbered.

     I. Section 3.05 is hereby amended to add the following paragraph after the
end thereof: On each Deferred Sales Charge payment date set forth in the
prospectus for

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a Trust, the Trustee shall pay the account created pursuant to Section 3.14 the
amount of the Deferred Sales Charge payable on each such date as stated in the
prospectus for a Trust. Such amount shall be withdrawn from the Principal
Account from the amounts therein designated for such purpose.

     J. Section 3.06B(3) shall be amended by adding the following: "and any
Deferred Sales Charge paid".

     K. Section 3.08 shall be amended by adding the following at the end
thereof: "In order to pay the Deferred Sales Charge, the Trustee shall sell or
liquidate an amount of Securities at such time and from time to time and in such
manner as the Depositor shall direct such that the proceeds of such sale or
liquidation shall equal the amount required to be paid to the Depositor pursuant
to the Deferred Sales Charge program as set forth in the prospectus for a Trust.

     L. Section 3.14 shall be added as follows:

     Section 3.14. Deferred Sales Charge. If the prospectus for a Trust
specifies a Deferred Sales Charge, the Trustee shall, on the dates specified in
and as permitted by the prospectus, withdraw from the Income Account if such
account is designated in the prospectus as the source of the payments of the
Deferred Sales Charge, or to the extent funds are not available in that account
or if such account is not so designated, from the Principal Account, an amount
per Unit specified in the prospectus and credit such amount to a special,
non-Trust account maintained at the Trustee out of which the Deferred Sales
Charge will be distributed to the Depositor. If the Income Account is not
designated as the source of the Deferred Sales Charge payment or if the balances
in the Income and Principal Accounts are insufficient to make any such
withdrawal, the Trustee shall, as directed by the Depositor, either advance
funds, if so agreed to by the Trustee, in an amount equal to the proposed
withdrawal and be entitled to reimbursement of such advance upon the deposit of
additional monies in the Income Account or the Principal Account, sell
Securities and credit the proceeds thereof to such special Depositor's account
or credit Securities in kind to such special Depositor's Account. Such
directions shall identify the Securities, if any, to be

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sold or distributed in kind and shall contain, if the Trustee is directed by the
Depositor to sell a Security, instructions as to execution of such sales. If a
Unit Holder redeems Units prior to full payment of the Deferred Sales Charge,
the Trustee shall, if so provided in the prospectus, on the Redemption Date,
withhold from the Redemption Price payment to such Unit Holder an amount equal
to the unpaid portion of the Deferred Sales Charge and distribute such amount to
such special Depositor's account or, if the Depositor shall purchase such Unit
pursuant to the terms of Section 5.02 hereof, the Depositor shall pay the
Redemption Price for such Unit less the unpaid portion of the Deferred Sales
Charge. The Depositor may at any time instruct the Trustee to distribute to the
Depositor cash or Securities previously credited to the special Depositor's
account.

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

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

     O. 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.

                                      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 Morgan
Stanley High-Technology 35 Index Portfolio 2001-3 (the "High-Tech 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.

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     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 24,659 for the High-Tech Trust.

     E. A Unit is hereby declared initially equal to 1/24,659th for the
High-Tech Trust.

     F. The term "In-Kind Distribution Date" shall mean August 27, 2002.

     G. The term "Record Dates" shall mean March 1, 2002, and
September 25, 2002 and such other date as the Depositor may direct.

     H. The term "Distribution Dates shall mean March 15, 2002 and on or about
October 2, 2002 and such other date as the Depositor may direct.

     I. The term "Termination Date" shall mean September 25, 2002.

     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 $0.72 per 100 Units.

     L. For a Unit Holder to receive an "in-kind" distribution during the life
of the Trust, such Unit Holder must tender at least 25,000 Units for redemption.
There is no minimum amount of Units that a Unit Holder must tender in order to
receive an "in-kind" distribution on the In-Kind Date or in connection with a
rollover.

     M. The Indenture is amended to provide that the period during which the
Trustee shall liquidate the Trust Securities shall not exceed 20 business days
commencing on the first business day following the In-Kind Date.

               (Signatures and acknowledgments on separate pages)

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     The Schedule of Portfolio Securities in the prospectus included in this
Registration Statement is hereby incorporated by reference herein as Schedule A
hereto.