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                 MORGAN STANLEY DEAN WITTER SELECT EQUITY TRUST
                        SELECT GLOBAL 30 PORTFOLIO 2000-3
                            REFERENCE TRUST AGREEMENT


         This Reference Trust Agreement dated June 29, 2000 between DEAN WITTER
REYNOLDS 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".

                  B. 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".


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                  C. 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 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,


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                  used for payment of redemptions in excess of the per-Unit
                  amount allocable to Units tendered for redemption.

                  D. 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 exceed 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."

                  E. 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,".

                  F. 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.

                  G. 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.


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                  H. 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 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.

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

                  J. 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.

                  K. 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 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 dis-


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         tribute to the Depositor cash or Securities previously credited to
         the special Depositor's account.

                  L.       The following new Section 3.15 is added:

                  Section 3.15. FOREIGN EXCHANGE TRANSACTIONS; RECLAIMING
         FOREIGN TAXES. (a) For any Trust holding Securities denominated in a
         currency other than U.S. dollars, the Depositor shall direct the
         Trustee with respect to the circumstances under which foreign exchange
         transactions are to be entered into and calculations under this
         Indenture are to be made, in order to convert amounts receivable in
         respect of the Securities in foreign currencies into U.S. dollars.

                  (b) The Trustee shall take such reasonable action as the
         Depositor shall direct or, if not so directed, use reasonable efforts
         to reclaim or recoup any amounts of non-U.S. tax paid by the Trust or
         withheld from income received by the Trust to which the Trust may be
         entitled as a refund.

                  M. The following paragraphs are inserted after the first
         paragraph in Section 4.01:

                  "With respect to foreign securities, each security listed on a
                  securities exchange will be valued at the last closing sale
                  price on the relevant stock exchange or if no such price
                  exists at the closing offer price thereof.

                  If the Trust holds securities denominated in a currency other
                  than U.S. dollars, the evaluations shall be converted to U.S.
                  dollars based, during the initial offering period, on the
                  offering side of the relevant currency exchange rate, and,
                  subsequent to such period, on the bid side of the relevant
                  exchange rate, including the cost of a forward foreign
                  exchange contract in the relevant currency to correspond to
                  the Trustee's settlement requirement for redemption requests
                  as quoted to the Trustee by one or more banks designated by
                  the Depositor, unless the Security is in the form of an
                  American depository share or receipt, in which case the
                  evaluations shall be based upon the U.S. dollar prices in the
                  market for American depository shares or receipts (unless the
                  Trustee deems such prices inappropriate as a basis for
                  valuation)."

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


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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 Dean Witter Select
         Equity Trust Select Global 30 Portfolio 2000-3 (the "Select 30 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 Dean Witter Reynolds Inc.

                  D. The aggregate number of Units referred to in Sections 2.03
         and 9.01 of the Basic Agreement is 24,498 for the Select 30 Trust.


                  E. A Unit is hereby declared initially equal to 1/24,498.


                  F. The term "In-Kind Distribution Date" shall mean
         September 11, 2001.



                  G. The term "Record Dates" shall mean March 1, 2001,
         and October 1, 2001 and such other date as the Depositor may direct.



                  H. The term "Distribution Dates shall mean March 15, 2001,
         and on or about October 8, 2001, and such other date as the
         Depositor may direct.



                  I. The term "Termination Date" shall mean October 1, 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 $0.80 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.

                  (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.