EXHIBIT 4.1




                             FIXED RATE SENIOR NOTE

     REGISTERED                                              REGISTERED
     No. FXR                                                 U.S.$13,000,000
                                                             CUSIP: 617446GQ6


     Unless this certificate is presented by an authorized representative of
The Depository Trust Company (55 Water Street, New York, New York) to the
issuer or its agent for registration of transfer, exchange or payment, and any
certificate issued is registered in the name of Cede & Co. or such other name
as requested by an authorized representative of The Depository Trust Company
and any payment is made to Cede & Co., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF
FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL since the registered
owner hereof, Cede & Co., has an interest herein.






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                                         MORGAN STANLEY DEAN WITTER & CO.
                                     SENIOR GLOBAL MEDIUM-TERM NOTE, SERIES C
                                                   (Fixed Rate)

                                     0.25% EXCHANGEABLE NOTE DUE MAY 30, 2008
                                   (EXCHANGEABLE FOR SHARES OF COMMON STOCK OF
                                              SIX SOFTWARE COMPANIES)

<TABLE>
<S>                           <C>                           <C>                         <C>
===================================================================================================================
ORIGINAL ISSUE DATE:          INITIAL REDEMPTION           INTEREST RATE:               MATURITY DATE:
     May 30, 2001                  DATE: See "MSDW              0.25% per annum              May 30, 2008
                                   Call Right" below
-------------------------------------------------------------------------------------------------------------------
INTEREST ACCRUAL              INITIAL REDEMPTION           INTEREST PAYMENT             OPTIONAL REPAYMENT
     DATE: May 30, 2001            PERCENTAGE:                  DATE(S): Each May            DATE(S): N/A
                                   100% . See also              30 and November 30,
                                   "MSDW Call Right"            beginning November
                                   below                        30, 2001
-------------------------------------------------------------------------------------------------------------------
SPECIFIED CURRENCY:           ANNUAL REDEMPTION            INTEREST PAYMENT             APPLICABILITY OF
     U.S. Dollars                  PERCENTAGE                   PERIOD:  Semi-               MODIFIED
                                   REDUCTION: N/A               annually                     PAYMENT UPON
                                                                                             ACCELERATION:
                                                                                             See "Alternate
                                                                                             Calculation in case of
                                                                                             an Event of Default"
                                                                                             below
-------------------------------------------------------------------------------------------------------------------
IF SPECIFIED                  REDEMPTION NOTICE            APPLICABILITY OF             If yes, state Issue Price:
     CURRENCY                      PERIOD: N/A                  ANNUAL
     OTHER THAN                                                 INTEREST
     U.S. DOLLARS,                                              PAYMENTS: N/A
     OPTION TO
     ELECT
     PAYMENT IN
     U.S. DOLLARS:
     N/A
-------------------------------------------------------------------------------------------------------------------
EXCHANGE RATE                 TAX REDEMPTION AND                                        ORIGINAL YIELD TO
     AGENT: N/A               PAYMENT OF                                                     MATURITY: N/A
                              ADDITIONAL
                              AMOUNTS: No
-------------------------------------------------------------------------------------------------------------------
OTHER PROVISIONS:             If yes, state Initial Offering
     See below                Date: N/A
===================================================================================================================
</TABLE>

Initial Basket Value......     $761.035

Basket Value..............     The Basket Value, for any date, shall equal the
                               sum of the products of the Market Price and the
                               Exchange Ratio for


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                               each Basket Stock, each determined as of such
                               date by the Calculation Agent.

Basket....................     The Basket is a weighted portfolio of the six
                               Basket Stocks consisting of a number of shares
                               of each Basket Stock equal to the Exchange Ratio
                               with respect to the Basket Stock. See "Basket
                               Stocks" below.

                               The Exchange Ratio for each Basket Stock is a
                               number of shares calculated so that each Basket
                               Stock represents an equal proportion of the
                               Initial Basket Value at the time of pricing on
                               May 24, 2001.

Basket Stocks.............     The Basket Stocks are the six stocks set forth in
                               the table below. The table also indicates the
                               ticker symbol for each Basket Stock on the
                               Nasdaq National Market, the proportion of the
                               Initial Basket Value represented by the shares
                               of each Basket Stock contained in the Basket,
                               the Exchange Ratio with respect to each Basket
                               Stock, the initial price of each Basket Stock,
                               and the aggregate value of the shares of each
                               Basket Stock contained in the Basket, each as of
                               the time of pricing on May 24, 2001.

                                                            Proportion
                                                            of Initial
        Issuer of              Ticket   Ticker   Exchange     Basket     Initial
        Basket Stock           Symbol   Value      Ratio      Stock       Value
        ------------           -------  ------   --------   ----------   -------
        Siebel Systems, Inc.    SEBL    1/6th    2.372599     $53.46     $126.84
        Check Point Software
           Technologies Ltd.    CHKP    1/6th    2.011405     $63.06     $126.84
        Symantec Corporation    SYMC    1/6th    1.815619     $69.86     $126.84
        VERITAS Software
           Corporation          VRTS    1/6th    1.688712     $75.11     $126.84
        Rational Software
           Corporation          RATL    1/6th    4.743424     $26.74     $126.84
        PeopleSoft, Inc.        PSFT    1/6th    2.982346     $42.53     $126.84


Exchange Ratio............     The Exchange Ratio for each Basket Stock is set
                               forth in the table above, subject to adjustment
                               for certain corporate events relating to the
                               issuer of that Basket Stock. See "Adjustments to
                               the Exchange Ratios and Basket" below.

Exchange Right............     On any Exchange Date, subject to a prior call of
                               this Note for cash in an amount equal to the
                               Call Price by the Issuer as described under
                               "MSDW Call Right" below, the holder of this Note
                               shall be entitled, upon completion by the


                                      A-3

<PAGE>


                               holder and delivery to the Issuer and the
                               Calculation Agent of an Official Notice of
                               Exchange (in the form of Annex A attached
                               hereto) prior to 11:00 a.m. New York City time
                               on such date, to exchange each $1,000 principal
                               amount of this Note for a number of shares of
                               each Basket Stock equal to its Exchange Ratio,
                               subject to any adjustment (x) to the Exchange
                               Ratio or (y) in the stock, other securities or
                               other property or assets (including, without
                               limitation, cash or other classes of stock of
                               the issuer of such Basket Stock) ("Other
                               Exchange Property") to be delivered instead of
                               or in addition to such Basket Stock as a result
                               of any corporate event described under
                               "Adjustments to the Exchange Ratio and the
                               Basket" below, in each case, required to be made
                               prior to the close of business on the second
                               Business Day after any such Exchange Date. Upon
                               any such exchange, the Issuer may, at its sole
                               option, either deliver such Basket Stock (or
                               such Other Exchange Property to be delivered
                               instead of or in addition to such Basket Stock
                               as aforesaid) or pay an amount in cash for each
                               $1,000 principal amount of this Note equal to
                               the Basket Value as of the close of business on
                               such Exchange Date, as determined by the
                               Calculation Agent, in lieu of such Basket Stock
                               (or such Other Exchange Property). Such delivery
                               or payment shall be scheduled to be made 3
                               Business Days after any Exchange Date, subject
                               to delivery of this Note to the Trustee on such
                               day (such third Business Day or, if later, the
                               day on which this Note is actually delivered to
                               the Trustee and all conditions of the exchange
                               are fulfilled, the "Exchange Settlement Date.")
                               Upon any exercise of the Exchange Right, the
                               holder of this exchanged Note shall not be
                               entitled to receive any cash payment
                               representing any accrued but unpaid interest on
                               this Note. Consequently, if this Note is
                               exchanged so that the Exchange Settlement Date
                               occurs during the period from the close of
                               business on a Record Date (as defined below) for
                               the payment of interest and prior to the next
                               succeeding Interest Payment Date, this Note
                               must, as a condition to the delivery of the
                               Basket Stocks or cash, be accompanied by funds
                               equal to the interest payable on such succeeding
                               Interest Payment Date on the principal amount so
                               exchanged.

                               Prior to 9:30 a.m. on the first Business Day
                               immediately succeeding any Exchange Date, the
                               Issuer shall cause the Calculation Agent to
                               provide written notice to the Trustee



                                      A-4

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                               at its New York office and to The Depository
                               Trust Company, or any successor depositary
                               ("DTC"), on which notice the Trustee and DTC may
                               conclusively rely, (i) of its receipt of any
                               such "Official Notice of Exchange," (ii) of the
                               Issuer's determination to deliver shares of the
                               Basket Stocks (or, if applicable, any Other
                               Exchange Property to be delivered as a result of
                               any corporate event described in paragraphs 5, 6
                               or 7 under "Adjustments to the Exchange Ratios
                               and the Basket" below) or to pay an equivalent
                               amount of cash for each $1,000 principal amount
                               of this Note and (iii) if the Basket Stocks are
                               to be delivered (or, if applicable, any Other
                               Exchange Property) of the number of shares of
                               such Basket Stocks (or the amount of such Other
                               Exchange Property), and of the amount of any
                               cash to be paid in lieu of fractional shares of
                               such Basket Stocks (or of any other securities
                               included in Other Exchange Property, if
                               applicable) or, if cash is to be paid, of the
                               amount of such cash for each $1,000 principal
                               amount of this Note. If, as a result of any
                               corporate event described under "Adjustments to
                               the Exchange Ratios and the Basket" occurring
                               during the period from and including the
                               Exchange Date to but excluding the Exchange
                               Settlement Date the Calculation Agent makes any
                               adjustment to the Exchange Ratio with respect to
                               any Basket Stock and consequent adjustment to
                               the number of shares of such Basket Stock to be
                               delivered or any adjustment to the quantity of
                               any Other Exchange Property due to the holder of
                               this Note, the Calculation Agent shall give
                               prompt notice of any such adjustments to the
                               Trustee at its New York office and to DTC, on
                               which notice the Trustee may conclusively rely.
                               No adjustments to the Exchange Ratio will be
                               made after the Exchange Date if the Issuer has
                               given notice that it will deliver cash for each
                               $1,000 principal amount of this Note.

                               The Issuer shall, or shall cause the Calculation
                               Agent to, deliver any such Basket Stocks (or any
                               Other Exchange Property) or such cash to the
                               Trustee for delivery to the holders.

Record Date..............      The Record Date for each Interest Payment Date
                               (other than the Maturity Date) will be the close
                               of business on the date 15 calendar days prior
                               to such Interest Payment Date, whether or not
                               that date is a Business Day.



                                      A-5

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No Fractional Shares .....     If upon any exchange of this Note the Issuer
                               chooses to deliver the Basket Stocks (and, if
                               applicable, any other stock or other securities),
                               the Issuer shall pay cash in lieu of delivering
                               fractional shares of any Basket Stock (and, if
                               applicable, of any other stock or securities) in
                               an amount equal to the corresponding fractional
                               Market Price of such fraction of a share of such
                               Basket Stock (or, if applicable, of such other
                               stock or other securities) as determined by the
                               Calculation Agent as of either (i) such Exchange
                               Date, (ii) the second Trading Day prior to the
                               Call Date or (iii) in the event of a subsequent
                               adjustment to Exchange Ratio, as of the date of
                               such adjustment, as applicable.

Exchange Date.............     Any Trading Day on which a holder satisfies the
                               conditions to exchanging the Notes as described
                               under "Exchange Right" above; provided that such
                               Trading Day falls during the period beginning
                               June 30, 2001 and ending on the day prior to the
                               earliest of (i) the fifth scheduled Trading Day
                               prior to the Maturity Date, (ii) the fifth
                               scheduled Trading Day prior to the Call Date and
                               (iii) in the event of a call for the cash Call
                               Price as described under "--MSDW Call Right"
                               below, the last scheduled Trading Day prior to
                               the MSDW Notice Date.

MSDW Call Right ..........     On or after May 30, 2003, the Issuer may call
                               this Note, in whole but not in part, for
                               mandatory exchange into each Basket Stock (and,
                               if applicable, any Other Exchange Property) at
                               the applicable Exchange Ratio; provided that, if
                               the Basket Value on the Trading Day immediately
                               preceding the MSDW Notice Date, as determined by
                               the Calculation Agent, is less than the Call
                               Price, the Issuer shall (under those
                               circumstances only) pay the Call Price in cash
                               on the Call Date.

                               On or after the MSDW Notice Date, unless the
                               Issuer has called this Note for cash, the holder
                               of this Note shall continue to be entitled to
                               exercise the Exchange Right and receive any
                               amounts described under "Exchange Right" above.

                               On the MSDW Notice Date, the Issuer shall give
                               notice of the Issuer's exercise of the MSDW Call
                               Right (i) to the holder of this Note by mailing
                               notice of such exercise by first class mail,
                               postage prepaid, at least 30 days and not


                                      A-6

<PAGE>



                               more than 60 days prior to the date (the "Call
                               Date") on which the Issuer shall effect such
                               exchange at the holder's last address as it
                               shall appear upon the registry books, (ii) to
                               the Trustee by telephone or facsimile confirmed
                               by mailing such notice to the Trustee by first
                               class mail, postage prepaid, at its New York
                               office and (iii) to DTC in accordance with the
                               applicable procedures set forth in the Letter of
                               Representations related to this Note. Any notice
                               which is mailed in the manner herein provided
                               shall be conclusively presumed to have been duly
                               given, whether or not the holder of this Note
                               receives the notice. Failure to give notice by
                               mail, or any defect in the notice to the holder
                               of any Note shall not affect the validity of the
                               proceedings for the exercise of the MSDW Call
                               Right with respect to any other Note.

                               The notice of the Issuer's exercise of the MSDW
                               Call Right shall specify (i) the Call Date, (ii)
                               whether the Basket Value on the Trading Day
                               immediately prior to the MSDW Notice Date, as
                               determined by the Calculation Agent, is less
                               than the Call Price so that the Issuer will pay
                               the Call Price in cash on the Call Date, (iii)
                               the place or places of payment in cash (in the
                               event of a call for the Call Price) or, if the
                               Basket Value on the Trading Day immediately
                               prior to the MSDW Notice Date, as determined by
                               the Calculation Agent, is equal to or greater
                               than the Call Price, the place or places of
                               delivery of the Basket Stocks, and, if
                               applicable, of any Other Exchange Property to be
                               delivered as a result of any corporate event
                               described in paragraphs 5, 6 or 7 under
                               "Adjustments to the Exchange Ratios and the
                               Basket" (and of any cash to be paid in lieu of
                               fractional shares of any Basket Stock (and, if
                               applicable, of any such other stock or
                               securities)), (iv) the number of shares of each
                               Basket Stock (and, if applicable, the quantity
                               of any Other Exchange Property) to be delivered
                               per $1,000 principal amount of this Note, (v)
                               that such delivery will be made upon
                               presentation and surrender of this Note and (vi)
                               that such exchange is pursuant to the MSDW Call
                               Right.

                               The notice of the Issuer's exercise of the MSDW
                               Call Right shall be given by the Issuer or, at
                               the Issuer's request, by the Trustee in the name
                               and at the expense of the Issuer.




                                       A7

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                               If the Basket Stocks (and, if applicable, any
                               Other Exchange Property) are to be delivered
                               and, as a result of any corporate event
                               described under "Adjustments to the Exchange
                               Ratios and the Basket" occurring during the
                               period from and including the MSDW Notice Date
                               to the close of business on the second Business
                               Day prior to the Call Date, the Calculation
                               Agent makes any adjustment to any Exchange Ratio
                               of any Basket Stock and consequent adjustment to
                               the number of shares of such Basket Stock to be
                               delivered or any adjustment to the quantity of
                               any Other Exchange Property due to the holder of
                               this Note, the Calculation Agent shall give
                               prompt notice of any such adjustments to the
                               Trustee at its New York office and to DTC, on
                               which notice the Trustee and DTC may
                               conclusively rely. No adjustment to any Exchange
                               Ratio shall be made as a result of any corporate
                               event occurring after the close of business on
                               the second Business Day prior to the Call Date.

                               If this Note is so called for mandatory exchange
                               by the Issuer, then, unless the holder
                               subsequently exercises his Exchange Right (the
                               exercise of which shall not be available to the
                               holder following a call for cash in an amount
                               equal to the Call Price), the Basket Stocks
                               (and, if applicable, any Other Exchange
                               Property) or (in the event of a call for cash,
                               as described above) cash to be delivered to the
                               holder of this Note shall be delivered on the
                               Call Date fixed by the Issuer and set forth in
                               its notice of its exercise of the MSDW Call
                               Right, upon delivery of this Note to the
                               Trustee. The Issuer shall, or shall cause the
                               Calculation Agent to, deliver such shares of the
                               Basket Stocks or cash to the Trustee for
                               delivery to the holders.

                               If this Note is not surrendered for exchange on
                               the Call Date, it shall be deemed to be no
                               longer Outstanding under, and as defined in, the
                               Senior Indenture (as defined below) after the
                               Call Date, except with respect to the holder's
                               right to receive the Basket Stocks (and, if
                               applicable, any Other Exchange Property) or cash
                               due in connection with the MSDW Call Right.

MSDW Notice Date..........     The scheduled Trading Day on which the Issuer
                               issues its notice of mandatory exchange, which
                               must be at least 30 but no more than 60 days
                               prior to the Call Date.



                                      A-8

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Call Date.................     The scheduled Trading Day on or after May 30,
                               2003 specified by the Issuer in its notice of
                               mandatory exchange on which the Issuer shall
                               deliver the Basket Stocks or cash to the holder
                               of this Note for mandatory exchange.

Call Price................     $1,000 per $1,000 principal amount of this Note.

Market Price..............     If a Basket Stock (or any other security for
                               which a Market Price must be determined) is
                               listed on a national securities exchange, is a
                               security of the Nasdaq National Market or is
                               included in the OTC Bulletin Board Service ("OTC
                               Bulletin Board") operated by the National
                               Association of Securities Dealers, Inc. (the
                               "NASD"), the Market Price for one share of such
                               Basket Stock (or one unit of any such other
                               security) on any Trading Day means (i) the last
                               reported sale price, regular way, of the
                               principal trading session on such day on the
                               principal United States securities exchange
                               registered under the Securities Exchange Act of
                               1934, as amended (the "Exchange Act"), on which
                               such Basket Stock (or any such other security)
                               is listed or admitted to trading or (ii) if not
                               listed or admitted to trading on any such
                               securities exchange or if such last reported
                               sale price is not obtainable (even if such
                               Basket Stock (or other such security) is listed
                               or admitted to trading on such securities
                               exchanges), the last reported sale price of the
                               principal trading session on the
                               over-the-counter market as reported on the
                               Nasdaq National Market or OTC Bulletin Board on
                               such day. If the last reported sale price of the
                               principal trading session is not available
                               pursuant to clause (i) or (ii) of the preceding
                               sentence because of a Market Disruption Event or
                               otherwise, the Market Price for any Trading Day
                               shall be the mean, as determined by the
                               Calculation Agent, of the bid prices for such
                               Basket Stock (or any such other security)
                               obtained from as many dealers in such security,
                               but not exceeding three, as shall make such bid
                               prices available to the Calculation Agent. Bids
                               of MS & Co. or any of its affiliates may be
                               included in the calculation of such mean, but
                               only to the extent that any such bid is the
                               highest of the bids obtained. A "security of the
                               Nasdaq National Market" shall include a security
                               included in any successor to such system and the
                               term "OTC Bulletin Board Service" shall include
                               any successor service thereto.



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Trading Day...............     A day, as determined by the Calculation Agent, on
                               which trading is generally conducted on the New
                               York Stock Exchange, Inc. ("NYSE"), the American
                               Stock Exchange LLC, the Nasdaq National Market,
                               the Chicago Mercantile Exchange and the Chicago
                               Board of Options Exchange and in the
                               over-the-counter market for equity securities in
                               the United States and on which a Market
                               Disruption Event (as defined below) has not
                               occurred.

Calculation Agent.........     Morgan Stanley & Co. Incorporated and its
                               successors ("MS & Co.")

Adjustments to the Exchange
Ratios and Basket.........     The Exchange Ratio with respect to any Basket
                               Stock and the Basket shall be adjusted as
                               follows:

                               1. If a Basket Stock is subject to a stock split
                               or reverse stock split, then once such split has
                               become effective, the Exchange Ratio for such
                               Basket Stock shall be adjusted to equal the
                               product of the prior Exchange Ratio and the
                               number of shares issued in such stock split or
                               reverse stock split with respect to one share of
                               such Basket Stock.

                               2. If a Basket Stock is subject (i) to a stock
                               dividend (issuance of additional shares of such
                               Basket Stock) that is given ratably to all
                               holders of shares of such Basket Stock or (ii)
                               to a distribution of such Basket Stock as a
                               result of the triggering of any provision of the
                               corporate charter of the issuer of the Basket
                               Stock, then once the dividend has become
                               effective and such Basket Stock is trading
                               ex-dividend, the Exchange Ratio for such Basket
                               Stock shall be adjusted so that the new Exchange
                               Ratio shall equal the prior Exchange Ratio plus
                               the product of (i) the number of shares issued
                               with respect to one share of such Basket Stock
                               and (ii) the prior Exchange Ratio for such
                               Basket Stock.

                               3. There shall be no adjustments to any Exchange
                               Ratio to reflect cash dividends or other
                               distributions paid with respect to a Basket
                               Stock other than distributions described in
                               paragraph 6 below and Extraordinary Dividends as
                               described below. A cash dividend or other
                               distribution with respect to a Basket Stock
                               shall be deemed to be an "Extraordinary
                               Dividend" if such dividend or other distribution
                               exceeds the immediately


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                               preceding non-Extraordinary Dividend for such
                               Basket Stock (as adjusted for any subsequent
                               corporate event requiring an adjustment
                               hereunder, such as a stock split or reverse
                               stock split) by an amount equal to at least 10%
                               of the Market Price of the Basket Stock on the
                               Trading Day preceding the ex-dividend date for
                               the payment of such Extraordinary Dividend (the
                               "ex-dividend date"). If an Extraordinary
                               Dividend occurs with respect to a Basket Stock,
                               the Exchange Ratio with respect to such Basket
                               Stock shall be adjusted on the ex-dividend date
                               with respect to such Extraordinary Dividend so
                               that the new Exchange Ratio shall equal the
                               product of (i) the then current Exchange Ratio
                               and (ii) a fraction, the numerator of which is
                               the Market Price of the Basket Stock on the
                               Trading Day preceding the ex-dividend date, and
                               the denominator of which is the amount by which
                               the Market Price on the Trading Day preceding
                               the ex-dividend date exceeds the Extraordinary
                               Dividend Amount. The "Extraordinary Dividend
                               Amount" with respect to an Extraordinary
                               Dividend for a Basket Stock shall equal (i) in
                               the case of cash dividends or other
                               distributions that constitute quarterly
                               dividends, the amount per share of such
                               Extraordinary Dividend minus the amount per
                               share of the immediately preceding
                               non-Extraordinary Dividend for such Basket Stock
                               or (ii) in the case of cash dividends or other
                               distributions that do not constitute quarterly
                               dividends, the amount per share of such
                               Extraordinary Dividend. To the extent an
                               Extraordinary Dividend is not paid in cash, the
                               value of the non-cash component shall be
                               determined by the Calculation Agent, whose
                               determination shall be conclusive. A
                               distribution on a Basket Stock described in
                               paragraph 6 below that also constitutes an
                               Extraordinary Dividend shall only cause an
                               adjustment to the Exchange Ratio for such Basket
                               Stock pursuant to paragraph 6.

                               4. If the issuer of a Basket Stock is being
                               liquidated or is subject to a proceeding under
                               any applicable bankruptcy, insolvency or other
                               similar law, this Note shall continue to be
                               exchangeable into such Basket Stock so long as a
                               Market Price for such Basket Stock is available.
                               If a Market Price is no longer available for
                               such Basket Stock for whatever reason, including
                               the liquidation of the issuer of such Basket
                               Stock or the subjection of the issuer of such
                               Basket Stock to a proceeding under any
                               applicable


                                      A-11

<PAGE>



                               bankruptcy, insolvency or other similar law,
                               then the value of such Basket Stock shall equal
                               zero for so long as no Market Price is
                               available.

                               5. If there occurs any reclassification or
                               change with respect to a Basket Stock,
                               including, without limitation, as a result of
                               the issuance of tracking stock by the issuer of
                               such Basket Stock, or if the issuer of such
                               Basket Stock has been subject to a merger,
                               combination or consolidation and is not the
                               surviving entity, or if there occurs a sale or
                               conveyance to another corporation of the
                               property and assets of the issuer of such Basket
                               Stock as an entirety or substantially as an
                               entirety, in each case as a result of which the
                               holders of such Basket Stock shall be entitled
                               to receive stock, other securities or other
                               property or assets (including, without
                               limitation, cash or other classes of stock of
                               the issuer of such Basket Stock) ("Exchange
                               Property") with respect to or in exchange for
                               such Basket Stock, then with respect to such
                               Basket Stock the holders of this Note shall be
                               entitled thereafter to exchange this Note into
                               the kind and amount of Exchange Property that
                               the holder would have owned or been entitled to
                               receive upon such reclassification, change,
                               merger, combination, consolidation, sale or
                               conveyance had the holder exchanged this Note at
                               the then current Exchange Ratio for such Basket
                               Stock immediately prior to any such corporate
                               event, but without interest thereon. At such
                               time, no adjustment will be made to the Exchange
                               Ratio. In the event the Exchange Property
                               consists of securities, those securities shall,
                               in turn, be subject to the antidilution
                               adjustments set forth in paragraphs 1 through 7.

                               6. If the issuer of a Basket Stock issues to all
                               of its shareholders equity securities of an
                               issuer other than the issuer of such Basket
                               Stock (other than in a transaction described in
                               paragraph 5 above), then the holder of this Note
                               shall be entitled to receive such new equity
                               securities upon exchange of this Note. The
                               Exchange Ratio for such new equity securities
                               shall equal the product of the Exchange Ratio in
                               effect for such Basket Stock at the time of the
                               issuance of such new equity securities times the
                               number of shares of the new equity securities
                               issued with respect to one share of such Basket
                               Stock.



                                      A-12

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                               7. No adjustments to any Exchange Ratio shall be
                               required other than those specified above. The
                               adjustments specified above do not cover all of
                               the events that could affect the Market Price of
                               any Basket Stock. However, the Issuer may, at
                               its sole discretion, cause the Calculation Agent
                               to make additional changes to the Exchange Ratio
                               for any Basket Stock upon the occurrence of
                               corporate or other similar events that affect or
                               could potentially affect market prices of, or
                               shareholders' rights in, the Basket Stock (or
                               other Exchange Property) but only to reflect
                               such changes, and not with the aim of changing
                               relative investment risk.

                               No adjustments to any Exchange Ratio shall be
                               required unless such adjustment would require a
                               change of at least 0.1% in the Exchange Ratio
                               then in effect. The Exchange Ratio resulting
                               from any of the adjustments specified above
                               shall be rounded to the nearest one-millionth
                               with five ten-millionths being rounded upward.

                               If the holder of this Note exercises the
                               Exchange Right and the Issuer elects to deliver
                               the Basket Stocks (or Other Exchange Property),
                               the Issuer will continue to make such
                               adjustments until the close of business on the
                               day prior to the Exchange Settlement Date.

                               The Calculation Agent shall be solely
                               responsible for the determination and
                               calculation of any adjustments to the Exchange
                               Ratios and any related determinations and
                               calculations with respect to any distributions
                               of stock, other securities or other property or
                               assets (including cash) in connection with any
                               corporate event described in paragraph 5 or 6
                               above, and its determinations and calculations
                               with respect thereto shall be conclusive.

                               The Calculation Agent shall provide information
                               as to any adjustments to any Exchange Ratio upon
                               written request by the holder of this Note.

Market Disruption Event...     "Market Disruption Event" means, with respect to
                               any Basket Stock (and any other security that
                               may be included


                                      A-13

<PAGE>


                               as Exchange Property) the occurrence or
                               existence of any of the following events:

                                  (i) a suspension, absence or material
                                  limitation of trading of such Basket Stock on
                                  the primary market for such Basket Stock for
                                  more than two hours of trading or during the
                                  one-half hour period preceding the close of
                                  the principal trading session in such market;
                                  or a breakdown or failure in the price and
                                  trade reporting systems of the primary market
                                  for such Basket Stock as a result of which
                                  the reported trading prices for such Basket
                                  Stock during the last one-half hour preceding
                                  the close of the principal trading session in
                                  such market are materially inaccurate; or the
                                  suspension, absence or material limitation of
                                  trading on the primary market for trading in
                                  options contracts related to such Basket
                                  Stock, if available, during the one-half hour
                                  period preceding the close of the principal
                                  trading session in the applicable market, in
                                  each case as determined by the Calculation
                                  Agent in its sole discretion; and

                                  (ii) a determination by the Calculation Agent
                                  in its sole discretion that any event
                                  described in clause (i) above materially
                                  interfered with the ability of the Issuer or
                                  any of its affiliates to unwind or adjust all
                                  or a material portion of the hedge with
                                  respect to the 0.25% Exchangeable Notes due
                                  May 30, 2008 (Exchangeable for Shares of
                                  Common Stock of Six Software Companies).

                               For purposes of determining whether a Market
                               Disruption Event has occurred: (1) a limitation
                               on the hours or number of days of trading shall
                               not constitute a Market Disruption Event if it
                               results from an announced change in the regular
                               business hours of the relevant exchange, (2) a
                               decision to permanently discontinue trading in
                               the relevant options contract shall not
                               constitute a Market Disruption Event, (3)
                               limitations pursuant to NYSE Rule 80A (or any
                               applicable rule or regulation enacted or
                               promulgated by the NYSE, any other
                               self-regulatory organization or the Securities
                               and Exchange Commission of scope similar to NYSE
                               Rule 80A as determined by the Calculation Agent)
                               on trading during significant market
                               fluctuations shall constitute a suspension,
                               absence or


                                      A-14

<PAGE>


                               material limitation of trading, (4) a suspension
                               of trading in options contracts on any Basket
                               Stock by the primary securities market trading
                               in such options, if available, by reason of (x)
                               a price change exceeding limits set by such
                               securities exchange or market, (y) an imbalance
                               of orders relating to such contracts or (z) a
                               disparity in bid and ask quotes relating to such
                               contracts shall constitute a suspension, absence
                               or material limitation of trading in options
                               contracts related to such Basket Stock and (5) a
                               suspension, absence or material limitation of
                               trading on the primary securities market on
                               which options contracts related to any Basket
                               Stock are traded shall not include any time when
                               such securities market is itself closed for
                               trading under ordinary circumstances.

Alternate Exchange
Calculation in case of an
Event of Default..........     In case an Event of Default with respect to this
                               Note shall have occurred and be continuing, the
                               amount declared due and payable upon any
                               acceleration of this Note shall be determined by
                               MS & Co., as Calculation Agent, and shall be
                               equal to the principal amount of this Note plus
                               any accrued and unpaid interest at the Interest
                               Rate to but not including the date of
                               acceleration; provided that if (x) the holder of
                               this Note has submitted an Official Notice of
                               Exchange to the Issuer in accordance with the
                               Exchange Right or (y) the Issuer has called this
                               Note, other than a call for the cash Call Price,
                               in accordance with the MSDW Call Right, the
                               amount declared due and payable upon any such
                               acceleration shall be an amount in cash for each
                               $1,000 principal amount of this Note equal to
                               the Exchange Ratio times the Market Price,
                               determined by the Calculation Agent as of the
                               Exchange Date or as of the date of acceleration,
                               respectively, and shall not include any accrued
                               and unpaid interest thereon; provided further
                               that if the Issuer has called this Note for cash
                               in an amount equal to the Call Price, in
                               accordance with the MSDW Call Right, the amount
                               declared due and payable upon any such
                               acceleration shall be an amount in cash for each
                               $1,000 principal amount of this Note equal to
                               the Call Price.


                                      A-15

<PAGE>


     Morgan Stanley Dean Witter & Co., a Delaware corporation (together with
its successors and assigns, the "Issuer"), for value received, hereby promises
to pay to CEDE & Co., or registered assignees, the principal sum of
U.S.$13,000,000 (UNITED STATES DOLLARS THIRTEEN MILLION), on the Maturity Date
specified above (except to the extent redeemed or repaid prior to maturity) and
to pay interest thereon at the Interest Rate per annum specified above, from
and including the Interest Accrual Date specified above until the principal
hereof is paid or duly made available for payment weekly, monthly, quarterly,
semiannually or annually in arrears as specified above as the Interest Payment
Period on each Interest Payment Date (as specified above), commencing on the
Interest Payment Date next succeeding the Interest Accrual Date specified
above, and at maturity (or on any redemption or repayment date); provided,
however, that if the Interest Accrual Date occurs between a Record Date, as
defined below, and the next succeeding Interest Payment Date, interest payments
will commence on the second Interest Payment Date succeeding the Interest
Accrual Date to the registered holder of this Note on the Record Date with
respect to such second Interest Payment Date; and provided, further, that if
this Note is subject to "Annual Interest Payments," interest payments shall be
made annually in arrears and the term "Interest Payment Date" shall be deemed
to mean the first day of March in each year.

     Interest on this Note will accrue from and including the most recent date
to which interest has been paid or duly provided for, or, if no interest has
been paid or duly provided for, from and including the Interest Accrual Date,
until, but excluding the date the principal hereof has been paid or duly made
available for payment. The interest so payable, and punctually paid or duly
provided for, on any Interest Payment Date will, subject to certain exceptions
described herein, be paid to the person in whose name this Note (or one or more
predecessor Notes) is registered at the close of business on the date 15
calendar days prior to such Interest Payment Date (whether or not a Business
Day (as defined below)) (each such date, a "Record Date"); provided, however,
that interest payable at maturity (or any redemption or repayment date) will be
payable to the person to whom the principal hereof shall be payable. As used
herein, "Business Day" means any day, other than a Saturday or Sunday, (a) that
is neither a legal holiday nor a day on which banking institutions are
authorized or required by law or regulation to close (x) in The City of New
York or (y) if this Note is denominated in a Specified Currency other than U.S.
dollars, euro or Australian dollars, in the principal financial center of the
country of the Specified Currency, or (z) if this Note is denominated in
Australian dollars, in Sydney and (b) if this Note is denominated in euro, that
is also a day on which the Trans-European Automated Real-time Gross Settlement
Express Transfer System ("TARGET") is operating (a "TARGET Settlement Day").

     Payment of the principal of this Note, any premium and the interest due at
maturity (or any redemption or repayment date), unless this Note is denominated
in a Specified Currency other than U.S. dollars and is to be paid in whole or
in part in such Specified Currency, will be made in immediately available funds
upon surrender of this Note at the office or agency of the Paying Agent, as
defined on the reverse hereof, maintained for that purpose in the Borough of
Manhattan, The City of New York, or at such other paying agency as the Issuer
may determine, in U.S. dollars. U.S. dollar payments of interest, other than
interest due at maturity or on any date of redemption or repayment, will be
made by U.S. dollar check mailed to the address of the person entitled thereto
as such address shall appear in the Note register. A holder of U.S. $10,000,000
(or the equivalent in a Specified Currency) or more in aggregate principal
amount of Notes having the same Interest



                                      A-16

<PAGE>



Payment Date, the interest on which is payable in U.S. dollars, shall be
entitled to receive payments of interest, other than interest due at maturity
or on any date of redemption or repayment, by wire transfer of immediately
available funds if appropriate wire transfer instructions have been received by
the Paying Agent in writing not less than 15 calendar days prior to the
applicable Interest Payment Date.

     If this Note is denominated in a Specified Currency other than U.S.
dollars, and the holder does not elect (in whole or in part) to receive payment
in U.S. dollars pursuant to the next succeeding paragraph, payments of
interest, principal or any premium with regard to this Note will be made by
wire transfer of immediately available funds to an account maintained by the
holder hereof with a bank located outside the United States if appropriate wire
transfer instructions have been received by the Paying Agent in writing, with
respect to payments of interest, on or prior to the fifth Business Day after
the applicable Record Date and, with respect to payments of principal or any
premium, at least ten Business Days prior to the Maturity Date or any
redemption or repayment date, as the case may be; provided that, if payment of
interest, principal or any premium with regard to this Note is payable in euro,
the account must be a euro account in a country for which the euro is the
lawful currency, provided, further, that if such wire transfer instructions are
not received, such payments will be made by check payable in such Specified
Currency mailed to the address of the person entitled thereto as such address
shall appear in the Note register; and provided, further, that payment of the
principal of this Note, any premium and the interest due at maturity (or on any
redemption or repayment date) will be made upon surrender of this Note at the
office or agency referred to in the preceding paragraph.

     If so indicated on the face hereof, the holder of this Note, if
denominated in a Specified Currency other than U.S. dollars, may elect to
receive all or a portion of payments on this Note in U.S. dollars by
transmitting a written request to the Paying Agent, on or prior to the fifth
Business Day after such Record Date or at least ten Business Days prior to the
Maturity Date or any redemption or repayment date, as the case may be. Such
election shall remain in effect unless such request is revoked by written
notice to the Paying Agent as to all or a portion of payments on this Note at
least five Business Days prior to such Record Date, for payments of interest,
or at least ten days prior to the Maturity Date or any redemption or repayment
date, for payments of principal, as the case may be.

     If the holder elects to receive all or a portion of payments of principal
of and any premium and interest on this Note, if denominated in a Specified
Currency other than U.S. dollars, in U.S. dollars, the Exchange Rate Agent (as
defined on the reverse hereof) will convert such payments into U.S. dollars. In
the event of such an election, payment in respect of this Note will be based
upon the exchange rate as determined by the Exchange Rate Agent based on the
highest bid quotation in The City of New York received by such Exchange Rate
Agent at approximately 11:00 a.m., New York City time, on the second Business
Day preceding the applicable payment date from three recognized foreign
exchange dealers (one of which may be the Exchange Rate Agent unless such
Exchange Rate Agent is an affiliate of the Issuer) for the purchase by the
quoting dealer of U.S. dollars for the Specified Currency for settlement on
such payment date in the amount of the Specified Currency payable in the
absence of such an election to such holder and at which the applicable dealer
commits to execute a contract. If such bid quotations are not available, such
payment will be made in the



                                      A-17

<PAGE>



Specified Currency. All currency exchange costs will be borne by the holder of
this Note by deductions from such payments.

     Reference is hereby made to the further provisions of this Note set forth
on the reverse hereof, which further provisions shall for all purposes have the
same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee referred to on the reverse hereof by manual signature, this Note shall
not be entitled to any benefit under the Senior Indenture, as defined on the
reverse hereof, or be valid or obligatory for any purpose.





                                      A-18

<PAGE>



     IN WITNESS WHEREOF, the Issuer has caused this Note to be duly executed.


DATED: May 30, 2001                      MORGAN STANLEY DEAN WITTER & CO.



                                         By:
                                            ------------------------------------
                                            Name:  Alexander C. Frank
                                            Title: Treasurer

TRUSTEE'S CERTIFICATE
      OF AUTHENTICATION

This  is one of the Notes referred
   to in the within-mentioned
   Senior Indenture.

THE CHASE MANHATTAN BANK,
   as Trustee



By:
   -------------------------------
        Authorized Officer




                                       19

<PAGE>



                              REVERSE OF SECURITY

     This Note is one of a duly authorized issue of Senior Global Medium-Term
Notes, Series C, having maturities more than nine months from the date of issue
(the "Notes") of the Issuer. The Notes are issuable under an Amended and
Restated Senior Indenture, dated as of May 1, 1999, between the Issuer and The
Chase Manhattan Bank, as Trustee (the "Trustee," which term includes any
successor trustee under the Senior Indenture) (as may be amended or
supplemented from time to time, the "Senior Indenture"), to which Senior
Indenture and all indentures supplemental thereto reference is hereby made for
a statement of the respective rights, limitations of rights, duties and
immunities of the Issuer, the Trustee and holders of the Notes and the terms
upon which the Notes are, and are to be, authenticated and delivered. The
Issuer has appointed The Chase Manhattan Bank at its corporate trust office in
The City of New York as the paying agent (the "Paying Agent," which term
includes any additional or successor Paying Agent appointed by the Issuer) with
respect to the Notes. The terms of individual Notes may vary with respect to
interest rates, interest rate formulas, issue dates, maturity dates, or
otherwise, all as provided in the Senior Indenture. To the extent not
inconsistent herewith, the terms of the Senior Indenture are hereby
incorporated by reference herein.

     Unless otherwise indicated on the face hereof, this Note will not be
subject to any sinking fund and, unless otherwise provided on the face hereof
in accordance with the provisions of the following two paragraphs, will not be
redeemable or subject to repayment at the option of the holder prior to
maturity.

     If so indicated on the face hereof, this Note may be redeemed in whole or
in part at the option of the Issuer on or after the Initial Redemption Date
specified on the face hereof on the terms set forth on the face hereof,
together with interest accrued and unpaid hereon to the date of redemption. If
this Note is subject to "Annual Redemption Percentage Reduction," the Initial
Redemption Percentage indicated on the face hereof will be reduced on each
anniversary of the Initial Redemption Date by the Annual Redemption Percentage
Reduction specified on the face hereof until the redemption price of this Note
is 100% of the principal amount hereof, together with interest accrued and
unpaid hereon to the date of redemption. Notice of redemption shall be mailed
to the registered holders of the Notes designated for redemption at their
addresses as the same shall appear on the Note register not less than 30 nor
more than 60 days prior to the date fixed for redemption or within the
Redemption Notice Period specified on the face hereof, subject to all the
conditions and provisions of the Senior Indenture. In the event of redemption
of this Note in part only, a new Note or Notes for the amount of the unredeemed
portion hereof shall be issued in the name of the holder hereof upon the
cancellation hereof.

     If so indicated on the face of this Note, this Note will be subject to
repayment at the option of the holder on the Optional Repayment Date or Dates
specified on the face hereof on the terms set forth herein. On any Optional
Repayment Date, this Note will be repayable in whole or in part in increments
of $1,000 or, if this Note is denominated in a Specified Currency other than
U.S. dollars, in increments of 1,000 units of such Specified Currency (provided
that any remaining principal amount hereof shall not be less than the minimum
authorized denomination hereof) at the option of the holder hereof at a price
equal to 100% of the principal amount to be repaid,


                                       20

<PAGE>


together with interest accrued and unpaid hereon to the date of repayment. For
this Note to be repaid at the option of the holder hereof, the Paying Agent
must receive at its corporate trust office in the Borough of Manhattan, The
City of New York, at least 15 but not more than 30 days prior to the date of
repayment, (i) this Note with the form entitled "Option to Elect Repayment"
below duly completed or (ii) a telegram, telex, facsimile transmission or a
letter from a member of a national securities exchange or the National
Association of Securities Dealers, Inc. or a commercial bank or a trust company
in the United States setting forth the name of the holder of this Note, the
principal amount hereof, the certificate number of this Note or a description
of this Note's tenor and terms, the principal amount hereof to be repaid, a
statement that the option to elect repayment is being exercised thereby and a
guarantee that this Note, together with the form entitled "Option to Elect
Repayment" duly completed, will be received by the Paying Agent not later than
the fifth Business Day after the date of such telegram, telex, facsimile
transmission or letter; provided, that such telegram, telex, facsimile
transmission or letter shall only be effective if this Note and form duly
completed are received by the Paying Agent by such fifth Business Day. Exercise
of such repayment option by the holder hereof shall be irrevocable. In the
event of repayment of this Note in part only, a new Note or Notes for the
amount of the unpaid portion hereof shall be issued in the name of the holder
hereof upon the cancellation hereof.

     Interest payments on this Note will include interest accrued to but
excluding the Interest Payment Dates or the Maturity Date (or any earlier
redemption or repayment date), as the case may be. Unless otherwise provided on
the face hereof, interest payments for this Note will be computed and paid on
the basis of a 360-day year of twelve 30-day months.

     In the case where the Interest Payment Date or the Maturity Date (or any
redemption or repayment date) does not fall on a Business Day, payment of
interest, premium, if any, or principal otherwise payable on such date need not
be made on such date, but may be made on the next succeeding Business Day with
the same force and effect as if made on the Interest Payment Date or on the
Maturity Date (or any redemption or repayment date), and no interest on such
payment shall accrue for the period from and after the Interest Payment Date or
the Maturity Date (or any redemption or repayment date) to such next succeeding
Business Day.

     This Note and all the obligations of the Issuer hereunder are direct,
unsecured obligations of the Issuer and rank without preference or priority
among themselves and pari passu with all other existing and future unsecured
and unsubordinated indebtedness of the Issuer, subject to certain statutory
exceptions in the event of liquidation upon insolvency.

     This Note, and any Note or Notes issued upon transfer or exchange hereof,
is issuable only in fully registered form, without coupons, and, if denominated
in U.S. dollars, unless otherwise stated above, is issuable only in
denominations of U.S. $1,000 and any integral multiple of U.S. $1,000 in excess
thereof. If this Note is denominated in a Specified Currency other than U.S.
dollars, then, unless a higher minimum denomination is required by applicable
law, it is issuable only in denominations of the equivalent of U.S. $1,000
(rounded to an integral multiple of 1,000 units of such Specified Currency), or
any amount in excess thereof which is an integral multiple of 1,000 units of
such Specified Currency, as determined by reference to the noon dollar buying
rate in The City of New York for cable transfers of such Specified Currency
published by the


                                       21

<PAGE>


Federal Reserve Bank of New York (the "Market Exchange Rate") on the Business
Day immediately preceding the date of issuance.

     The Trustee has been appointed registrar for the Notes, and the Trustee
will maintain at its office in The City of New York a register for the
registration and transfer of Notes. This Note may be transferred at the
aforesaid office of the Trustee by surrendering this Note for cancellation,
accompanied by a written instrument of transfer in form satisfactory to the
Trustee and duly executed by the registered holder hereof in person or by the
holder's attorney duly authorized in writing, and thereupon the Trustee shall
issue in the name of the transferee or transferees, in exchange herefor, a new
Note or Notes having identical terms and provisions and having a like aggregate
principal amount in authorized denominations, subject to the terms and
conditions set forth herein; provided, however, that the Trustee will not be
required (i) to register the transfer of or exchange any Note that has been
called for redemption in whole or in part, except the unredeemed portion of
Notes being redeemed in part, (ii) to register the transfer of or exchange any
Note if the holder thereof has exercised his right, if any, to require the
Issuer to repurchase such Note in whole or in part, except the portion of such
Note not required to be repurchased, or (iii) to register the transfer of or
exchange Notes to the extent and during the period so provided in the Senior
Indenture with respect to the redemption of Notes. Notes are exchangeable at
said office for other Notes of other authorized denominations of equal
aggregate principal amount having identical terms and provisions. All such
exchanges and transfers of Notes will be free of charge, but the Issuer may
require payment of a sum sufficient to cover any tax or other governmental
charge in connection therewith. All Notes surrendered for exchange shall be
accompanied by a written instrument of transfer in form satisfactory to the
Trustee and executed by the registered holder in person or by the holder's
attorney duly authorized in writing. The date of registration of any Note
delivered upon any exchange or transfer of Notes shall be such that no gain or
loss of interest results from such exchange or transfer.

     In case this Note shall at any time become mutilated, defaced or be
destroyed, lost or stolen and this Note or evidence of the loss, theft or
destruction thereof (together with the indemnity hereinafter referred to and
such other documents or proof as may be required in the premises) shall be
delivered to the Trustee, the Issuer in its discretion may execute a new Note
of like tenor in exchange for this Note, but, if this Note is destroyed, lost
or stolen, only upon receipt of evidence satisfactory to the Trustee and the
Issuer that this Note was destroyed or lost or stolen and, if required, upon
receipt also of indemnity satisfactory to each of them. All expenses and
reasonable charges associated with procuring such indemnity and with the
preparation, authentication and delivery of a new Note shall be borne by the
owner of the Note mutilated, defaced, destroyed, lost or stolen.

     The Senior Indenture provides that (a) if an Event of Default (as defined
in the Senior Indenture) due to the default in payment of principal of,
premium, if any, or interest on, any series of debt securities issued under the
Senior Indenture, including the series of Senior Medium-Term Notes of which
this Note forms a part, or due to the default in the performance or breach of
any other covenant or warranty of the Issuer applicable to the debt securities
of such series but not applicable to all outstanding debt securities issued
under the Senior Indenture shall have occurred and be continuing, either the
Trustee or the holders of not less than 25% in


                                       22

<PAGE>


principal amount of the debt securities of each affected series (voting as a
single class) may then declare the principal of all debt securities of all such
series and interest accrued thereon to be due and payable immediately and (b)
if an Event of Default due to a default in the performance of any other of the
covenants or agreements in the Senior Indenture applicable to all outstanding
debt securities issued thereunder, including this Note, or due to certain
events of bankruptcy or insolvency of the Issuer, shall have occurred and be
continuing, either the Trustee or the holders of not less than 25% in principal
amount of all debt securities issued under the Senior Indenture then
outstanding (treated as one class) may declare the principal of all such debt
securities and interest accrued thereon to be due and payable immediately, but
upon certain conditions such declarations may be annulled and past defaults may
be waived (except a continuing default in payment of principal (or premium, if
any) or interest on such debt securities) by the holders of a majority in
principal amount of the debt securities of all affected series then
outstanding.

     If the face hereof indicates that this Note is subject to "Modified
Payment upon Acceleration," then (i) if the principal hereof is declared to be
due and payable as described in the preceding paragraph, the amount of
principal due and payable with respect to this Note shall be limited to the
aggregate principal amount hereof multiplied by the sum of the Issue Price
specified on the face hereof (expressed as a percentage of the aggregate
principal amount) plus the original issue discount amortized from the Interest
Accrual Date to the date of declaration, which amortization shall be calculated
using the "interest method" (computed in accordance with generally accepted
accounting principles in effect on the date of declaration), (ii) for the
purpose of any vote of securityholders taken pursuant to the Senior Indenture
prior to the acceleration of payment of this Note, the principal amount hereof
shall equal the amount that would be due and payable hereon, calculated as set
forth in clause (i) above, if this Note were declared to be due and payable on
the date of any such vote and (iii) for the purpose of any vote of
securityholders taken pursuant to the Senior Indenture following the
acceleration of payment of this Note, the principal amount hereof shall equal
the amount of principal due and payable with respect to this Note, calculated
as set forth in clause (i) above.

     If the face hereof indicates that this Note is subject to "Tax Redemption
and Payment of Additional Amounts," this Note may be redeemed, as a whole, at
the option of the Issuer at any time prior to maturity, upon the giving of a
notice of redemption as described below, at a redemption price equal to 100% of
the principal amount hereof, together with accrued interest to the date fixed
for redemption (except that if this Note is subject to "Modified Payment upon
Acceleration or Redemption," such redemption price would be limited to the
aggregate principal amount hereof multiplied by the sum of the Issue Price
specified on the face hereof (expressed as a percentage of the aggregate
principal amount) plus the original issue discount amortized from the Interest
Accrual Date to the date of redemption, which amortization shall be calculated
using the "interest method" (computed in accordance with generally accepted
accounting principles in effect on the date of redemption) (the "Amortized
Amount")), if the Issuer determines that, as a result of any change in or
amendment to the laws (or any regulations or rulings promulgated thereunder) of
the United States or of any political subdivision or taxing authority thereof
or therein affecting taxation, or any change in official position regarding the
application or interpretation of such laws, regulations or rulings, which
change or amendment becomes effective on or after the Initial Offering Date
hereof, the Issuer has or will become obligated to


                                                        23

<PAGE>


pay Additional Amounts (as defined below) with respect to this Note as
described below. Prior to the giving of any Notice of redemption pursuant to
this paragraph, the Issuer shall deliver to the Trustee (i) a certificate
stating that the Issuer is entitled to effect such redemption and setting forth
a statement of facts showing that the conditions precedent to the right of the
Issuer to so redeem have occurred, and (ii) an opinion of independent counsel
satisfactory to the Trustee to such effect based on such statement of facts;
provided that no such notice of redemption shall be given earlier than 60 days
prior to the earliest date on which the Issuer would be obligated to pay such
Additional Amounts if a payment in respect of this Note were then due.

     Notice of redemption will be given not less than 30 nor more than 60 days
prior to the date fixed for redemption or within the Redemption Notice Period
specified on face hereof, which date and the applicable redemption price will
be specified in the Notice.

     If the face hereof indicates that this Note is subject to "Tax Redemption
and Payment of Additional Amounts," the Issuer will, subject to certain
exceptions and limitations set forth below, pay such additional amounts (the
"Additional Amounts") to the holder of this Note who is a United States Alien
as may be necessary in order that every net payment of the principal of and
interest on this Note and any other amounts payable on this Note, after
withholding for or on account of any present or future tax, assessment or
governmental charge imposed upon or as a result of such payment by the United
States (or any political subdivision or taxing authority thereof or therein),
will not be less than the amount provided for in this Note to be then due and
payable. The Issuer will not, however, be required to make any payment of
Additional Amounts to any such holder for or on account of:

          (a) any such tax, assessment or other governmental charge that would
     not have been so imposed but for (i) the existence of any present or
     former connection between such holder (or between a fiduciary, settlor,
     beneficiary, member or shareholder of such holder, if such holder is an
     estate, a trust, a partnership or a corporation) and the United States and
     its possessions, including, without limitation, such holder (or such
     fiduciary, settlor, beneficiary, member or shareholder) being or having
     been a citizen or resident thereof or being or having been engaged in a
     trade or business or present therein or having, or having had, a permanent
     establishment therein or (ii) the presentation by the holder of this Note
     for payment on a date more than 15 days after the date on which such
     payment became due and payable or the date on which payment thereof is
     duly provided for, whichever occurs later;

          (b) any estate, inheritance, gift, sales, transfer or personal
     property tax or any similar tax, assessment or governmental charge;

          (c) any tax, assessment or other governmental charge imposed by
     reason of such holder's past or present status as a personal holding
     company or foreign personal holding company or controlled foreign
     corporation or passive foreign investment company with respect to the
     United States or as a corporation which accumulates earnings to avoid
     United States federal income tax or as a private foundation or other
     tax-exempt organization;


                                       24

<PAGE>


          (d) any tax, assessment or other governmental charge that is payable
     otherwise than by withholding from payments on or in respect of this Note;

          (e) any tax, assessment or other governmental charge required to be
     withheld by any Paying Agent from any payment of principal of, or interest
     on, this Note, if such payment can be made without such withholding by any
     other Paying Agent in a city in Western Europe;

          (f) any tax, assessment or other governmental charge that would not
     have been imposed but for the failure to comply with certification,
     information or other reporting requirements concerning the nationality,
     residence or identity of the holder or beneficial owner of this Note, if
     such compliance is required by statute or by regulation of the United
     States or of any political subdivision or taxing authority thereof or
     therein as a precondition to relief or exemption from such tax, assessment
     or other governmental charge;

          (g) any tax, assessment or other governmental charge imposed by
     reason of such holder's past or present status as the actual or
     constructive owner of 10% or more of the total combined voting power of
     all classes of stock entitled to vote of the Issuer or as a direct or
     indirect subsidiary of the Issuer; or

          (h) any combination of items (a), (b), (c), (d), (e), (f) or (g);

nor shall Additional Amounts be paid with respect to any payment on this Note
to a United States Alien who is a fiduciary or partnership or other than the
sole beneficial owner of such payment to the extent such payment would be
required by the laws of the United States (or any political subdivision
thereof) to be included in the income, for tax purposes, of a beneficiary or
settlor with respect to such fiduciary or a member of such partnership or a
beneficial owner who would not have been entitled to the Additional Amounts had
such beneficiary, settlor, member or beneficial owner been the holder of this
Note.

     The Senior Indenture permits the Issuer and the Trustee, with the consent
of the holders of not less than a majority in aggregate principal amount of the
debt securities of all series issued under the Senior Indenture then
outstanding and affected (voting as one class), to execute supplemental
indentures adding any provisions to or changing in any manner the rights of the
holders of each series so affected; provided that the Issuer and the Trustee
may not, without the consent of the holder of each outstanding debt security
affected thereby, (a) extend the final maturity of any such debt security, or
reduce the principal amount thereof, or reduce the rate or extend the time of
payment of interest thereon, or reduce any amount payable on redemption or
repayment thereof, or change the currency of payment thereof, or modify or
amend the provisions for conversion of any currency into any other currency, or
modify or amend the provisions for conversion or exchange of the debt security
for securities of the Issuer or other entities (other than as provided in the
antidilution provisions or other similar adjustment provisions of the debt
securities or otherwise in accordance with the terms thereof), or impair or
affect the rights of any holder to institute suit for the payment thereof
without the consent of the holder of each debt security so affected or (b)
reduce the aforesaid percentage in principal amount of debt securities the
consent of the holders of which is required for any such supplemental
indenture.


                                       25

<PAGE>


     Except as set forth below, if the principal of, premium, if any, or
interest on, this Note is payable in a Specified Currency other than U.S.
dollars and such Specified Currency is not available to the Issuer for making
payments hereon due to the imposition of exchange controls or other
circumstances beyond the control of the Issuer or is no longer used by the
government of the country issuing such currency or for the settlement of
transactions by public institutions within the international banking community,
then the Issuer will be entitled to satisfy its obligations to the holder of
this Note by making such payments in U.S. dollars on the basis of the Market
Exchange Rate on the date of such payment or, if the Market Exchange Rate is
not available on such date, as of the most recent practicable date; provided,
however, that if the euro has been substituted for such Specified Currency, the
Issuer may at its option (or shall, if so required by applicable law) without
the consent of the holder of this Note effect the payment of principal of,
premium, if any, or interest on, any Note denominated in such Specified
Currency in euro in lieu of such Specified Currency in conformity with legally
applicable measures taken pursuant to, or by virtue of, the treaty establishing
the European Community (the "EC"), as amended by the treaty on European Union
(as so amended, the "Treaty"). Any payment made under such circumstances in
U.S. dollars or euro where the required payment is in an unavailable Specified
Currency will not constitute an Event of Default. If such Market Exchange Rate
is not then available to the Issuer or is not published for a particular
Specified Currency, the Market Exchange Rate will be based on the highest bid
quotation in The City of New York received by the Exchange Rate Agent at
approximately 11:00 a.m., New York City time, on the second Business Day
preceding the date of such payment from three recognized foreign exchange
dealers (the "Exchange Dealers") for the purchase by the quoting Exchange
Dealer of the Specified Currency for U.S. dollars for settlement on the payment
date, in the aggregate amount of the Specified Currency payable to those
holders or beneficial owners of Notes and at which the applicable Exchange
Dealer commits to execute a contract. One of the Exchange Dealers providing
quotations may be the Exchange Rate Agent unless the Exchange Rate Agent is an
affiliate of the Issuer. If those bid quotations are not available, the
Exchange Rate Agent shall determine the market exchange rate at its sole
discretion.

     The "Exchange Rate Agent" shall be Morgan Stanley & Co. Incorporated,
unless otherwise indicated on the face hereof.

     All determinations referred to above made by, or on behalf of, the Issuer
or by, or on behalf of, the Exchange Rate Agent shall be at such entity's sole
discretion and shall, in the absence of manifest error, be conclusive for all
purposes and binding on holders of Notes and coupons.

     So long as this Note shall be outstanding, the Issuer will cause to be
maintained an office or agency for the payment of the principal of and premium,
if any, and interest on this Note as herein provided in the Borough of
Manhattan, The City of New York, and an office or agency in said Borough of
Manhattan for the registration, transfer and exchange as aforesaid of the
Notes. The Issuer may designate other agencies for the payment of said
principal, premium and interest at such place or places (subject to applicable
laws and regulations) as the Issuer may decide. So long as there shall be such
an agency, the Issuer shall keep the Trustee advised of the names and locations
of such agencies, if any are so designated.


                                       26

<PAGE>


     With respect to moneys paid by the Issuer and held by the Trustee or any
Paying Agent for payment of the principal of or interest or premium, if any, on
any Notes that remain unclaimed at the end of two years after such principal,
interest or premium shall have become due and payable (whether at maturity or
upon call for redemption or otherwise), (i) the Trustee or such Paying Agent
shall notify the holders of such Notes that such moneys shall be repaid to the
Issuer and any person claiming such moneys shall thereafter look only to the
Issuer for payment thereof and (ii) such moneys shall be so repaid to the
Issuer. Upon such repayment all liability of the Trustee or such Paying Agent
with respect to such moneys shall thereupon cease, without, however, limiting
in any way any obligation that the Issuer may have to pay the principal of or
interest or premium, if any, on this Note as the same shall become due.

     No provision of this Note or of the Senior Indenture shall alter or impair
the obligation of the Issuer, which is absolute and unconditional, to pay the
principal of, premium, if any, and interest on this Note at the time, place,
and rate, and in the coin or currency, herein prescribed unless otherwise
agreed between the Issuer and the registered holder of this Note.

     Prior to due presentment of this Note for registration of transfer, the
Issuer, the Trustee and any agent of the Issuer or the Trustee may treat the
holder in whose name this Note is registered as the owner hereof for all
purposes, whether or not this Note be overdue, and none of the Issuer, the
Trustee or any such agent shall be affected by notice to the contrary.

     No recourse shall be had for the payment of the principal of, premium, if
any, or the interest on this Note, for any claim based hereon, or otherwise in
respect hereof, or based on or in respect of the Senior Indenture or any
indenture supplemental thereto, against any incorporator, shareholder, officer
or director, as such, past, present or future, of the Issuer or of any
successor corporation, either directly or through the Issuer or any successor
corporation, whether by virtue of any constitution, statute or rule of law or
by the enforcement of any assessment or penalty or otherwise, all such
liability being, by the acceptance hereof and as part of the consideration for
the issue hereof, expressly waived and released.

     This Note shall for all purposes be governed by, and construed in
accordance with, the laws of the State of New York.

     As used herein, the term "United States Alien" means any person who, for
United States federal income tax purposes, is a foreign corporation, a
non-resident alien individual, a non- resident alien fiduciary of a foreign
estate or trust, or a foreign partnership one or more of the members of which
is a foreign corporation, a non-resident alien individual or a non-resident
alien fiduciary of a foreign estate or trust.

     All terms used in this Note which are defined in the Senior Indenture and
not otherwise defined herein shall have the meanings assigned to them in the
Senior Indenture.


                                       27

<PAGE>


                                 ABBREVIATIONS

     The following abbreviations, when used in the inscription on the face of
this instrument, shall be construed as though they were written out in full
according to applicable laws or regulations:



     TEN COM - as tenants in common
     TEN ENT - as tenants by the entireties
     JT TEN  - as joint tenants with right of survivorship and not as tenants in
               common


   UNIF GIFT MIN ACT - ________________________ Custodian_______________________
                                (Minor)                        (Cust)

   Under Uniform Gifts to Minors Act _____________________________________
                                                      (State)

     Additional abbreviations may also be used though not in the above list.


                            -----------------------




                                       28

<PAGE>



     FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and
transfer(s) unto


---------------------------------------
[PLEASE INSERT SOCIAL SECURITY OR OTHER
     IDENTIFYING NUMBER OF ASSIGNEE]


--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
[PLEASE PRINT OR TYPE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE]

the within Note and all rights thereunder, hereby irrevocably constituting and
appointing such person attorney to transfer such note on the books of the
Issuer, with full power of substitution in the premises.



Dated:________________________________


NOTICE: The signature to this assignment must correspond with the name as
        written upon the face of the within Note in every particular without
        alteration or enlargement or any change whatsoever.




                                       29

<PAGE>



                           OPTION TO ELECT REPAYMENT

     The undersigned hereby irrevocably requests and instructs the Issuer to
repay the within Note (or portion thereof specified below) pursuant to its
terms at a price equal to the principal amount thereof, together with interest
to the Optional Repayment Date, to the undersigned at


--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
        (Please print or typewrite name and address of the undersigned)


     If less than the entire principal amount of the within Note is to be
repaid, specify the portion thereof which the holder elects to have repaid:
________________________ ; and specify the denomination or denominations (which
shall not be less than the minimum authorized denomination) of the Notes to be
issued to the holder for the portion of the within Note not being repaid (in
the absence of any such specification, one such Note will be issued for the
portion not being repaid):____________________
   .


Dated:
     --------------------------    ---------------------------------------------
                                   NOTICE: The signature on this Option to
                                   Elect Repayment must correspond with the
                                   name as written upon the face of the within
                                   instrument in every particular without
                                   alteration or enlargement.




                                       30

<PAGE>


                                                                         ANNEX A


                          OFFICIAL NOTICE OF EXCHANGE


                                              Dated: [On or after June 30, 2001]

Morgan Stanley Dean Witter & Co.
1585 Broadway
New York, New York 10036

Morgan Stanley & Co. Incorporated, as
  Calculation Agent
1585 Broadway
New York, New York 10036
Fax No.: (212) 761-0674
(Attn: Meghan Maloney)


Dear Sirs:

     The undersigned holder of the Medium Term Notes, Series C, Senior Fixed
Rate Notes, 0.25% Exchangeable Notes due May 30, 2008 (Exchangeable for Shares
of Common Stock of Six Software Companies (the "Basket Stocks")) of Morgan
Stanley Dean Witter & Co. (CUSIP No. 617446GQ6) (the "Notes"), hereby
irrevocably elects to exercise with respect to the principal amount of the
Notes indicated below, as of the date hereof (or, if this letter is received
after 11:00 a.m. on any Trading Day, as of the next Trading Day), provided that
such day is prior the earliest of (i) the fifth scheduled Trading Day prior to
May 30, 2008, (ii) the fifth scheduled Trading Day prior to the Call Date and
(iii) in the event of a call for the cash Call Price, the last scheduled
Trading Day prior to the MSDW Notice Date, the Exchange Right as described in
Pricing Supplement No. 32 dated May 24, 2001 (the "Pricing Supplement") to the
Prospectus Supplement dated January 24, 2001 and the Prospectus dated January
24, 2001 related to Registration Statement No. 333- 47576. Terms not defined
herein have the meanings given to such terms in the Pricing Supplement. Please
date and acknowledge receipt of this notice in the place provided below on the
date of receipt, and fax a copy to the fax number indicated, whereupon MSDW
will deliver, at its sole option, shares of the Basket Stocks or cash 3
business days after the Exchange Date in accordance with the terms of the
Notes, as described in the Pricing Supplement.

     The undersigned certifies to you that (i) it is, or is duly authorized to
act for, the beneficial owner of the principal amount of the Notes indicated
below its signature (and attaches evidence of such ownership as provided by the
undersigned's position services department or the position services department
of the entity through which the undersigned holds its Notes) and (ii) it will
cause the principal amount of Notes to be exchanged to be transferred to the
Trustee on the Exchange Settlement Date.

     If the Exchange Settlement Date for this exchange falls after a Record
Date and prior to the succeeding Interest Payment Date, the undersigned will
deliver to the Trustee on the Exchange Settlement Date an amount of cash equal
to the interest payable on the succeeding Interest Payment Date with respect to
the principal amount of Notes to be exchanged. The amount of any such cash
payment will be determined by the Calculation Agent and indicated in its
acknowledgment of this Official Notice of Exchange.


                                     Very truly yours,


                                     -------------------------------------------
                                     [Name of Holder]


                                     By:
                                        ----------------------------------------
                                       [Title]


                                     -------------------------------------------
                                     [Fax No.]

                                     $
                                     -------------------------------------------
                                     Principal Amount of Notes to be surrendered
                                     for exchange



Receipt of the above Official
Notice of Exchange is hereby acknowledged
MORGAN STANLEY DEAN WITTER & CO., as Issuer
MORGAN STANLEY & CO. INCORPORATED, as Calculation Agent
By MORGAN STANLEY & CO. INCORPORATED, as Calculation Agent

By:
  -----------------------------

Title:
     --------------------------


Date and time of acknowledgment
                               ------------------------------------

Accrued interest, if any, due upon surrender of the Notes for exchange:
$_____________