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                                                                    Exhibit 10.3




June 15, 2001

Mary Ann Packo
301 West 57th Street, #22-D
New York, NY 10019

        Re:     Severance Agreement

        This letter agreement sets forth the terms and conditions under which
you shall be entitled to a severance payment from Jupiter Media Metrix, Inc.
(the "Company"). Please sign your name at the end of this letter agreement,
which shall evidence your agreement to the terms and conditions contained
herein.

        In the event that the Company (or a successor entity) terminates your
employment without "Cause" (as defined below) at any time prior to June 15, 2003
or in the event that you terminate your employment for "Good Reason" (as defined
below) at any time prior to June 15, 2003, you shall be entitled to receive a
severance payment equal to twelve months of your base salary at the rate in
effect on the date of termination. The Company (or successor entity) shall pay
such severance amount, at its option, either (i) in a lump sum payment within 30
days following the termination of employment or (ii) over the twelve-month
severance period (or shorter period) in accordance with the Company's customary
pay practices and subject to all required withholding.

        Termination by you for "Good Reason" shall mean your resignation within
60 days of the any of the following events (the "Trigger Events"):

                (i)     a material reduction in your duties and
                        responsibilities;

                (ii)    a material reduction in your salary or bonus (except in
                        the event of a broad reduction affecting the salaries or
                        bonuses of all or most of the Company's (or successor
                        entity's) senior executives);

                (iii)   a change in your reporting relationship so that you no
                        longer report directly to the chief operating officer,
                        president or chief executive officer of the Company (or
                        successor entity); or

                (iv)    a relocation of your primary worksite to a location
                        outside New York City.


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        You agree to give the Company thirty days' written notice and
opportunity to cure prior to resigning for "Good Reason."

        "Cause" is defined as (i) your conviction of any felony or crime of
moral turpitude; (ii) gross negligence or willful misconduct by you in
connection with your position with the Company; or (iii) your willful and
material breach of your Confidentiality and Noncompetition Agreement.

        This letter agreement constitutes an integrated, written contract,
expressing the entire agreement between us with respect to the subject matter
hereof. In this regard, you agree that you are not relying on any promises or
representations which do not appear in this letter agreement. We further agree
that this letter agreement can be amended or modified only by a written
agreement, signed by each of us.


                                            JUPITER MEDIA METRIX, INC.


                                            By: /s/ Tod Johnson
                                                ------------------------------
                                                Name: Tod Johnson
                                                Title: Chief Executive Officer


Agreed to and acknowledged by:


 /s/ Mary Ann Packo
--------------------------
Mary Ann Packo



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