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                                                                 EXHIBIT 10.21


                                                                 EXECUTION COPY


            AMENDMENT NO. 1 TO AMENDED AND RESTATED CREDIT AGREEMENT

        THIS AMENDMENT NO. 1 ("Amendment No. 1") is made as of the 8th day of
May, 1997 by and among MEMBERWORKS INCORPORATED (formerly known as CardMember
Publishing Corporation), a Delaware corporation (the "Company"), the lenders
signatory hereto (the "Lenders") and BROWN BROTHERS HARRIMAN & CO., as agent
(in such capacity, the "Agent") for the Lenders.

                              W I T N E S S E T H:

        WHEREAS, the parties hereto have entered into an Amended and Restated
Credit Agreement dated as of April 8, 1996 (the "Credit Agreement"); and

        WHEREAS, the parties desire to amend the Credit Agreement as
hereinafter set forth;

        NOW, THEREFORE, the parties hereby agree as follows:

        SECTION 1. DEFINITIONS. Except as otherwise defined herein, capitalized
terms used herein have the meanings provided in the Credit Agreement.

        SECTION 2. AMENDMENT. Subject to the satisfaction of the conditions
precedent specified below, but effective as of the date hereof, the Credit
Agreement shall be amended as follows:

                (a) All references in the Credit Agreement to "CardMember
Publishing Corporation" shall mean "MemberWorks Incorporated."

                (b) Section 1.1 of the Credit Agreement shall be amended as
follows:

                        (1) The following definition shall be added after the
definition of "Closing Date": "'CMC' shall mean CardMember Marketing
Corporation, a Delaware corporation."

                        (2) The following definition shall be added after the
definition of "control": "'CPC' shall mean CardMember Publishing Corporation, a
Delaware corporation."

                        (3) The following definition shall be added after the
definition of "CPC": "'CSC' shall mean CardMember Services Corporation, a
Delaware corporation."

                        (4) The definition of "Maximum Amount" shall be amended
by deleting the reference therein to "$3,000,000" and replacing it with
"$7,000,000."

 
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                        (5) The definition of "Related Documents" shall be
amended by deleting the reference therein to ", the Shareholder Guaranty, the
Shareholder Pledge Agreement."

                        (6) The definitions of "Shareholder Guarantee" and
"Shareholder Pledge Agreement" are hereby deleted in their entirety.

                        (7) The following definition shall be added after the
definition of "Subsidiary Security Agreement": "'Travel Too' shall mean Travel
Too Ltd., a Delaware corporation."

                (c) Section 2.6 of the Credit Agreement shall be amended by
deleting the words "plus the applicable margin" in the first sentence thereof
and by deleting the second sentence thereof in its entirety.

                (d) Section 3.1(b) of the Credit Agreement shall be amended by
deleting the reference therein to "1.0%" and replacing it with ".5%".

                (e) Section 5.1 of the Credit Agreement shall be amended as
follows:

                        (1) Section 5.1(a) of the Credit Agreement is hereby
amended by deleting the first word of such Section and adding the words "Except
as set forth on Schedule 5.1, the" before the second word thereof.

                        (2) Section 5.1(c) is hereby amended by deleting the
first word of such Section and inserting the words "Except as set forth on
Schedule 5.1, the" before the second word thereof.

                (f) Section 5.3 of the Credit Agreement shall be amended by
deleting the last three sentences thereof in their entirety and replacing them
with "The Company has no subsidiaries except IMPAQ, Countrywide Dental, Inc.,
Travel Too and CPC. None of IMPAQ, Countrywide Dental, Inc. or Travel Too have
any Subsidiaries. CPC has two wholly owned Subsidiaries, CSC and CMC. IMPAQ
owns a 50% interest in RSVP".

                (g) Section 5.8 of the Credit Agreement shall be amended by
deleting the first word of such Section and adding the words "Except as set
forth on Schedule 5.8, neither" before the second word thereof.

                (h) Section 5.9(a) of the Credit Agreement shall be amended by
deleting the first word of such Section and adding the words "Except as set
forth on Schedule 5.9, the" before the second word thereof and by deleting the
words "and none of such property is subject to any Lien" in their entirety.


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                (i) Section 5.17 shall be amended by deleting the reference to 
the Shareholder Pledge Agreement in the first sentence thereof.

                (j) Section 5.19 of the Credit Agreement shall be amended by
deleting the first word of such Section and adding the words "Except as set
forth on Schedule 5.19, since" immediately before "June 30, 1994."

                (k) Schedule 5.1, attached hereto, is hereby added to the
Credit Agreement.

                (l) Schedule 5.7 to the Credit Agreement is hereby deleted in
its entirety and replaced with Schedule 5.7 attached hereto.

                (m) Schedule 5.8, attached hereto is hereby added to the Credit
Agreement.

                (n) Schedule 5.9, attached hereto, is hereby added to the
Credit Agreement.

                (o) Schedule 5.18 to the Credit Agreement is hereby deleted in
its entirety and replaced with Schedule 5.18 attached hereto.

                (p) Schedule 5.19, attached hereto, is hereby added to the
Credit Agreement.

                (q) Exhibits D and E to the Credit Agreement are hereby deleted
in their entirety.

        SECTION 3. RELEASE OF SHAREHOLDER GUARANTEE AND SHAREHOLDER PLEDGE
AGREEMENT. The Collateral Agent hereby confirms that it has, with the
permission of all of the Lenders, released the Shareholders from the
Shareholder Guarantee and the Shareholder Pledge Agreement and returned all
collateral pledged under the Shareholder Pledge Agreement.

        SECTION 4. REPRESENTATIONS AND WARRANTIES; NO DEFAULT. The Company
represents and warrants to the Lenders and the Agent that (i) the
representations and warranties set forth in the Credit Agreement (as amended
hereby) are true and complete on the date hereof as if made on and as of the
date hereof (or, if any such representation or warranty is expressly stated to
have been made as of a specific date, as of such specific date).

        SECTION 5. CONDITIONS PRECEDENT. As provided in Section 2 above, the
amendment to the Credit Agreement set forth in said Section 2 shall become
effective, as of the date hereof, upon the satisfaction of the following
conditions precedent:

        (a) Execution by All Parties. This Amendment No. 1 shall have been
executed and delivered by each of the parties hereto.


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        (b) Note. A Note payable to the order of Brown Brothers Harriman & Co.
in the principal amount of $7,000,000 shall have been executed and delivered by
the Company.

        (c) Subsidiary Guarantee. A Subsidiary Guarantee, in the form of
Exhibit F to the Credit Agreement, shall be executed by each of CPC, CMC, CSC
and Travel Too guaranteeing, on a joint and several basis, the payment of the
Obligations.

        (d) Subsidiary Security Agreement. Subsidiary Security Agreements, in
the form of Exhibit G to the Credit Agreement, shall be executed by each of
CPC, CMC, CSC and Travel Too securing each such Subsidiaries' obligations under
the Subsidiary Guarantee.

        (e) Amendment No. 2 to Security Agreement. Amendment No. 2 to the
Security Agreement shall have been executed and delivered by the parties hereto.

        (f) Supporting Documents. The Agent shall have received, with
sufficient copies for each Lender, the following documents, each of which shall
be satisfactory to the Agent and the Lenders in form and substance:

                (1) Corporate Documents. The following documents, each certified
as indicated below:

                        (A) a copy of any amendments to the charter of the
                Company since April 8, 1996, certified by the Secretary of State
                of Delaware; and

                        (B) a certificate of the Secretary or an Assistant
                Secretary of the Company dated as of a recent date and
                certifying (i) that attached thereto is a true and complete copy
                of resolutions duly adopted by the board of directors of the
                Company authorizing the execution, delivery and performance of
                this Amendment No. 1 and the Credit Agreement as amended hereby
                and that such resolutions have not been modified, rescinded or
                amended and are in full force and effect, (ii) that the charter
                of the Company has not been amended since the date of the
                certification thereto furnished pursuant to clause (A) above and
                that the by-laws of the Company have not been amended since the
                date a certified copy thereof was delivered pursuant to
                subsection 4.1(f) of the Credit Agreement, and (iii) as to the
                incumbency and specimen signature of each officer of the Company
                executing this Amendment No. 1.
 
                        (C) a certificate of the Secretary or an Assistant
                Secretary of each of CPC, CMC, CSC and Travel Too certifying as
                to the incumbency and specimen signatures of each officer
                authorized to sign on its behalf the related Documents to which


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                it is a party and to which are attached copies, certified to be
                true, correct and complete and in full force and effect of (i)
                its charter, (ii) its by-laws and (iii) resolutions of its Board
                of Directors authorizing its execution delivery and performance
                of the Related Documents to which it is a party.

                        (D) Good Standing certificates for the Company, and each
                of CPC, CMC, CSC and Travel Too from the Secretary of the State
                of their respective jurisdictions of incorporation.

                        (E) an opinion of counsel to each of the Company, CPC,
                CMC, CSC and Travel Too that this Amendment and each of the
                Related Documents being executed in connection herewith to which
                it is a party are within its corporate power and authority, have
                been duly authorized, executed and delivered and constitute its
                legal, valid, binding and enforceable obligation.

                (2) Other Documents. Such other documents (including any Form
        UCC Financing Statements) as the Agent or any Lender may reasonably
        request.

        (g) Fees and Expenses.

                (1) Upon execution of this Amendment No. 1, the Company shall
        pay to the Agent for its own account a closing fee of $20,000.

                (2) The Company shall have paid to the Agent all reasonable
        out-of-pocket expenses, including the fees and disbursements of Rogers &
        Wells, counsel to the Agent, incurred by the Agent in connection with
        the preparation, execution and delivery of Amendment No. 1 and each of
        the other documents and instruments contemplated hereby

        SECTION 6. MISCELLANEOUS. Except as herein provided, the Credit
Agreement shall remain unchanged and in full force and effect. This Amendment
No. 1 may be executed in any number of counterparts, all of which taken
together shall constitute one and the same amendatory instrument and any of the
parties hereto may execute this Amendment No. 1 by signing any such
counterpart. THIS AMENDMENT NO. 1 SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.


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        IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 1
to be duly executed and delivered as of the day and year first above written.

                                     MEMBERWORKS INCORPORATED

                                     By: /s/ James B. Duffy
                                         --------------------------------
                                         Name:  James B. Duffy
                                         Title: Treasurer and Secretary


                                     per pro BROWN BROTHERS HARRIMAN & CO.,
                                         as Agent, Collateral Agent and Lender

                                         /s/ W. Carter Sullivan III
                                         --------------------------------
                                         Name:  W. Carter Sullivan III
                                         Title: Senior Manager   
                                         


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                              FINANCIAL CONDITION

(a) The Company restated is financial statements in 1996 (the "1996
    Restatement") which restatement affected the financial statements for years
    1992 - 1995.

(b) The projections were affected as a result of the 1996 Restatement and should
    not be relied upon.



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                                  SCHEDULE 5.7

                              MATERIAL LITIGATION

The lawsuit involving Thomas St. Denis was settled and dismissed.




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                                  SCHEDULE 5.8

                                   NO DEFAULT

The representation and warranties in the Related Documents are not being updated
for purposes of this Amendment No. 1 to the Amended and Restated Credit
Agreement.


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                                  SCHEDULE 5.9

                                     LIENS

1. Liens disclosed by UCC-1 Financing Statements of record.

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                                 SCHEDULE 5.18

                         LIST OF EMPLOYMENT AGREEMENTS

The Agreement dated as of July 31, 1989 between the Company and Thomas St. Denis
was terminated and the Company was released from further obligations thereunder
pursuant to the settlement of the litigation referenced in SCHEDULE 5.7.


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                                   DIVIDENDS

In connection with the Company's initial public offering, the Company redeemed
the Series E and F Preferred Stock and paid all dividends accrued and unpaid
thereon.


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