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                                                                  EXHIBIT 10.31

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                             USINTERNETWORKING, INC.
                         EXECUTIVE EMPLOYMENT AGREEMENT


              This Executive Employment Agreement (the "AGREEMENT") dated as of
July 21, 2000 (the "Effective Date"), is made by and between USinternetworking,
Inc., a Delaware corporation (together with any successor thereto, the
"COMPANY") and Andrew A. Stern (the "EXECUTIVE").

              This Agreement supercedes and replaces the Employment Agreement
dated July 27, 1998, between the Executive and the Company, and the amendments
thereto, but is exclusive of the existing option agreements between the
Executive and the Company which shall remain in full force and effect.

              In consideration of the mutual promises made below, the Company
and Executive agree as follows:

              1.     POSITION AND DUTIES

                            The Executive shall, for a period of 3 years from
the Effective Date ("TERM"), serve as Chief Executive Officer of the Company,
reporting to the Executive Committee of the Board of Directors of the Company.
The Executive shall also be appointed, as of the Effective Date, to a
directorship on the Company's Board of Directors and as a member of the
Executive Committee of the Board of Directors. The Executive will serve as a
Class II director until the Annual Meeting of Stockholders in 2001 and until his
successor is duly elected and qualified, or until Executive's earlier death,
resignation or removal. The Executive shall have the duties which are
commensurate and consistent with those of a chief executive officer, including,
but not limited to, strategic direction, leadership and decision-making
authority for all elements of the business of the Company. The Executive hereby
confirms that by accepting this new position and these duties, the Executive is
not violating, and will not violate, any agreements the Executive may have with
any third parties, including former employers.

              2.     COMPENSATION AND OTHER RELATED BENEFITS

                     (a)    Annual Base Salary. During the Term, the Executive
shall receive a base salary at a rate of three hundred twenty-five thousand
dollars ($ 325,000) per annum, subject to increase as determined by the
Compensation Committee ("ANNUAL BASE SALARY"). The Executive's salary shall be
payable in accordance with the Company's normal payroll procedures.

                     (b)    Bonus. The Executive shall be eligible to receive a
discretionary target minimum bonus of one hundred percent (100%) and a maximum
bonus of two hundred percent (200%), of the Executive's Annual Base Salary
assessed as of the last day of each calendar year of the Term and payable in
accordance with the timing of the Company's payment of bonuses to its other
senior executives and no later than April 30th of the following year. Any


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bonus shall be determined in the sole discretion of the Compensation Committee
of the Board of Directors of the Company (the "Compensation Committee") based on
achievement of predetermined performance objectives mutually agreed upon between
the Executive and the Compensation Committee no later than 90 days after the
Effective Date and the commencement of each calendar year of the Term
thereafter.

                     (c)    Stock Options. The Executive shall be granted, as of
the Effective Date:

       (i)    a non-qualified stock option (the "First Option") to purchase five
              hundred thousand (500,000) shares of the Company's common stock
              (subject to adjustment for stock splits and stock dividends), with
              an exercise price equal to the closing price of the Company's
              common stock, as reported on the Nasdaq National Market, on the
              Effective Date. The term of the First Option shall be ten (10)
              years. The First Option shall vest as to 1/12th (rounded to four
              decimal places) of the underlying shares on September 30, 2000,
              and shall vest as to 1/12th (rounded to four decimal places) of
              the underlying shares on the last day of each calendar quarter
              thereafter during the Term until fully vested; and

       (ii)   a non-qualified stock option (the "Performance Option") to
              purchase five hundred thousand (500,000) shares of the Company's
              common stock (subject to adjustment for stock splits and stock
              dividends), with an exercise price equal to the closing price of
              the Company's common stock, as reported on the Nasdaq National
              Market, on the Effective Date. The term of the Performance Option
              shall be ten (10) years. The Performance Option shall vest in full
              on July 20, 2003; provided, however, that, in addition to the
              vesting described above, vesting shall accelerate as follows: 1)
              upon the Executive's death or "Disability" (as defined below), the
              Performance Option shall vest as to 1/12th (rounded to four
              decimal places) of the underlying shares for each of the calendar
              quarters the Executive was employed during the Term of the
              Agreement until his death or Disability; or 2) the achievement by
              the Company of the following milestones during the Term while
              Executive is employed with the Company:

              (A)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on September 30, 2000, if the Company
                     achieves EBITDA of $ (18) Million or better, and has
                     revenues of $32 Million or better, in each case determined
                     as of the Company's fiscal quarter ending September 30,
                     2000 and determined in accordance with generally accepted
                     accounting principles ("GAAP");

              (B)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on December 31, 2000, if the Company
                     achieves EBITDA of $(14) Million or better, and has
                     revenues of $41 Million or better, in each case determined
                     as of the Company's fiscal quarter ending December 31, 2000
                     and determined in accordance with GAAP;


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              (C)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on March 31, 2001, if the Company
                     achieves EBITDA of $(11) Million or better, and has
                     revenues of $50 Million or better, in each case determined
                     as of the Company's fiscal quarter ending March 31, 2001
                     and determined in accordance with GAAP;

              (D)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on June 30, 2001, if the Company achieves
                     EBITDA of $(5) Million or better, and has revenues of $60
                     Million or better, in each case determined as of the
                     Company's fiscal quarter ending June 30, 2001 and
                     determined in accordance with GAAP;

              (E)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on September 30, 2001, if the Company
                     achieves EBITDA of $1 Million or better, and has revenues
                     of $71 Million or better, in each case determined as of the
                     Company's fiscal quarter ending September 30, 2001 and
                     determined in accordance with GAAP;

              (F)    The Performance Option shall vest as to 1/6th of the
                     underlying shares on December 31, 2001, if the Company
                     achieves EBITDA of $4 Million or better, and has revenues
                     of $84 Million or better, in each case determined as of the
                     Company's fiscal quarter ending December 31, 2001 and
                     determined in accordance with GAAP; and

       (iii)  a non-qualified stock option (the "Share Appreciation Option") to
              purchase 750,000 shares of the Company's common stock (subject to
              adjustment for stock splits and stock dividends), with an exercise
              price equal to the closing price of the Company's common stock, as
              reported on the Nasdaq National Market, on the Effective Date. The
              term of the Share Appreciation Option shall be ten (10) years. The
              Share Appreciation Option shall vest in full on July 20, 2005;
              provided, however, that such vesting shall accelerate as follows:

              (A)    The Share Appreciation Option shall vest as to 1/3rd
                     (rounded to four decimal places) of the underlying shares
                     on the first day that the average of the closing prices of
                     the Company's common stock over thirty (30) consecutive
                     calendar days, as reported on the Nasdaq National Market,
                     is equal to or greater than $50.00 per share (split
                     adjusted);

              (B)    The Share Appreciation Option shall vest as to 1/3rd
                     (rounded to four decimal places) of the underlying shares
                     on the first day that the average of the closing prices of
                     the Company's common stock over thirty (30) consecutive
                     calendar days, as reported on the Nasdaq National Market,
                     is equal to or greater than $75.00 per share (split
                     adjusted); and

              (C)    The Share Appreciation Option shall vest as to 1/3rd
                     (rounded to four decimal places) of the underlying shares
                     on the first day that the average of the closing prices of
                     the Company's common stock over thirty (30)


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                     consecutive calendar days, as reported on the Nasdaq
                     National Market, is equal to or greater than $100.00 per
                     share (split adjusted).

              The options will be delivered pursuant to mutually agreed to
Non-Qualified Stock Option Agreements, pursuant to the Company's Amended and
Restated 1998 Stock Option Plan (the "SOP"), to be executed by the Executive and
Company within two (2) weeks of the Effective Date. Notwithstanding anything in
the SOP to the contrary, the Company and the Executive agree that the
pooling-of-interest preservation provisions of Section 9.3(e) of the SOP shall
not apply to the stock options granted pursuant to this Paragraph 2(c). Future
option grants may be made to the Executive at the discretion of the Compensation
Committee of the Company's Board of Directors.

              "DISABILITY" is defined as the failure of Executive to perform the
duties set forth in Paragraph 1 for a cumulative total of sixty percent (60%) or
more of the normal working days during any two (2) consecutive months of the
Term, or failure to perform his duties for ninety (90) or more consecutive days
of the Term. Nothing herein shall be construed to violate any Federal or State
law including the Family and Medical Leave Act of 1993, 29 U.S.C.S. Sections
2601 et seq., and the Americans with Disabilities Act of 1990, 42 U.S.C.S.
Sections 12101 et seq.

                     (d)    Other Benefits. The Executive shall be entitled to
participate in any welfare benefit plans maintained by the Company for similarly
situated executives, which may include medical, dental, vision, disability and
life insurance benefits, and to receive such other fringe benefits and
perquisites as may be granted to senior management of the Company from time to
time. The Company shall provide, at no cost to the Executive, an additional life
insurance policy on the Executive's life with the beneficiary specified by the
Executive and the face amount of which shall be equal to twice the Executive's
Annual Base Salary as of the Effective Date, less any group insurance otherwise
provided pursuant to this Paragraph 2(d). The Executive shall also be entitled
to participate in the Company's 401(k) plan and any other retirement, deferred
compensation or long-term incentive compensation program that the Company may
establish for senior management from time to time. Additionally, the Executive
will be eligible for a reasonable number of days of paid vacation each year of
the Term, at the Executive's discretion.

                     (e)    Other Expenses: In addition to the compensation
provided for above, the Company agrees to pay or to reimburse the Executive
during his employment for all reasonable travel, entertainment and other
expenses which the Executive may incur in regard to the business of the Company
in accordance with and subject to (i) the limitations of the Company's standard
practices and policies and (ii) the Executive's presentation of such documents
and records as the Company shall require from time to time to substantiate such
expenses.

              3.     TERMINATION WITHOUT CAUSE

                     If the Company terminates the Executive's employment
without "Cause" (as defined in Paragraphs 4 (a) - (f) below), the Company will
compensate the Executive as follows:


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                            (a)    Continue to pay the Annual Base Salary and
                                   provide the welfare benefits under Paragraph
                                   2(d) for one year or until the end of the
                                   Term, whichever occurs sooner;

                            (b)    Pay any earned but unpaid bonus for a prior
                                   calendar year plus a pro rata bonus equal to
                                   (i) the bonus amount earned under Paragraph
                                   2(b) for the calendar year before the year in
                                   which the termination without Cause occurs
                                   (or, if the termination occurs before January
                                   1, 2001, the Annual Base Salary), multiplied
                                   by (ii) a fraction, the numerator of which is
                                   the number of days in the calendar year
                                   through the date of termination without Cause
                                   and the denominator of which is 365.

                            (c)    Accelerate vesting of all of the Executive's
                                   outstanding options, including options not
                                   granted pursuant to Paragraph 2(c) of this
                                   Agreement, which are unvested as of the date
                                   of termination without Cause.

              4.     TERMINATION FOR CAUSE

              Executive's employment may be terminated for "Cause" by the
Company upon thirty (30) days written notice, provided that the Executive shall
have the opportunity to cure the events constituting Cause during such thirty
(30) day notice period. If the Cause has not been cured by the Executive at the
end of the thirty (30) day notice period, Executive's Annual Base Salary,
benefits and vesting of all options shall cease as of the conclusion of the
thirty day notice period of termination for Cause. At the conclusion of the
thirty (30) day notice period, a special session of the full Board of Directors,
excluding Executive, will be convened to consider the alleged conduct or events
constituting "Cause." In the event the Board of Directors, after considering the
alleged conduct or events and rebuttal by the Executive, vote with a 2/3
majority of all the directors of the Board, excluding Executive, that "Cause"
exists under the terms of this Agreement, the Executive's termination for
"Cause" will be confirmed. However, if less than a 2/3 majority votes for
"Cause", Executive's Annual Base Salary, benefits and vesting of all options
shall recommence as of the date they ceased. "CAUSE" is defined as any one of
the following:

                     (a) Executive's substantial failure to perform the material
                         duties under the Agreement;

                     (b) Willful or gross neglect of assigned duties so as to
                         cause material harm to the Company;

                     (c) Willful misconduct or gross negligence that materially
                         and adversely impacts the reputation of the Company; or

                     (d) Executive's material breach of any provision of this
                         Agreement.


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              In addition, the Executive may, at the Company's option, be
terminated without notice and for "Cause" if any one of the following events
occur:

                     (e) Conviction of a felony or a crime involving moral
                         turpitude; or

                     (f) Material fraud or personal dishonesty involving Company
                         assets.

              If the Executive is terminated for Cause, Executive's Annual Base
Salary, benefits, and vesting of all options shall cease as of the date of the
Executive's termination for Cause, and the Executive shall not receive any
severance pay or other benefits following such termination except as required by
applicable law; provided, however, that the Executive shall receive any portion
of the Annual Base Salary and bonus earned but unpaid as of the date of such
termination for Cause.

              5.     TERMINATION WITHOUT GOOD REASON

              If Executive terminates his employment with the Company without
"Good Reason" (as defined below in Paragraph 6) prior to the expiration of the
Term, Executive's Annual Base Salary, benefits, and vesting of all options shall
cease as of the date of the Executive's termination without Good Reason, the
Executive shall voluntarily resign from the Company's Board of Directors and
Executive Committee, and the Executive shall not receive any severance pay or
other benefits following such termination except as required by applicable law;
provided, however, that the Executive shall receive any portion of the Annual
Base Salary and bonus earned but unpaid as of the date of such termination
without Good Reason.

              6.     TERMINATION WITH GOOD REASON

                     If Executive terminates his employment with the Company
with "Good Reason" prior to the expiration of the Term, the Company will
compensate the Executive as follows:

                            (a)    Continue to pay the Annual Base Salary and
                                   provide the welfare benefits under Paragraph
                                   2(d) for one year or until the end of the
                                   Term, whichever occurs sooner;

                            (b)    Pay any earned but unpaid bonus for a prior
                                   calendar year plus a pro rata bonus equal to
                                   (i) the bonus amount earned under Paragraph
                                   2(b) for the calendar year before the year in
                                   which the termination with Good Reason occurs
                                   (or, if the termination occurs before January
                                   1, 2001, the Annual Base Salary), multiplied
                                   by (ii) a fraction, the numerator of which is
                                   the number of days in the calendar year
                                   through the date of termination with Good
                                   Reason and the denominator of which is 365;
                                   and

                            (c)    Accelerate vesting of all of the Executive's
                                   outstanding options, including options not
                                   granted pursuant to Paragraph 2(c) of this
                                   Agreement, which are unvested as of the date
                                   of termination with Good Reason.


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"GOOD REASON" is defined as any one of the following:

              (i)    Company's material breach of any provision of this
                     Agreement;

              (ii)   Any material adverse change in Executive's position
                     (including status, offices, titles and reporting
                     requirements), authority, duties or responsibilities, or
                     any other action by the Company or the Board of Directors
                     which results in: (A) a diminution in any material respect
                     in the Executive's position, authority, duties,
                     responsibilities or compensation; or (B) a material
                     diversion from the Executive's performance of the functions
                     of his position, excluding for this purpose material
                     adverse changes made with the Executive's written consent
                     or due to Executive's termination for Cause or termination
                     without Good Reason;

              (iii)  Involuntary relocation of the Executive's regular work
                     address to a location which requires Executive to travel
                     more than fifty (50) miles from his residence;

provided, however, that it shall not constitute Good Reason unless Executive has
given the Company written notice of its alleged actions constituting Good Reason
and the Company has not cured any such alleged Good Reason within thirty (30)
days of the Company's receipt of such written notice. For purposes of clause
(ii), a material diminution of title, position, duties or responsibilities shall
be deemed to occur if the Company becomes a subsidiary of another corporation
unless, immediately after the Company becomes a subsidiary, persons who hold a
majority of the outstanding voting securities entitled to vote generally in the
election of directors of the parent company are persons who, immediately prior
to the Company becoming a subsidiary, held the Company Voting Stock (as defined
in Paragraph 9 below) and the Executive remains as Chief Executive Officer (with
the same duties as set forth above in Paragraph 1) of the public entity.

              7.     POST-TERMINATION ACTIVITIES

                     (a)    The Executive agrees that during his employment with
the Company and for 12 months thereafter, the Executive will not, and will not
cause others to:

                            (i)    solicit or induce or attempt to solicit or
       induce any employee or full time consultant of the Company (whether such
       person is presently employed by the Company or may later be employed), to
       leave the Company's employ or otherwise interfere with the employment
       relationship between any such person and the Company;

                            (ii)   solicit for competitive purposes, or attempt
       to divert, take away, any exclusive suppliers or customers of the Company
       or potential customers of the Company to whom the Company has made
       presentations seeking to establish business relationships during the
       Term, of which the Executive knew or should have known; or

                            (iii)  publicly disparage the Company, its
       operations, business, Board, directors, officers, management or
       employees; or


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                            (iv)   compete with the Company or its subsidiaries
       in the ASP market anywhere in the United States; provided, however, that
       this clause (iv) shall not apply upon the Executive's termination by the
       Company without Cause or termination by the Executive for Good Reason.

                     (b)    In the event the terms of this Paragraph 7 shall be
determined by any court of competent jurisdiction to be unenforceable by reason
of its time period or geographic scope, the terms will be interpreted to extend
only over the maximum period of time and geographic scope which the court
determines are enforceable.

              8.     NONDISCLOSURE OF CONFIDENTIAL INFORMATION

                     The Executive shall not improperly disclose any
confidential information or trade secrets of the Company during the course of
his employment and in perpetuity thereafter.

              9.     CHANGE IN CONTROL

              If during the Term, and while the Executive is still employed, a
"Change in Control" (as defined below) occurs, then all of the Executive's
options then outstanding shall vest immediately before the Change in Control. A
"CHANGE IN CONTROL" is defined as:

              (i)    the acquisition by any Person, as defined in this Paragraph
9, in a single transaction or a series of transactions (other than through the
distribution of shares of the securities of the Company from the Company's
Series A or B venture investors pursuant to partnership or distribution
agreements) of the beneficial ownership (within the meaning of Rule 13d-3
promulgated under the Securities Exchange Act of 1934, as amended) of 50% or
more of (A) the then outstanding shares of the securities of the Company, or (B)
the combined voting power of the then outstanding securities of the Company
entitled to vote generally in the election of directors (the "Company Voting
Stock");

              (ii)   the closing of a sale or other conveyance of all or
              substantially all of the assets of the Company; or

              (iii)  the effective time of any merger, share exchange,
              consolidation, or other business combination of the Company if
              immediately after such transaction persons who hold a majority of
              the outstanding voting securities entitled to vote generally in
              the election of directors of the surviving entity (or the entity
              owning 100% of such surviving entity) are not persons who,
              immediately prior to such transaction, held the Company Voting
              Stock.

              For purposes of this Paragraph 9, a "Person" means any individual,
entity or group within the meaning of Section 13(d)(3) or 14(d)(2) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), other than:
employee benefit plans sponsored or maintained by the Company or entities
controlled by the Company.


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              10.    EXCISE TAX ON PARACHUTE PAYMENTS


              The Executive shall bear all expense of, and be solely responsible
for, all federal, state, local or foreign taxes due with respect to any payment
received hereunder, including, without limitation, any excise tax imposed by
Section 4999 of the Internal Revenue Code of 1986, as amended (the "Code");
provided, however, that any payment or benefit received or to be received by the
Executive in connection with a Change in Control or the termination of the
Executive's employment (whether payable pursuant to the terms of this Agreement
("Contract Payments") or any other plan, arrangements or agreement with the
Company or any affiliate (collectively with the Contract Payments, the "Total
Payments") shall be reduced to the extent necessary so that no portion thereof
shall be subject to the excise tax imposed by Section 4999 of the Code but only
if, by reason of such reduction, the net after-tax benefit received by the
Executive shall exceed the net after-tax benefit received by the Executive if no
such reduction was made. For purposes of this Paragraph 10, "net after-tax
benefit" shall mean (i) the total of all payments and the value of all benefits
which the Executive receives or is then entitled to receive from the Company
that would constitute "parachute payments" within the meaning of Section 280G of
the Code, less (ii) the amount of all federal, state and local income taxes
payable with respect to the foregoing calculated at the maximum marginal income
tax rate for each year in which the foregoing shall be paid to the Executive
(based on the rate in effect for such year as set forth in the Code as in effect
at the time of the first payment of the foregoing), less (iii) the amount of
excise taxes imposed with respect to the payments and benefits described in (i)
above by Section 4999 of the Code. The foregoing determination shall be made by
a nationally recognized accounting firm (the "Accounting Firm") selected by the
Company and reasonably acceptable to the Executive (which may be, but will not
be required to be, the Company's independent auditors). The Accounting Firm
shall submit its determination and detailed supporting calculations to both the
Executive and the Company within fifteen (15) days after receipt of a notice
from either the Company or the Executive that the Executive may receive payments
which may be "parachute payments." If the Accounting Firm determines that such
reduction is required by this Paragraph 10, the Executive, in the Executive's
sole and absolute discretion, may determine which Total Payments shall be
reduced to the extent necessary so that no portion thereof shall be subject to
the excise tax imposed by Section 4999 of the Code, and the Company shall pay
such reduced amount to the Executive. If the Accounting Firm determines that no
reduction is necessary under this Paragraph 10, it will, at the same time as it
makes such determination, furnish the Executive and the Company an opinion that
Executive shall not be liable for any excise tax under Section 4999 of the Code.
The Executive and the Company shall each provide the Accounting Firm access to
and copies of any books, records, and documents in the possession of the
Executive or the Company, as the case may be, reasonably requested by the
Accounting Firm, and otherwise cooperate with the Accounting Firm in connection
with the preparation and issuance of the determinations and calculations
contemplated by this Paragraph 10. The fees and expenses of the Accounting Firm
for its services in connection with the determinations and calculations
contemplated by this Paragraph 10 shall be borne by the Company.


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              11.    RESTRICTION ON STOCK

                     For a period of one (1) year from the Effective Date, the
Executive agrees not to make any dispositions or sales of any common stock of
the Company that would be reportable as "non-exempt dispositions" under Section
16(b) of the Exchange Act. Notwithstanding the foregoing sentence, the Company
agrees that the Executive may transfer common stock of the Company

              (i) to one or more charities, charitable remainder trusts or
charitable annuity trusts,

              (ii) to immediate family members, related by blood, marital
relations or adoption, or to one or more family trusts for the benefit of such
immediate family members, without limitation as to number of shares; provided
that the transferee under this clause (ii) agrees not to transfer or sell such
shares within the one (1) year period commencing on the Effective Date,

              (iii) up to an aggregate of 450 shares to immediate family members
without restriction on such family members' right to subsequently sell or
transfer the shares, and

              (iv) up to 5% of Executive's then current unrestricted holdings of
the Company's common stock in any secondary public offering of the Company's
common stock.

The restrictions imposed under this Paragraph 11 shall not apply after the
Executive's employment with the Company is terminated: (A) by the Executive with
Good Reason; (B) by the Company with or without Cause; or (C) on account of the
Executive's death or Disability.

              12.    LEGAL FEES

                     The Company agrees to reimburse the Executive for all legal
and professional fees and costs incurred by the Executive in connection with the
negotiation and preparation of this Agreement and the Non-Qualified Stock Option
Agreements referred to in Paragraph 2 of this Agreement, but in no event to
exceed $10,000.

              13.    BURDEN AND BENEFIT

                     This Agreement shall be binding upon, and shall inure to
the benefit of, the Company and the Executive, and their respective heirs,
personal and legal representatives, successors and assigns. This Agreement may
not be assigned by the Executive without the prior written consent of the
Company.

              14.    SEVERABILITY

                     The provisions of this Agreement shall be deemed severable,
and the invalidity or unenforceability of any one or more of the provisions
hereof shall not affect the validity or enforceability of the other provisions
of this Agreement.


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              15.    ENTIRE AGREEMENT

                     This Agreement contains the entire agreement and
understanding by and between the Company and the Executive with respect to the
subject matter hereof, and no representations, promises, agreements or
understandings, written or oral, not contained herein shall be of any force or
effect. No change or modification hereof shall be valid or binding unless the
same is in writing and signed by the party against whom such waiver is sought to
be enforced; moreover, no valid waiver of any provision of this Agreement at any
time shall be deemed a waiver of any other provision of this Agreement at such
time or will be deemed a valid waiver of such provision at any other time.

              16.    GOVERNING LAW

                     This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Maryland.

              17.    ARBITRATION

                     Any dispute or controversy arising under or in connection
with this Agreement which is not settled to the satisfaction of either party
pursuant to the special Board session set forth above in Paragraph 4 or
otherwise shall be settled exclusively by arbitration, conducted before a single
arbitrator in Baltimore, MD in accordance with the rules of the JAMS/ENDISPUTE
then in effect. Judgment may be entered on the arbitrator's award in any court
having jurisdiction; provided, however, that the Company shall be entitled to
seek a restraining order or injunction in any court of competent jurisdiction to
prevent any continuation of any violation of the provisions of Sections 7 or 8
of the Agreement and the Executive hereby consents that such restraining order
or injunction may be granted without the necessity of the Company's posting any
bond. The fees and expense of the arbitrator shall be borne by the
non-prevailing party.

              18.    NOTICES

                     Any notice under this Agreement shall be in writing and
delivered by fax, e-mail or registered mail to the signatories at the addresses
below.

              IN WITNESS WHEREOF, the parties have executed this Agreement on
the date and year first above written.

ANDREW A. STERN:                      USINTERNETWORKING, INC.

/s/ ANDREW A. STERN                   By: /s/ FRANK A. ADAMS
-----------------------------            ---------------------------------------
Address:                                 Frank A. Adams
                                         Title: Chairman, Compensation Committee
                                         ONE USi PLAZA, ANNAPOLIS, MD 21401-7478


WITNESS: /s/ WILLIAM T. PRICE
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