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                                                                     EXHIBIT 4.1

                                  DISCOVER BANK

                      Master Servicer, Servicer and Seller

                                       and

                         U.S. BANK NATIONAL ASSOCIATION

                                     Trustee

                       on behalf of the Certificateholders



                             FIRST AMENDMENT TO THE
                       SERIES SUPPLEMENT FOR SERIES 2001-1
                           dated as of January 4, 2001

                                       to

                         POOLING AND SERVICING AGREEMENT
                           Dated as of October 1, 1993





                                   Dated as of
                                 August 24, 2001

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          THIS FIRST AMENDMENT TO THE SERIES SUPPLEMENT FOR SERIES 2001-1 (the
"Amendment"), dated as of August 24, 2001, is entered into by and between
DISCOVER BANK (formerly Greenwood Trust Company), a Delaware banking
corporation, as Master Servicer, Servicer and Seller ("Discover Bank") and U.S.
BANK NATIONAL ASSOCIATION (formerly First Bank National Association, successor
trustee to Bank of America Illinois, formerly Continental Bank, National
Association), as Trustee (the "Trustee").

          WHEREAS, Discover Bank and the Trustee have entered into the SERIES
SUPPLEMENT FOR SERIES 2001-1 (the "Series Supplement"), dated as of January 4,
2001 with respect to the Series 2001-1 Certificates, pursuant to Section 6.06 of
that certain Pooling and Servicing Agreement (the "Pooling and Servicing
Agreement"), dated as of October 1, 1993, as amended, relating to Discover Card
Master Trust I; and

          WHEREAS, pursuant to subsection 13.01(a)(4) of the Pooling and
Servicing Agreement, Discover Bank and the Trustee desire to amend the
definition of "Maximum Class B Credit Enhancement Amount" in the Series Term
Sheet.

          NOW, THEREFORE, in consideration of the foregoing and the mutual
agreements herein contained, each party agrees as follows for the benefit of the
other parties and for the benefit of the Certificateholders:

          1. Definitions. Unless otherwise specified, capitalized terms used in
this Amendment shall have the same meanings ascribed to them in the Series
Supplement.

          2. Amendment to the definition of "Maximum Class B Credit Enhancement
             Amount".

             (a)  The definition for "Maximum Class B Credit Enhancement Amount"
                  is hereby amended and restated in its entirety to read as
                  follows:

             On any Distribution Date (a) prior to the making of an Effective
             Alternative Credit Support Election, the greater of (i) $12,631,580
             and (ii) (x) if a Supplemental Credit Enhancement Event has not
             occurred, an amount equal to 7.5% of the Series Investor Interest
             as of the last day of the related Due Period, or (y) if a
             Supplemental Credit Enhancement Event has occurred, an amount equal
             to 8.0% of the Series Investor Interest as of the last day of the
             related Due Period, (b) subsequent to the making of an Effective
             Alternative Credit Support Election, the greater of (i) $12,631,580
             and (ii) an amount equal to 12.5% of the Series Investor Interest
             as of the last day of the related Due Period, provided, however,
             that if an Amortization Event with respect to the Series
             established hereby occurs, the Maximum Class B Credit Enhancement
             Amount for each Distribution Date thereafter shall equal the
             Maximum Class B Credit



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             Enhancement Amount for the Distribution Date immediately
             preceding the occurrence of the Amortization Event; and provided,
             further, that if a Credit Enhancement Drawing has been made,
             until such time as the Available Class B Credit Enhancement
             Amount has been reinstated in an amount at least equal to the
             amount of such Credit Enhancement Drawing, the Maximum Class B
             Credit Enhancement Amount shall be the Maximum Class B Credit
             Enhancement Amount as of the date of such Credit Enhancement
             Drawing.

          3. Effect Upon the Series Supplement. Except as specifically set forth
herein, the Series Supplement shall remain in full force and effect and is
hereby ratified and confirmed.

          4. Counterparts. This Amendment may be executed in two or more
counterparts (and by different parties on separate counterparts), each of which
shall be an original, but all of which together shall constitute one and the
same instrument.








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          IN WITNESS WHEREOF, Discover Bank and the Trustee have caused this
Amendment to be duly executed by their respective officers as of the day and
year first above written.

                                   DISCOVER BANK,
                                    as Master Servicer, Servicer and Seller



                                   By:     /s/ MICHAEL F. RICKERT
                                          --------------------------------------
                                   Name:   Michael F. Rickert
                                   Title:  Vice President, Chief Accounting
                                            Officer and Treasurer



                                   U.S. BANK NATIONAL ASSOCIATION, as Trustee



                                   By:     /s/ PATRICIA M. CHILD
                                          --------------------------------------
                                   Name:   Patricia M. Child
                                   Title:  Vice President





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