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                                                                Exhibit 10.23



                              EMPLOYMENT AGREEMENT

      This Employment Agreement (the "Agreement"), made and entered into this
19th day of September, 2000, by and between Jupiter Communications, Inc., a
Delaware corporation (the "Company"), and Kurt Abrahamson (the "Executive").

                                   WITNESSETH

      WHEREAS, pursuant to an Agreement and Plan of Merger and Reorganization
dated June 26, 2000, (the "Merger Agreement"), a subsidiary of Media Metrix,
Inc. ("Media Metrix") is to be merged with and into the Company (the "Merger");

      WHEREAS, the Executive is a significant shareholder in the Company, will
receive substantial consideration in connection with the Merger and desires the
Merger to occur;

      WHEREAS, the Executive's agreement to the terms and conditions contained
herein is a condition of Media Metrix' execution of the Merger Agreement;

      WHEREAS, the Executive has served as President and Chief Operating Officer
of the Company and the parties wish that he continue to serve as an officer of
Media Metrix following the closing of the Merger;

      WHEREAS, the Executive shall be employed by Media Metrix upon the
closing of the Merger; and

      WHEREAS, the Executive and the Company desire to enter into a formal
Employment Agreement to set forth the terms and conditions of the Executive's
employment with Media Metrix upon the closing of the Merger.

      NOW, THEREFORE, in consideration of the mutual promises, terms,
provisions, and conditions contained herein, the parties agree as follows:

1.    Position.

            Upon the closing of the Merger, the Executive will assume the
position of Group President for Media Metrix reporting directly to Media Metrix'
President and performing duties commensurate with such position. The Executive
shall perform his duties diligently and faithfully and shall devote his full
business time and attention to such duties, provided that the Executive may
devote time and attention to personal financial matters and charitable
activities.

2.    Term of Agreement and Renewal.

            This Agreement will become effective and the term of Executive's
employment under this Agreement will commence on the date of the closing of the
Merger (the "Effective Date"). Subject to the provisions of Section 8 of this
Agreement, the term of Executive's employment hereunder shall be for an initial
term of three (3) years from the Effective Date (the "Initial Term"). The
Initial Term of this Agreement shall be automatically extended for successive
one (1) year periods (each a "Renewal Period") unless the Company or the
Executive
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gives written notice to the other at least ninety (90) days prior to the
expiration of the Initial Term, or a Renewal Period, of such party's election
not to extend this Agreement. References herein to the "Term" shall mean the
Initial Term as it may be so extended by one or more Renewal Periods. The last
day of the Term is the "Expiration Date."

3.    Compensation and Benefits.

            (a) Salary. Commencing on the Effective Date, the Company agrees to
pay the Executive a base salary at an initial annual rate of Two Hundred
Thousand Dollars ($200,000), payable in such installments as is the policy of
the Company (the "Salary"), but no less frequently than monthly. Thereafter, the
Board of Directors of Media Metrix (the "Board") shall determine appropriate
increases to Executive's Salary but in no event shall diminish the amount of
Executive's Salary below the initial annual rate, or below any increased rates
unless all of the Executive's peer executives undergo comparable decreases.

            (b) Bonus. The Executive shall receive a guaranteed annual bonus of
Twenty Five Percent (25%) of the annual Salary (pro rated for any partial
calendar years worked by the Executive during the Term), and shall be eligible
for an additional annual bonus amount of up to Fifteen Percent (15%) of the
Salary (pro rated for any partial calendar years worked by the Executive during
the Term) based on his achievement of reasonable performance goals to be agreed
upon by the Company and the Executive on or about the Effective Date and at the
commencement of each calendar year during the Term.

            (c) Benefits. The Executive shall be entitled to participate in all
employee benefit plans which the Company provides or may establish from time to
time for the benefit of its employees, including, without limitation, group
life, medical, surgical, dental and other health insurance, short and long-term
disability, deferred compensation, profit-sharing, paid vacation and similar
benefits.

            (d) Stock Options. As of the Effective Date, but immediately prior
to the Merger, the Company shall grant the Executive, pursuant to the Company's
Stock Option Plan, an option to purchase Forty Five Thousand (45,000) shares of
the Company's common stock at a purchase price equal to the fair market value of
the shares at the time of the grant, vesting as to 25% of the option shares on
the first anniversary of the grant, and in thirty six (36) equal monthly
installments thereafter, in each case as long as the Executive is employed by
the Company on such vesting date.

            (e) Expenses. The Company shall pay or reimburse the Executive for
all reasonable out-of-pocket expenses actually incurred by him during the Term
in performing services hereunder, provided that the Executive properly accounts
for such expenses in accordance with the Company's policies.

4.    Confidentiality, Disclosure of Information.

            (a) The Executive recognizes and acknowledges that the Executive has
had and will have access to Confidential Information (as defined below) relating
to the business or interests of the Company or of persons with whom the Company
may have business relationships. The Executive will not during the Term, or at
any time thereafter, use, disclose or


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permit to be known by any other person or entity, any Confidential Information
of the Company (except as required by applicable law or in connection with the
performance of the Executive's duties and responsibilities hereunder). The term
"Confidential Information" means information relating to the Company's business
affairs, proprietary technology, trade secrets, patented processes, research and
development data, know-how, market studies and forecasts, competitive analyses,
pricing policies, employee lists, employment agreements (other than this
Agreement), personnel policies, the substance of agreements with customers,
suppliers and others, marketing arrangements, customer lists, commercial
arrangements, or any other information relating to the Company's business that
is not generally known to the public or to actual or potential competitors of
the Company (other than through a breach of this Agreement). This obligation
shall continue until such Confidential Information becomes publicly available,
other than pursuant to a breach of this Agreement by the Executive, regardless
of whether the Executive continues to be employed by the Company.

            (b) It is further agreed and understood by and between the parties
to this Agreement that all "Company Materials," which include, but are not
limited to, computers, computer software, computer disks, tapes, printouts,
source, HTML and other code, flowcharts, schematics, designs, graphics,
drawings, photographs, charts, graphs, notebooks, customer lists, sound
recordings, other tangible or intangible manifestation of content, and all other
documents whether printed, typewritten, handwritten, electronic, or stored on
computer disks, tapes, hard drives, or any other tangible medium, as well as
samples, prototypes, models, products and the like, shall be the exclusive
property of the Company and, upon termination of Executive's employment with the
Company, and/or upon the request of the Company, all Company Materials,
including copies thereof, as well as all other Company property then in the
Executive's possession or control, shall be returned to and left with the
Company.

5.    Inventions Discovered by Executive.

            The Executive shall promptly disclose to the Company any invention,
improvement, discovery, process, formula, or method or other intellectual
property, whether or not patentable or copyrightable (collectively,
"Inventions"), conceived or first reduced to practice by the Executive, either
alone or jointly with others, while performing services hereunder (or, if based
on any Confidential Information, at any time during or after the Term), (a)
which pertain to any line of business activity of the Company, whether then
conducted or then being actively planned by the Company, with which the
Executive was or is involved, (b) which is developed using time, material or
facilities of the Company, whether or not during working hours or on the Company
premises, or (c) which directly relates to any of the Executive's work during
the Term, whether or not during normal working hours. The Executive hereby
assigns to the Company all of the Executive's right, title and interest in and
to any such Inventions. During and after the Term, the Executive shall execute
any documents necessary to perfect the assignment of such Inventions to the
Company and to enable the Company to apply for, obtain and enforce patents,
trademarks and copyrights in any and all countries on such Inventions,
including, without limitation, the execution of any instruments and the giving
of evidence and testimony, without further compensation beyond the Executive's
agreed compensation during the course of the Executive's employment. Without
limiting the foregoing, the Executive further acknowledges that all original
works of authorship by the Executive, whether created alone or jointly with
others, related to the Executive's employment with the Company and which are
protectable by


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copyright, are "works made for hire" within the meaning of the United States
Copyright Act, 17 U.S.C. Section 101, as amended, and the copyright of which
shall be owned solely, completely and exclusively by the Company. If any
Invention is considered to be work not included in the categories of work
covered by the United States Copyright Act, 17 U.S.C. Section 101, as amended,
such work is hereby assigned or transferred completely and exclusively to the
Company. The Executive hereby irrevocably designates counsel to the Company as
the Executive's agent and attorney-in-fact to do all lawful acts necessary to
apply for and obtain patents and copyrights and to enforce the Company's rights
under this Section. This Section 5 shall survive the termination of this
Agreement. Any assignment of copyright hereunder includes all rights of
paternity, integrity, disclosure and withdrawal and any other rights that may be
known as or referred to as "moral rights" (collectively "Moral Rights"). To the
extent such Moral Rights cannot be assigned under applicable law and to the
extent the following is allowed by the laws in the various countries where Moral
Rights exist, the Executive hereby waives such Moral Rights and consents to any
action of the Company that would violate such Moral Rights in the absence of
such consent. The Executive agrees to confirm any such waivers and consents from
time to time as requested by the Company.

6.    Non-Competition and Non-Solicitation.

            The Executive acknowledges that the Company has invested substantial
time, money and resources in the development and retention of its customers,
accounts, business partners, Inventions and other Confidential Information
(including trade secrets), and further acknowledges that during the course of
the Executive's employment with the Company the Executive has had and will have
access to the Company's Inventions and Confidential Information (including trade
secrets), and will be introduced to existing and prospective customers, accounts
and business partners of the Company.

            In recognition of this, the Executive covenants and agrees that:

            (a) During the Term, and for a period of two (2) years thereafter,
the Executive may not, without the prior written consent of the Company,
(whether as an employee, agent, servant, owner, partner, consultant, independent
contractor, representative, stockholder or in any other capacity whatsoever)
participate in any business that offers products or services directly
competitive with those offered by the Company (a "Business"). Notwithstanding
the foregoing, the Executive shall be permitted to consult for or be employed by
an entity engaging in a Business during the two year post-employment
non-competition period if he works for a independently-managed and operated
subsidiary, affiliate or division of such entity that does not engage in a
Business and does not perform any services for the aspects of such entity
engaging in a Business. Nothing herein shall prevent the Executive from
acquiring or owning 3% or less of any publicly-traded class of securities so
long as the Executive holds such securities as a passive investment.

            (b) During the Term, and for a period of two (2) years thereafter,
the Executive may not entice, solicit or encourage any Company employee to leave
the employ of the Company or any independent contractor to sever its engagement
with the Company, absent prior written consent to do so from the Company.


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            (c) During the Term, and for a period of two (2) years thereafter,
the Executive may not, directly or indirectly, entice, solicit or encourage any
customer or prospective customer of the Company to cease doing business with the
Company, reduce its relationship with the Company or refrain from establishing
or expanding a relationship with the Company, absent prior written consent to do
so from the Company.

7.    Provisions Necessary and Reasonable.

            (a) The Executive agrees that (i) the provisions of Sections 4, 5
and 6 of this Agreement are necessary and reasonable to protect the Company's
Confidential Information, Inventions, and goodwill; (ii) the specific temporal,
geographic and substantive provisions set forth in Section 6 of this Agreement
are reasonable and necessary to protect the Company's business interests; and
(iii) in the event of any breach of any of the covenants set forth herein, the
Company would suffer substantial irreparable harm and would not have an adequate
remedy at law for such breach. In recognition of the foregoing, the Executive
agrees that in the event of a breach or threatened breach of any of these
covenants, in addition to such other remedies as the Company may have at law,
without posting any bond or security, the Company shall be entitled to seek and
obtain equitable relief, in the form of specific performance, and/or temporary,
preliminary or permanent injunctive relief, or any other equitable remedy which
then may be available. The seeking of such injunction or order shall not affect
the Company's right to seek and obtain damages or other equitable relief on
account of any such actual or threatened breach.

            (b) If any of the covenants contained in Sections 4, 5 and 6 hereof,
or any part thereof, are hereafter construed to be invalid or unenforceable, the
same shall not affect the remainder of the covenant or covenants, which shall be
given full effect without regard to the invalid portions.

            (c) If any of the covenants contained in Sections 4, 5 and 6 hereof,
or any part thereof, are held to be unenforceable by a court of competent
jurisdiction because of the temporal or geographic scope of such provision or
the area covered thereby, the parties agree that the court making such
determination shall have the power to reduce the duration and/or geographic area
of such provision and, in its reduced form, such provision shall be enforceable.

            (d) For purposes of Sections 4, 5 and 6 hereof, the "Company" shall
mean Jupiter Communications, Inc. before the closing of the Merger, and Media
Metrix and Jupiter Communications, Inc., and their respective subsidiaries, upon
the closing of the Merger and thereafter.

8.    Termination and Severance.

            Notwithstanding the provisions of Section 2 of this Agreement, the
Executive's employment hereunder may terminate under the following
circumstances:

            (a) Termination by the Company for Cause. The Company may terminate
this Agreement for Cause at any time, upon written notice to the Executive
setting forth in reasonable detail the nature of such Cause. For purposes of
this Agreement, Cause is defined as (i) the Executive's conviction of any felony
or any crime involving moral turpitude; or (ii) the Executive's willful refusal
to perform his duties hereunder or the lawful directives of the Board,


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after thirty (30) days' written notice and opportunity to cure. A termination of
the Executive's employment hereunder for Cause shall occur only through a
majority vote of the Board after the Executive has been afforded an opportunity
to appear before the Board, with counsel, to present his position. Upon the
termination of the Executive's employment hereunder for Cause, the Company shall
have no further obligation or liability to the Executive other than for Salary
and bonus earned under this Agreement prior to the date of termination, and any
accrued but unused vacation.

            (b) Termination by the Company Without Cause. The Executive's
employment hereunder may be terminated without Cause by the Company upon written
notice to the Executive, provided, however, that if the Company terminates the
Executive's employment without Cause, or the Executive terminates his employment
for Good Reason, as defined below, the Company shall, in addition to providing
the payments required upon a termination pursuant to Section 8(a) above, (i)
continue to pay the Executive the Salary and shall provide health coverage,
under the same conditions as exist at the time of termination, for a period of
eighteen (18) months, or until the Expiration Date, whichever is longer; and
(ii) as to stock options granted by the Company to the Executive hereunder or
granted after the Effective Date ("Acceleration Options"), any portion of such
Acceleration Options which is unvested shall accelerate and vest in full, and
the Executive shall be permitted to exercise vested Acceleration Options up to
one (1) year after the effective date of the termination.

            (c) Termination by the Executive. The Executive may terminate his
employment hereunder at any time without Good Reason upon one (1) month's
written notice to the Company. Upon the termination of the Executive's
employment hereunder by the Executive without Good Reason, the Company shall
have no further obligation or liability to the Executive other than for Salary
and bonus earned under this Agreement prior to the date of termination, and any
accrued but unused vacation. The Executive may also terminate his employment
hereunder for "Good Reason," within ninety (90) days of the occurrence of any of
the following events (i) a material breach of this Agreement by the Company;
(ii) a material reduction in the Executive's title, duties or responsibilities
or the assignment to the Executive of duties inconsistent with his position, as
specified in Section 1 hereof; (iii) a change in the Executive's reporting
relationship so that he no longer reports directly to the President, or to the
Chief Executive Officer or the Board of Directors; or (iv) a relocation of the
Executive's worksite to a location outside of New York County, New York. The
Executive shall give the Company thirty (30) days' written notice and
opportunity to cure prior to any termination for Good Reason.

            (d) Death. In the event of the Executive's death during the Term of
this Agreement, the Executive's employment hereunder shall immediately and
automatically terminate, and the Company shall have no further obligation or
duty to the Executive or his estate or beneficiaries other than for the Salary
and bonus earned under this Agreement to the date of termination and any
payments or benefits due under Company policies or benefit plans.

            (e) Disability. The Company may terminate the Executive's employment
hereunder, upon written notice to the Executive, in the event that the Executive
becomes disabled during the Term through any condition of either a physical or
psychological nature and, as a result, is, with or without reasonable
accommodation, unable to perform the essential functions of the services
contemplated hereunder for (a) a period of ninety (90) consecutive days, or (b)
for


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shorter periods aggregating one hundred twenty (120) days during any twelve (12)
month period during the Term. Any such termination shall become effective upon
mailing or hand delivery of notice that the Company has elected its right to
terminate under this subsection 8(e), and the Company shall have no further
obligation or duty to the Executive other than for Salary and bonus earned under
this Agreement prior to the date of termination and any payments or benefits due
under Company policies or benefit plans.

            (f) Effect of Non-Renewal. In the event that the Company gives
notice of its election not to extend the Term of the Agreement for a Renewal
Period pursuant to Section 2 above, such non-renewal shall not be considered a
termination without Cause or an event constituting Good Reason, and the Company
shall continue to pay the Executive full compensation as defined in Section 3 of
this Agreement from the date the Executive receives such notice through the
Expiration Date. The Executive shall not be entitled to any additional
compensation upon such a non-renewal other than any payments or benefits due
under Company policies or benefit plans.

9.    Choice of Law.

            The validity, interpretation and performance of this Agreement shall
be governed by, and construed in accordance with, the internal law of New York,
without giving effect to conflict of law principles.

10.   Miscellaneous.

            (a) Assignment. The parties acknowledge and agree that the rights
and obligations of the Company under this Agreement may be assigned by the
Company to any successors in interest and shall be assigned to and assumed by
Media Metrix upon the closing of the Merger. The Executive further acknowledges
and agrees that this Agreement is personal to the Executive and that the
Executive may not assign any rights or obligations hereunder.

            (b) Withholding. All salary and bonus payments required to be made
by the Company to the Executive under this Agreement shall be subject to all
withholding required by law.

            (c) Entire Agreement. This Agreement sets forth the entire agreement
between the parties and, as of the Effective Date, supersedes any prior
communications, agreements and understandings, written or oral, with respect to
the terms and conditions of the Executive's employment other than any written
agreements executed by the parties in connection with the grant of stock options
to the Executive by the Company.

            (d) Amendments. Any attempted modification of this Agreement will
not be effective unless signed by an officer of the Company and the Executive.

            (e) Waiver of Breach. The Executive understands that a breach of any
provision of this Agreement may only be waived by an officer of the Company. The
waiver by the Company of a breach of any provision of this Agreement shall not
operate or be construed as a waiver of any subsequent breach.


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            (f) Severability. If any provision of this Agreement should, for any
reason, be held invalid or unenforceable in any respect by a court of competent
jurisdiction, then the remainder of this Agreement, and the application of such
provision in circumstances other than those as to which it is so declared
invalid or unenforceable, shall not be affected thereby, and each such provision
of this Agreement shall be valid and enforceable to the fullest extent permitted
by law.

            (g) Notices. Any notices, requests, demands and other communications
provided for by this Agreement shall be in writing and shall be effective when
delivered by private messenger, private overnight mail service, or facsimile as
follows (or to such other address as either party shall designate by notice in
writing to the other in accordance herewith):

            If to the Company:

            21 Astor Place
            New York, New York 10003
            Attention:  General Counsel

            With a copy to:

            Brobeck, Phleger & Harrison LLP
            1633 Broadway
            New York, New York 10019
            Attention:  Richard Gilden

            If to Executive:

            168 Pacific Street
            Brooklyn, New York 11201

            (h) Survival. The Executive and the Company agree that certain
provisions of this Agreement shall survive the expiration or termination of this
Agreement and the termination of the Executive's employment with the Company.
Such provisions shall be limited to those within this Agreement which, by their
express and implied terms, obligate either party to perform beyond the
termination of the Executive's employment or termination of this Agreement.

            (i) Headings. The parties acknowledge that the headings in this
Agreement are for convenience of reference only and shall not control or affect
the meaning or construction of this Agreement.


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


EXECUTIVE                                 JUPITER COMMUNICATIONS, INC.


/s/ Kurt Abrabamson                      By: /s/ Gene DeRose
------------------------------------         ---------------------------------
KURT ABRAHAMSON
                                          Title: Chief Executive Officer
                                                ------------------------------


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