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                                   Exhibit 4.2



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                 MORGAN STANLEY DEAN WITTER SELECT EQUITY TRUST
            MORGAN STANLEY HIGH-TECHNOLOGY 35 INDEX PORTFOLIO 2001-2

                            REFERENCE TRUST AGREEMENT

                  This Reference Trust Agreement dated       , 2001 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 "Dean Witter Select Equity Trust,  Trust Indenture and
Agreement" (the "Basic  Agreement") dated September 30, 1993. 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

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         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".

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

                           (i) the first part of the first  sentence  of Section
                  3.01 Initial Cost shall be amended to substitute the following
                  language before the phrase "provided, however":

                                    "With respect to the Trust,  the cost of the
                           preparation,    printing   and   execution   of   the
                           Certificates,  Indenture,  Registration Statement and
                           other  documents  relating to the Trust,  Federal and
                           State  registration  fees and costs, the initial fees
                           and  expenses  of the  Trustee,  legal  and  auditing
                           expenses  and  other   out-of-pocket   organizational
                           expenses,  to the  extent  not borne by the  Sponsor,
                           shall be paid by the Trust;"

                   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

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         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 3.12 hereof, as
         set forth in the prospectus for a Trust.  Definitions following this
         definition (9) shall be renumbered.

                  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  3.12 the amount of the  Deferred
         Sales Charge  payable on each such date as stated in the prospectus for

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         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 3.12 shall be added as follows:

                  Section 3.12.  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

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         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.

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

                                       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 Morgan Stanley  High-Technology 35 Index Portfolio 2001-2
          (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.

               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          for the High-Tech Trust.

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

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

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

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

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

               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.

               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. The  Indenture  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)