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                                                                Exhibit 10.2 (o)

July 19, 2000

Ms. Melissa Viglielmo
954 South Pine Creek Road
Fairfield, CT 06430

Dear Melissa,

We are pleased to offer you the position of Vice President - Strategy, Marketing
and Communications, reporting to the CEO, G.M. O'Connell with a starting date
expected to be on or about August 7, 2000.

The following outlines the specifics regarding your compensation, if you accept
this position.

 .  Your annual base salary on your start date will be $220,000.

 .  You will be eligible for a merit bonus that will be calculated using the
   standard methods similarly applied to other members of the management team,
   with a target bonus of 40% of your annual base salary. Such bonus is
   dependent upon your performance, the overall financial performance of Modem
   Media, and is at the discretion of Modem Media's senior management.

 .  Following your commencement of employment and pending approval of the Modem
   Media Compensation Committee, you will be eligible for a 50,000 stock
   option grant. The exercise price of the granted options will be the current
   fair market value on your date of grant and the options will vest over a
   three-year period with the first 33% vesting on one year from the grant
   date.

 .  You will be eligible for 4 weeks of paid vacation in each calendar year.

 .  You will be allowed to be a member of the Board of Directors of an external
   company of organization as long as such company is not a competitor or
   client of Modem Media and that your acceptance of such position does not
   conflict with Modem's Conflict of Interest Policy.

 .  Provided you begin your employment prior to August 8, 2000, you will be
   entitled to participate in the open enrollment of the Employee Stock
   Purchase Plan (ESPP) on August 10, 2000 provided participation is exercised
   within the outlined company enrollment period.

 .  If your employment is terminated involuntarily by Modem Media other than
   for Cause, you will be paid the equivalent of 12 months of your then
   current base salary as severance.

 .  If, within 18 months following a Change of Control, your employment is
   terminated involuntarily by Modem Media other than for Cause or by you for
   Good Reason, the options granted herein will immediately vest effective
   upon the date of termination.

 .  For purposes of this letter, "Change of Control" shall mean the occurrence
   of any one of the following events: (i) the consummation of a merger or
   consolidation of Modem
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   Media with any other corporation, other than a merger or consolidation
   which would result in the voting securities of Modem Media outstanding
   immediately prior thereto continuing to represent (either by remaining
   outstanding or by being converted into voting securities of the surviving
   entity) at least fifty percent (50%) of the total voting power represented
   by the voting securities of Modem Media or such surviving entity
   outstanding immediately after such merger or consolidation and (ii) the
   consummation of the sale or disposition by Modem Media of all or
   substantially all of Modem Media's assets, or (iii) any person (as such
   term is used in Sections 13(d) of the Securities Exchange Act of 1934, as
   amended) becomes the beneficial owner (as defined in Rule 13d-3 under said
   Act), directly or indirectly, of securities of Modem Media representing
   fifty percent (50%) or more of the total voting power represented by Modem
   Media's then outstanding voting securities (excluding any beneficial owner,
   as of the date of the grant, of at least 50% of the total voting power
   represented by Modem Media's outstanding voting securities).

 .  For purposes of this letter, "Cause" shall mean (A) intentional misconduct
   in the performance of duties with Modem Media, (including violation of
   Modem Media's policies or agreements relating to noncompetition or
   confidentiality); (B) failure (other than due to Disability) to
   substantially perform the duties of one's job; (C) engaging in illegal
   conduct (other than any misdemeanor, traffic violation or similar
   misconduct) in connection with the performance of duties for Modem Media;
   or (D) commission of a felony.

 .  For purposes of this letter, "Good Reason" shall mean a material reduction
   in your compensation or/and employee benefits; material reduction in your
   job responsibilities or position; or relocation of your work location by
   more than fifty (50) miles.

Melissa, we are looking forward to your joining Modem Media and playing a key
role in our continued success.  I am certain that the talents which you bring to
the organization will prove instrumental in our future growth.

Best Regards,

/s/   Amy Nenner                      Accepted By:  /s/ Melissa Viglielmo
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VP, Human Resources