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                                                                    EXHIBIT 10.3

               AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT
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         THIS AMENDED AND RESTATED EXECUTIVE SEVERANCE AGREEMENT ("Agreement")
by and between CMGI, Inc., a Delaware corporation (the "Company"), and George A.
McMillan (the "Executive"), is made as of March 1, 2002.

         WHEREAS, effective as the date hereof, the Executive has been promoted
to the position of Chief Executive Officer of the Company;

         WHEREAS, the Company has determined that appropriate steps should be
taken to reinforce and encourage the continued employment and dedication of the
Executive;

         WHEREAS, the Company and the Executive are parties to an Executive
Severance Agreement dated as of June 11, 2001; and

         WHEREAS, the parties desire to amend and restate the Executive
Severance Agreement;

         NOW, THEREFORE, as an inducement for and in consideration of the
Executive remaining in its employ, the Company agrees that the Executive shall
receive the severance benefits set forth in this Agreement in the event the
Executive's employment with the Company is terminated under the circumstances
described below; and for good and valuable consideration, the receipt of which
is hereby acknowledged, the parties agree that the Executive Severance Agreement
be and hereby is amended and restated in its entirety as follows:

1.       Term of Agreement.  The term of this Agreement shall be June 11, 2001
through the last day of Executive's employment with the Company.

2.       Not an Employment Contract. The Executive acknowledges that this
Agreement does not constitute a contract of employment or impose on the Company
any obligation to retain the Executive as an employee and that this Agreement
does not prevent the Executive from terminating his employment. Executive
understands and acknowledges that he is an employee at will and that either he
or the Company may terminate the employment relationship between them at any
time and for any reason.

3.       Severance Payment.  (a) In the event the employment of the Executive is
terminated by the Company for a reason other than for Cause (as defined below),
or by the Executive for Good Reason (as defined below), the Company shall pay to
the Executive a severance payment equal to 12 months of his then-current monthly
base salary plus target bonus, as in effect on the Executive's last day of
employment, and will reimburse the Executive for cost of COBRA for medical,
dental and vision for 12 months following the Executive's last day of
employment. The severance payment shall be payable in full within 10 business
days after the termination of Executive's employment, unless the parties agree
otherwise. Additionally, in the event that prior to July 9, 2003 there occurs a
termination giving rise to a severance payment by the Company to Executive
pursuant to this Section 3(a), 50% of the then-unvested options to purchase
shares of common stock of the Company pursuant to options granted to Executive
on July 9, 2001 ("Initial Options") shall immediately become exercisable in full
and shall be deemed fully vested.

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Additionally, and not in limitation of the previous sentence, (A) in the event
that prior to February 18, 2004 there occurs a termination giving rise to a
severance payment by the Company to Executive pursuant to this Section 3(a), 25%
of the then-unvested options to purchase shares of common stock of the Company
pursuant to options granted to Executive on February 18, 2002 ("CEO Options")
shall immediately become exercisable in full and shall be deemed fully vested,
and (B) in the event that on or after February 18, 2004 there occurs a
termination giving rise to a severance payment by the Company to Executive
pursuant to this Section 3(a), 50% of the then-unvested CEO Options shall
immediately become exercisable in full and shall be deemed fully vested. In the
event of any termination of employment giving rise to a severance payment
pursuant to this Section 3(a), the Executive shall have the right to exercise
any vested Initial Options and CEO Options following such termination of
employment, unless the options terminate sooner by the terms of the underlying
option agreement, as follows:

                           -        Executive shall have at least 90 days
                                    following the termination date of his
                                    employment to exercise his vested Initial
                                    Options and CEO Options;

                           -        Executive shall be entitled to exercise his
                                    vested Initial Options and CEO Options
                                    following the termination date of his
                                    employment for a number of months following
                                    such termination date equal to the number of
                                    months he worked for the Company (rounded up
                                    to the next month in the event the
                                    Executive's termination date is on or after
                                    the 15th day of the month);

                           -        In no event shall Executive be entitled to
                                    exercise his vested Initial Options and CEO
                                    Options following his termination date for a
                                    period greater than 365 days.

         In the event the severance payment and other such benefits, including
but not limited to Initial Options and CEO Options being accelerated pursuant to
this Section 3(a), are paid to the Executive by the Company pursuant to this
Section 3(a), then Section 3(b) shall not apply and shall have no further force
or effect.

         (b) In the event the employment of the Executive is terminated by the
Company for a reason other than for Cause within twelve (12) months following a
Change of Control (as defined below) of the Company or by the Executive for Good
Reason within twelve (12) months following a Change of Control of the Company,
the Company shall pay to the Executive a severance payment equal to 24 months of
his then-current monthly base salary plus target bonus, as in effect on the
Executive's last day of employment, and will reimburse the Executive for cost of
COBRA for medical, dental and vision for 18 months following the Executive's
last day of employment. The severance payment shall be payable in full within 10
business days after the termination of Executive's employment, unless the
parties agree otherwise. Additionally, in the event of a termination giving rise
to a severance payment by the Company to Executive pursuant to this Section
3(b), each outstanding option to purchase shares of common stock of the Company
then held by the Executive shall immediately become exercisable in full and
shall be deemed fully vested. In the event of any termination of employment
giving rise to a severance payment pursuant to this Section 3(b), with respect
to Initial Options and CEO Options, the

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Executive shall have the right to exercise any vested Initial Options and CEO
Options within a 12-month time period following such termination of employment,
unless the options terminate sooner by the terms of the underlying option
agreement. All other options shall be exercisable in accordance with their
terms. In the event the severance payment and other such benefits (including but
not limited to options being accelerated pursuant to this Section 3(b)) are paid
to the Executive by the Company pursuant to this Section 3(b), then Section 3(a)
shall not apply and shall have no further force or effect.

      (c)   The Executive agrees that prior to payment of the severance payment
pursuant to this Section 3 and prior to the provision of benefits and
acceleration of stock options called for by Section 3, Executive shall execute a
release, based on the Company's standard form (including mutual confidentiality
and non-disparagement provisions), of any and all claims he may have against the
Company and its officers, directors, employees and affiliates, except for his
right to enforce any post-employment obligations to him, including obligations
of the Company under this Agreement and stock option agreements, and
indemnification in his capacity as an officer, director or otherwise of the
Company and its affiliates. Executive understands and agrees that the payment of
the severance payment, provision of benefits and the acceleration of options
called for by Section 3 are contingent on his execution of the previously
described release of claims. The payment to the Executive of the amounts payable
under this Section 3 (and acceleration of options, if applicable) shall
constitute the sole remedy of the Executive in the event of a termination of the
Executive's employment.

      (d)   In the event that any amounts payable to the Executive pursuant to
this Section 3 are characterized as "excess parachute payments" pursuant to
Section 4999 of the Internal Revenue Code of 1986, as amended (the "Code"), then
the Executive may elect to reduce the amounts payable to the Executive hereunder
or to have a portion of the stock options not vest in order to avoid any "excess
parachute payment" under Section 280G(b)(1) of the Code; provided that any such
election shall not adversely affect the Company. Unless the parties hereto
otherwise agree in writing, any determination required under this Section 3(d)
shall be made in writing by independent public accountants reasonably agreed to
by the parties hereto (the "Accountants"), whose determination shall be
conclusive and binding upon the parties for all purposes. For purposes of making
the calculations required by this Section 3(d), the Accountants may rely on
reasonable, good faith interpretations concerning the application of Section
280G and Section 4999 of the Code. The parties agree to furnish to the
Accountants such information and documents as the Accountants may reasonably
request in order to make the required determinations. The Executive shall bear
all fees and expenses the Accountants may reasonably charge in connection with
the services contemplated by this Section 3(d).

4.       Definitions.  For purposes of this Agreement, the following terms shall
have the following meanings:

         (a) "Cause" shall mean a good faith finding by the Board of Directors
of the Company, after giving Executive an opportunity to be heard, of: (i)
dishonest, gross negligent or willful misconduct by Executive in connection with
his employment duties, (ii) continued failure by Executive to perform his duties
or responsibilities required pursuant to his employment, after written notice
and an opportunity to cure, (iii) mis-appropriation by Executive of the assets
or business opportunities of the Company, or its affiliates, (iv) embezzlement
or other financial or

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other fraud committed by Executive, (v) the Executive knowingly allowing any
third party to commit any of the acts described in any of the preceding clauses
(iii) or (iv), or (vi) the Executive's indictment for, conviction of, or entry
of a plea of no contest with respect to, any felony or any crime involving moral
turpitude.

     (b)  "Good Reason" shall mean: (i) the unilateral relocation by the Company
of the Executive's principal work place for the Company to a site more than 60
miles from Andover, Massachusetts, (ii) a reduction in the Executive's (A)
then-current base salary without the Executive's consent, or (B) target bonus or
a material reduction in benefits without the Executive's consent, or unless
other executive officers are similarly treated, (iii) material diminution of
Executive's duties, authority or position as Chief Executive Officer of the
Company, without the Executive's consent, (iv) any amendment following the date
hereof to the officer indemnification provisions contained in Article Ninth of
the Company's certificate of incorporation that materially reduces the
indemnification benefits to the Executive, or (v) death or permanent and total
disability (as defined in Section 22(e)(3) of the Code) of the Executive.

     (c)  "Change of Control" shall mean the first to occur of any of the
following: (a) any "person" or "group" (as defined in the Securities Exchange
Act of 1934) becomes the beneficial owner of a majority of the combined voting
power of the then outstanding voting securities with respect to the election of
the Board of Directors of the Company; (b) any merger, consolidation or similar
transaction involving the Company, other than a transaction in which the
stockholders of the Company immediately prior to the transaction hold
immediately thereafter in the same proportion as immediately prior to the
transaction not less than 50% of the combined voting power of the then voting
securities with respect to the election of the Board of Directors of the
resulting entity; or (c) any sale of all or substantially all of the assets of
the Company.

5.   Termination of Employment. Upon termination of Executive's employment with
the Company for any reason, in addition to any severance payments or other
benefits which may be payable under Section 3 of this Agreement, Executive shall
be entitled to receive all salary and benefits through the last day of his
employment. In addition, in the event the Executive is terminated for other than
Cause or the Executive terminates his employment for Good Reason, Executive
shall be entitled to a pro rata share of his earned target bonus, such earned
target bonus to be determined in accordance with the terms and provisions of the
Executive's target bonus plan.

6.   Miscellaneous.

     (a)  Notices. Any notices delivered under this Agreement shall be deemed
duly delivered four business days after it is sent by registered or certified
mail, return receipt requested, postage prepaid, or one business day after it is
sent for next-business day delivery via a reputable nationwide overnight courier
service, in each case to the address of the recipient set forth in the
introductory paragraph hereto. Either party may change the address to which
notices are to be delivered by giving notice of such change to the other party.
All notices to the Company shall also be addressed to the Company's General
Counsel.

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     (b)  Pronouns. Whenever the context may require, any pronouns used in this
Agreement shall include the corresponding masculine, feminine or neuter forms,
and the singular forms of nouns and pronouns shall include the plural, and vice
versa.

     (c)  Entire Agreement. This Agreement constitutes the entire agreement
between the parties and supersedes all prior agreements and understandings,
whether written or oral, relating to the subject matter of this Agreement.

     (d)  Amendment. This Agreement may be amended or modified only by a written
instrument executed by both the Company and the Executive.

     (e)  Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts. Any action, suit
or other legal arising under or relating to any provision of this Agreement
shall be commenced only in a court of the Commonwealth of Massachusetts (or, if
appropriate, a federal court located within Massachusetts), and the Company and
the Executive each consents to the jurisdiction of such a court. The Company and
the Executive each hereby irrevocably waive any right to a trial by jury in any
action, suit or other legal proceeding arising under or relating to any
provision of this Agreement.

     (f)  Successors and Assigns. This Agreement shall be binding upon and inure
to the benefit of both parties and their respective successors and assigns,
including any corporation with which or into which the Company may be merged or
which may succeed to its assets or business, provided, however, that the
obligations of the Executive are personal and shall not be assigned by him or
her.

     (g)  Waivers. No delay or omission by the Company in exercising any right
under this Agreement shall operate as a waiver of that or any other right. A
waiver or consent given by the Company on any one occasion shall be effective
only in that instance and shall not be construed as a bar or waiver of any right
on any other occasion.

     (h)  Captions. The captions of the sections of this Agreement are for
convenience of reference only and in no way define, limit or affect the scope or
substance of any section of this Agreement.

     (i)  Severability. In case any provision of this Agreement shall be
invalid, illegal or otherwise unenforceable, the validity, legality and
enforceability of the remaining provisions shall in no way be affected or
impaired thereby.

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THE EXECUTIVE ACKNOWLEDGES THAT HE HAS CAREFULLY READ THIS AGREEMENT AND
UNDERSTANDS AND AGREES TO ALL OF THE PROVISIONS IN THIS AGREEMENT.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the day and year set forth above.

                              CMGI, Inc.

                              By: /s/ Jeffrey Yanagi

                              Title: EVP Human Resources


                              /s/ George A. McMillan
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                              George A. McMillan

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