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                                                                   EXHIBIT 10.15

                              EMPLOYMENT AGREEMENT

      This EMPLOYMENT AGREEMENT, dated as of November 13, 2000 (hereinafter
"Agreement"), by and between PSINet Inc. (hereinafter "the Company"), a New York
corporation with its principal place of business located at 44983 Knoll Square,
Ashburn, Virginia 20147 and Lota S. Zoth (hereinafter "the Executive").

      WHEREAS, the Company has determined that it is in the best interests of
the Company to delegate certain management responsibilities of the Company to
the Executive;

      WHEREAS, the Executive is willing to provide her services as an
employee of the Company for the inducements and on the terms and conditions set
forth below in this Agreement; and

      NOW, THEREFORE, in consideration of the mutual covenants set forth
herein and other good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, the parties hereto agree as follows:

      1. EMPLOYMENT POSITION.

         (a) POSITION AND DUTIES. The Company hereby employs the Executive to
         serve as Senior Vice President, Corporate Controller of the Company and
         the Executive hereby accepts such retention in the capacity and subject
         to the terms and conditions hereinafter set forth. This position is a
         corporate officer position and, as an officer of the Company, the
         Executive must stand for election by the Company's Board of Directors
         (the "Board") each year of the Term (as defined in Section 2 hereof).
         The Executive shall have such powers, duties, authority, and
         responsibilities as are (i) consistent with such position, (ii)
         assigned to such offices in the Company's By-laws, and (iii) reasonably
         assigned to the Executive by the Chief Financial OFFICER. The Executive
         accepts such employment and agrees to remain in the employ of the
         Company and provide management services to the Company, as determined
         by and under the direction of the Chief Financial Officer.

         (b) LOCATION OF EMPLOYMENT. The principal place of employment of the
         Executive shall be in the greater Washington, D.C. area. Executive
         shall be available to travel to the extent reasonably required to carry
         out the duties and responsibilities as Senior Vice President, Corporate
         Controller or as otherwise may be reasonably required by the business
         of the Company.

         (c) MANAGEMENT RESPONSIBILITIES. The Executive shall at all times
         perform his or her responsibilities and duties with appropriate care
         and consistent with his position as may be assigned by the Chief
         Financial Officer and shall at all times exercise reasonable judgment
         and discretion in the performance of such responsibilities and duties.

      2. TERM OF EMPLOYMENT. The initial term of the Executive's employment
under this Agreement shall commence as of the date of this Agreement and shall
terminate on the second anniversary hereof (the "Initial Term") subject to
earlier termination as provided in Section 6.


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Thereafter, this Agreement shall be automatically extended each year for an
additional one (1) year period (each, a "Renewal Term"). The Initial Term
together with any Renewal Term are referred to herein collectively as the
"Term."

      3. COMPENSATION.

         (a) BASE SALARY. The Company shall pay the Executive a base salary at a
         rate of $195,000.00 per year beginning on the date hereof. Beginning on
         January 1, 2001 and January 1 of each subsequent year thereafter, the
         Executive's base salary shall be increased at a minimum by an amount
         equal to five percent (5%) of the Executive's then current base salary.
         The Executive's base salary shall be subject to additional increases at
         the discretion of the Chief Financial Officer subject to the approval
         of the Compensation Committee of the Board (the "Compensation
         Committee"). The Executive's base salary shall be payable in such
         installments as the Company regularly pays its other salaried
         employees. All payments shall be subject to the deduction of payroll
         withholdings taxes and similar assessments as required by law or by
         further agreement with the Executive.

         (b) PERFORMANCE BONUS. The Company will pay the Executive a bonus
         subject to the successful completion of the objectives established for
         the Executive's performance for each calendar year during the Term. The
         performance criteria will be issued separately by the Chief Financial
         Officer with respect to each calendar year during the Term, and may be
         changed, with mutual fairness, from time to time as situations develop.
         The target bonus for the period ending December 31, 2000, will be a
         total of up to $65,000.00. Separate criteria will be established for
         the Executive's entitlement for the year starting January 1, 2001.
         Bonuses in subsequent years during the Term will be at least equal to
         the amount of the bonus during the previous calendar year.

         (c) STOCK OPTIONS. On the first anniversary of the date of this
         Agreement and each subsequent anniversary date during the Term, the
         Company shall grant the Executive options to purchase 15,000 shares of
         the Company's common stock (the "Options") pursuant to the Company's
         Executive Stock Incentive Plan (the "Plan") or another option plan of
         the Company, such grant being subject to the terms of this Agreement
         and the Executive's continued employment at the time of the grant and
         evidenced by an option agreement in such form and under the terms and
         conditions set forth in the applicable plan.

         (d) VESTING OF STOCK OPTIONS. In the event of a Change in Control (as
         defined in Section 3(e) hereof), the Company shall immediately vest all
         of the unvested stock options the Executive has received prior to the
         date of the Change in Control.

         (e) CHANGE IN CONTROL. As used in this Agreement, "Change in Control"
         shall mean: (i) the shareholders of the Company approve an agreement
         for the sale of all or substantially all of the assets of the Company;
         or (ii) the shareholders of the Company approve a merger or
         consolidation of the Company with any other corporation (and the
         Company implements it), other than (A) a merger or consolidation which
         would result in the voting securities of the Company outstanding
         immediately prior thereto continuing to represent more

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         than eighty percent (80%) of the combined voting power of the voting
         securities of the Company, or such surviving entity, outstanding
         immediately after such merger or consolidation, or (B) a merger or
         consolidation effected to implement a recapitalization of the Company
         (or similar transaction) in which no "person" (as defined below)
         acquires more than thirty percent (30%) of the combined voting power of
         the Company's then-outstanding securities; or (iii) any "person," as
         such term is used in Sections 13(d) and 14(d) of the Securities
         Exchange Act of 1934, as amended (the "Exchange Act") (other than (1)
         the Company or (2) any corporation owned, directly or indirectly, by
         the Company or the shareholders of the Company in substantially the
         same proportions as their ownership of stock in the Company), is or
         becomes the "beneficial owner" (as defined in Rule 13d-3 under the
         Exchange Act), directly or indirectly, of securities of the Company
         representing thirty percent (30%) or more of the combined voting power
         of the Company's then outstanding securities.

      4. FRINGE BENEFITS; AUTOMOBILE ALLOWANCE.

         (a) During the Term, the Executive shall be entitled to the maximum
         benefits that are generally provided to all senior executives of the
         Company under any life insurance, group insurance, medical, retirement,
         pension or other employee benefit or incentive plans or pursuant to
         other arrangements or understandings (excluding any equity, equity
         option or equity bonus plans), so long as any such plan, benefit,
         arrangement or understanding remains generally available to all other
         senior executive officers of the Company.

         (b) During the Term, the Executive shall also receive an automobile
         allowance of $800 per month or whatever greater amount the Company pays
         to its Executives as a matter of standard practice from time to time.

         (c) During the Term, the Executive shall be entitled to financial and
         tax advice at the Company's expense through the Mason Companies up to a
         maximum amount of $7,000.00 per year.

         (d) During the Term, the Executive shall be entitled to four (4) weeks
         paid vacation each year which can accumulate to a maximum of six (6)
         weeks.

      5. EXPENSE REIMBURSEMENT. In addition to the compensation and benefits
provided in Sections 3 and 4, the Company shall, upon receipt of appropriate
documentation, reimburse the Executive for his reasonable travel, lodging,
entertainment, and other ordinary and necessary business expenses incurred in
the course of his duties on behalf of the Company during the Term.

      6. TERMINATION.  The Term is subject to early termination as provided
below:

         (a) TERMINATION BY REASON OF DISABILITY. If at any time during the
         Term, the Company determines in good faith that the Executive has been
         unable, as a result of physical or mental illness or incapacity, to
         perform his duties hereunder for a period of either (i) one hundred
         eighty (180) consecutive days during any twelve-month period or (ii)
         ninety (90) consecutive days during any twelve-month period if the
         Executive's physical or mental illness or incapacity would reasonably
         be expected to continue for another consecutive ninety (90) day period
         after such initial ninety (90) day period, the Term may be terminated
         by


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         the Company upon thirty (30) days' written notice to the Executive.
         Should termination occur pursuant to this Section 6(a), the Executive
         shall be entitled to receive disability benefits consistent with the
         Company's policy.

         (b) TERMINATION BY THE COMPANY BECAUSE OF THE EXECUTIVE'S DEATH. In the
         event that the Executive's death occurs prior to the expiration of the
         Term, the Term shall terminate as of the date of the Executive's death.
         In the event of a termination under Section 6(b), all salary and
         benefits otherwise payable to the Executive under this Agreement shall
         cease immediately.

         (c) TERMINATION BY THE COMPANY FOR CAUSE. The Executive's employment
         may be terminated by the Company at any time for "Cause." In the event
         of a termination for Cause, all salary and benefits otherwise payable
         to the Executive shall cease immediately upon such termination. For
         purposes of this Agreement, the Company shall have Cause for
         termination of the Executive's employment under this Agreement by
         reason of (i) any breach by the Executive of his agreement not to
         compete or solicit pursuant to Section 7 hereof; (ii) any violation of
         Company policy which materially and adversely affects the business or
         reputation of the Company; (iii) any act or omission by the Executive
         constituting willful misconduct or gross negligence, (iv) the
         Executive's conviction of a felony (or a plea of guilty or NOLO
         CONTENDRE thereto); (v) the Executive's conviction of any other
         criminal action (or a plea of guilty or NOLO CONTENDRE thereto) that
         has or might reasonably be expected to have an adverse effect on the
         business or reputation of the Company or its subsidiaries; (vi) the
         Executive's commission of an act of fraud; (vii) a material breach by
         the Executive of any provision of this Agreement which breach and the
         effects thereof remain uncured for a period of thirty (30) days after
         written notice, specifically identifying the breach, is given to the
         Executive by the Company (however, it being expressly understood that
         the Company need not provide any notice and may terminate the Executive
         immediately where the Company in good faith believes that the
         Executive's material breach is not curable within thirty (30) days); or
         (viii) the Executive's voluntary resignation without having given the
         Company at least thirty (30) days prior written notice.

         (d) TERMINATION BY THE COMPANY WITHOUT CAUSE. The Company may terminate
         the employment of the Executive under this Agreement at any time
         without cause with thirty (30) days' prior written notice. Should the
         Executive be terminated pursuant to this Section 6(d), he shall be
         entitled to Termination Payments as provided for in Section 6(f).

         (e) EXECUTIVE'S RIGHT TO TERMINATION. The Executive may terminate his
         employment at any time, provided that the Executive shall have given
         the Company at least thirty (30) days prior written notice of such
         termination. In the event of termination by the Executive, the
         Executive's salary and benefits shall continue during the notice period
         specified by the Executive and shall cease thereafter.

         (f) TERMINATION PAYMENTS. A. If the Executive's employment is
         terminated by the Company without Cause pursuant to Section 6(d)
         (hereinafter the "Termination Event"), the Company shall provide the
         Executive the following


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         (collectively, the "Termination Payments"), to be paid or given within
         thirty (30) days of the Date of Termination:

                  (i)      a lump sum representing (1) the Executive's monthly
                           base salary as derived from the Executive's annual
                           salary and giving effect to all annual increases
                           thereto as provided in Section 3(a) herein, times the
                           greater of (y) the number of months remaining in the
                           current Term or (z) twelve (12) months; and (2) all
                           other accrued and unpaid amounts due to the Executive
                           as of the Date of Termination (including, without
                           limitation, accrued vacation pay and reimbursement of
                           business expenses);

                  (ii)     a lump sum representing all annual bonus amounts, as
                           provided for in Section 3(b) hereof, calculated on
                           the assumption that all performance criteria
                           objectives would have been exceeded, such that the
                           Executive would receive the maximum bonus established
                           by the Chief Financial Officer to which the Executive
                           would have been entitled had he remained employed by
                           the Company for the longer of (y) the remainder of
                           the current Term or (z) twelve (12) months after the
                           Date of Termination.

                  B. If the Termination Event occurs within twelve months after
         a Change in Control, the Executive is entitled to the Termination
         Payments as stated in Section 6(f)(A)(i) and (ii) above as well as the
         following:

                  (iii)    continuation of all life insurance and health
                           benefits, disability insurance and benefits and
                           reimbursement theretofore being provided to the
                           Executive and/or his family, or such other more
                           favorable benefits applicable to any senior executive
                           officer of the Company, to which the Executive would
                           have been entitled had he remained employed by the
                           Company for the longer of (y) the remainder of the
                           current Term or (z) twelve (12) months after the Date
                           of Termination, with the exception of the car
                           allowance as provided in Section 4(b) herein;

                  (iv)     Company contributions, to the extent permitted by
                           applicable law, to a SEP-IRA, Keogh or other
                           retirement mechanism reasonably selected by the
                           Executive sufficient to provide the same level of
                           retirement benefits the Executive would have received
                           if he had remained employed by the Company for the
                           longer of (y) the remainder of the current Term or
                           (z) twelve (12) months after the Date of Termination,
                           provided, however, that the Company shall make up the
                           difference in cash payments directly to the Executive
                           to the extent that applicable law would not permit it
                           to make such contributions.

                  C. In consideration of the Termination Payments provided in
         this Section 6(f)(A) and (B), the Executive agrees to execute a
         termination of employment agreement under which the Executive agrees to
         fully release all claims against the Company.


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         (g) NOTICE OF TERMINATION. Any termination of the Executive's
         employment during the Term by the Company or by the Executive shall be
         communicated by Notice of Termination to the other party hereto given
         in accordance with Section 16 of this Agreement. For purposes of this
         Agreement, a "Notice of Termination" means a written notice which (i)
         indicates the specific termination provision in this Agreement relied
         upon, (ii) to the extent applicable, sets forth in reasonable detail
         the facts and circumstances claimed to provide a basis for termination
         of the Executive's employment under the provision so indicated, and
         (iii) if applicable, specifies a termination date. The failure by the
         Executive or the Company to set forth in the Notice of Termination any
         fact or circumstance which contributes to a showing of Good Reason or
         Cause shall not waive any right of the Executive or the Company
         hereunder or preclude the Executive or the Company, as applicable, from
         asserting such fact or circumstance in enforcing the Executive's or the
         Company's rights hereunder.

         (h) DATE OF TERMINATION. For purposes of this Agreement, "Date of
         Termination" means (i) if the Executive's employment is terminated by
         reason of death, the date of death; or (ii) if the Executive's
         employment is terminated under any other circumstances, the date of
         receipt of the Notice of Termination by the party being so notified or
         any later date specified therein. For purposes of this Agreement, the
         Executive will be deemed to be employed through the end of the calendar
         day on the Date of Termination.

         (i) TAX PROVISIONS. In the event that any payments under this Agreement
         or any other compensation, benefit or other amount from the Company for
         the benefit of the Executive are subject to the tax imposed by Section
         4999 of the Internal Revenue Code of 1986, as amended (the "Code")
         (including any applicable interest and penalties, the "Excise Tax"), no
         such payment ("Parachute Payment") shall be reduced (except for
         required tax withholdings) and the Company shall pay to the Executive
         by the earlier of the date such Excise Tax is withheld from payments
         made to the Executive or the date such Excise Tax becomes due and
         payable by the Executive, an additional amount (the "Gross-Up Payment")
         such that the net amount retained by the Executive (after deduction of
         any Excise Tax on the Parachute Payments, taxes based upon the Tax Rate
         (as defined below) upon the payment provided for by this Section 6(i)
         and Excise Tax upon the payment provided for by this Section 6(i)),
         shall be equal to the amount the Executive would have received if no
         Excise Tax had been imposed. A Tax counsel chosen by the Company's
         independent auditors, provided such person is reasonably acceptable to
         the Executive ("Tax Counsel"), shall determine in good faith whether
         any of the Parachute Payments are subject to the Excise Tax and the
         amount of any Excise Tax, and Tax Counsel shall promptly notify the
         Executive of its determination. The Company and the Executive shall
         file all tax returns and reports regarding such Parachute Payments in a
         manner consistent with the Company's reasonable good faith
         determination. For purposes of determining the amount of the Gross-Up
         Payment, the Executive shall be deemed to pay taxes at the Tax Rate
         applicable at the time of the Gross-Up Payment. In the event that the
         Excise Tax is subsequently determined to be less than the amount taken
         into account hereunder at the time a Parachute Payment is made, the
         Executive shall repay to the Company promptly following the date that
         the amount of such reduction in Excise Tax is finally determined the

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         portion of the Gross-Up Payment attributable to such reduction (without
         interest). In the event that the Excise Tax is determined to exceed the
         amount taken into account hereunder at the time a Parachute Payment is
         made (including by reason of any payment the existence or amount of
         which cannot be determined at the time of the Gross-Up Payment), the
         Company shall pay the Executive an additional amount with respect to
         the Gross-Up Payment in respect of such excess (plus any interest or
         penalties payable in respect of such excess) at the time that the
         amount of such excess is finally determined. The Company shall
         reimburse the Executive for all reasonable fees, expenses, and costs
         related to determining the reasonableness of any Company position in
         connection with this paragraph and preparation of any tax return or
         other filing that is affected by any matter addressed in this
         paragraph, and any audit, litigation or other proceeding that is
         affected by any matter addressed in this Section 6(i) and an amount
         equal to the tax on such amounts at the Executive's Tax Rate. For the
         purposes of the foregoing, "Tax Rate" means the Executive's effective
         tax rate based upon the combined federal and state and local income,
         earnings, Medicare and any other tax rates applicable to the Executive,
         all at the highest marginal rate of taxation in the country and state
         of the Executive's residence on the date of determination, net of the
         reduction in federal income taxes which could be obtained by deduction
         of such state and local taxes.

      7. COVENANTS OF EXECUTIVE

         (a) COVENANT NOT TO COMPETE. In consideration of the Executive's
         employment pursuant to this Agreement and for other good and valuable
         consideration, the receipt and adequacy of which is hereby
         acknowledged, the Executive agrees that, so long as the Executive is
         employed by the Company under this Agreement and for a period of twelve
         (12) months following the termination of such employment (but only if
         the Company has elected to enforce the restriction), the Executive
         shall not, without the prior written consent of the Company, either for
         the Executive or for any other person, firm or corporation, own,
         manage, operate, control, be employed by, participate in or be
         associated in any manner with the ownership, management, operation or
         control of any business providing Internet-related, E-commerce,
         web-hosting, network or communication services competitive with the
         Company as of the Date of Termination or within six (6) months
         thereafter. The foregoing shall in no event restrict the Executive
         from: (i) writing or teaching, whether on behalf of for-profit, or
         not-for-profit institution(s); (ii) investing (without participating in
         management or operation) in the securities of any private or publicly
         traded corporation or entity; or (iii) after termination of employment,
         becoming employed by a hardware, software or other vendor to the
         Company, provided that such vendor does not offer Internet-related,
         E-commerce, or web-hosting network or communication services that are
         competitive with the services offered by the Company as of the Date of
         Termination or within six (6) months thereafter.

         (b) NONSOLICITATION. In consideration of the Executive's employment
         pursuant to this Agreement and for other good and valuable
         consideration, the receipt and adequacy of which is hereby
         acknowledged, the Executive agrees that, so long as the Executive is
         employed by the Company under this Agreement and for a period of
         eighteen (18) months following the termination of such


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         employment, the Executive agrees not to hire, solicit, nor attempt to
         solicit for himself or any third party, the services of any employee or
         subcontractor of the Company or any of the Company's subsidiaries or
         affiliates without the Company's prior written consent; provided,
         however, that the Executive is not prevented from employing such person
         who contacts the Executive on his or her own initiative and without any
         direct or indirect solicitation by the Executive.

         (c) BREACH/THREATENED BREACH. The Executive may request permission from
         the Company's Board of Director's to engage in activities which would
         otherwise be prohibited by Section 7(a) or (b). The Company shall
         respond to such request within thirty (30) days after receipt. The
         Company shall notify the Executive in writing if it becomes aware of
         any breach or threatened breach of any of the provisions in Section
         7(a) or (b), and the Executive shall have thirty (30) days after
         receipt of such notice in which to cure or prevent the breach, to the
         extent that the Executive is able to do so. The Executive and the
         Company acknowledge that any breach or threatened breach by the
         Executive of any of the provisions in Section 7(a) or (b) above cannot
         be remedied by the recovery of damages, and agree that in the event of
         any such breach or threatened breach which is not cured with such
         30-day period, the Company may pursue injunctive relief for any such
         breach or threatened breach. If a court of competent jurisdiction
         determines that the Executive breached any of such provisions, the
         Executive shall not be entitled to any Termination Payments from and
         after date of the breach. In such event, the Executive shall promptly
         repay any Termination Payments previously made plus interest thereon
         from the date of such payment(s) at 12% per annum. If, however, the
         Company has suspended making such Termination Payments and a court of
         competent jurisdiction finally determines that the Executive did not
         breach such provision or determines such provision to be unenforceable
         as applied to the Executive's conduct, the Executive shall be entitled
         to receive any suspended Termination Payment, plus interest thereon
         from the date when due at 12% per annum. The Company may elect (once)
         to continue paying the Termination Payments before a final decision has
         been made by the court.

         (d) OWNERSHIP OF WORK PRODUCT. All copyrights, patents, trade secrets,
         or other intellectual property rights associated with any ideas,
         concepts, techniques, inventions, processes, or works of authorship
         developed or created by the Executive during the course of performing
         the Company's work (collectively the "Work Product") shall belong
         exclusively to the Company and shall, to the extent possible, be
         considered a work made for hire for the Company within the meaning of
         Title 17 of the United States Code. The Executive automatically
         assigns, and shall assign at the time of creation of the Work Product,
         without any requirement of further consideration, any right, title, or
         interest the Executive may have in such Work Product, including any
         copyrights or other intellectual property rights pertaining thereto.
         Upon request of the Company, the Executive shall take such further
         actions, including execution and delivery of instruments of conveyance,
         as may be appropriate to give full and proper effect to such
         assignment.

         (e) EQUITABLE RELIEF. The Executive acknowledges and agrees that the
         covenants and obligations of Executive contained in Section 7 hereof
         relate to special, unique and extraordinary matters and are reasonable
         and necessary to


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         protect the legitimate interests of the Company and that a breach of
         any of the terms of such covenants and obligations will cause the
         Company irreparable harm and injury for which adequate remedies at law
         are not available. The Executive therefore agrees that the Company need
         not prove actual damages in order to obtain injunctive relief, a
         restraining order, an order of specific performance or any other
         equitable relief (together, "Equitable Relief") with respect to any of
         Executive's obligations under Section 7. The Executive hereby waives
         any claim or defense therein that the Company has an adequate remedy at
         law or that money damages would provide an adequate remedy. It shall,
         however, be the option of the Company whether or not to seek Equitable
         Relief.

      8. REPRESENTATION AND WARRANTIES.

         (a) THE COMPANY. The Company hereby represents and warrants to the
         Executive as follows:

                  (i)      the Company is duly organized, validly existing and
                           in good standing under the laws of the State of New
                           York;

                  (ii)     this Agreement has been duly authorized, executed and
                           delivered by the Company and will constitute the
                           legal, valid and binding obligation of the Company,
                           enforceable against the Company in accordance with
                           its terms, subject to applicable bankruptcy,
                           insolvency, moratorium or other similar laws
                           affecting the rights of creditors generally and to
                           general principles of equity whether considered in a
                           suit at law or in equity; and

                  (iii)    the execution and delivery of this Agreement by the
                           Company, the performance by the Company of its
                           obligations hereunder and the consummation by the
                           Company of the transactions contemplated hereby will
                           not violate any agreement to which the Company is a
                           party.

         (b) EXECUTIVE. The Executive hereby represents and warrants to the
         Company as follows:

                  (i)      this Agreement has been duly executed and delivered
                           by the Executive and will constitute the legal, valid
                           and binding obligation of the Executive, enforceable
                           against the Executive in accordance with its terms,
                           subject to applicable bankruptcy, insolvency,
                           moratorium or other similar laws affecting the rights
                           of creditors generally and to general principles of
                           equity whether considered in a suit at law or in
                           equity;

                  (ii)     the execution and delivery of this Agreement by
                           Executive, the performance by the Executive of his
                           obligations hereunder and the consummation by the
                           Executive of the transactions contemplated hereby
                           will not violate any agreement to which he is a
                           party; and

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                  (iii)    the Executive has made such investigations of the
                           business and properties of the Company as he deems
                           necessary or appropriate before entering into this
                           Agreement.

      9. TRANSFERABILITY.

         (a) This Agreement is personal to the Executive and without the prior
         written consent of the Company shall not be assignable by the Executive
         otherwise than by will or the laws of descent and distribution. This
         Agreement shall inure to the benefit of and be enforceable by the
         Executive's legal representatives.

         (b) This Agreement shall inure to the benefit of and be binding upon
         the Company, its successors and assigns.

         (c) The Company shall require any successor (whether direct or
         indirect, by purchase, merger, consolidation, share exchange or
         otherwise) to all or substantially all of the business and/or assets of
         the Company to expressly assume in writing and agree to perform this
         Agreement in the same manner and to the same extent that the Company
         would be required to perform it if no such succession had taken place.
         As used in this Agreement, "Company" shall mean the Company as defined
         herein and any successor to its businesses and/or assets as aforesaid
         that assumes and agrees to perform this Agreement by operation of law,
         or otherwise. A failure of the Company to cause a successor to assume
         this Agreement in any such transaction shall be a breach of this
         Agreement by the Company.

      10. NONEXCLUSIVITY OF RIGHTS. Nothing in this Agreement shall prevent
or limit the Executive's continuing or future participation in any benefit,
plan, program, policy or practice provided by the Company and for which the
Executive may qualify (except with respect to any benefit to which the Executive
has waived his rights in writing), nor shall anything herein limit or otherwise
affect such rights as the Executive may have under any other contract or
agreement entered into after the date of this Agreement with the Company.
Amounts which are vested benefits or which the Executive is otherwise entitled
to receive under any benefit, plan, policy, practice or program of, or any
contract or agreement entered into with, the Company shall be payable in
accordance with such benefit, plan, policy, practice or program or contract or
agreement except as explicitly modified by this Agreement.

      11. FULL SETTLEMENT; MITIGATION. In no event shall the Executive be
obligated to seek other employment or take any other action by way of mitigation
of the amounts (including amounts for damages for breach) payable to the
Executive under any of the provisions of this Agreement, and such amounts shall
not be reduced whether or not the Executive obtains other employment. In
addition, in the event of a Change in Control only, the Company's obligation to
make the payments provided for in this Agreement and otherwise to perform its
obligations hereunder shall not be affected by any set-off, counterclaim,
recoupment, defense or other claim, right or action which the Company may have
against the Executive or others.

      12. NO WAIVER. The Executive's or the Company's failure to insist upon
strict compliance with any provision of this Agreement or the failure to assert
any right the Executive or the Company may have hereunder shall not be deemed to
be a waiver of such provision or right or any other provision or right of this
Agreement.

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      13. ARBITRATION. With the exception of disputes arising under Section 7
hereof, any dispute arising under this Agreement shall be settled by arbitration
in accordance with the rules of the American Arbitration Association and
judgment upon the award rendered by the arbitrator may be rendered in any court
having jurisdiction thereof. Arbitration hereunder shall be by a single
arbitrator appointed by agreement of the parties. The parties shall agree that
any arbitration award shall be final and binding on the parties. Except as
stated otherwise in Paragraph 14 of this Agreement, each party shall bear its
own costs and attorneys' fees associated with the arbitration.

      14. COSTS TO THE EXECUTIVE AFTER CHANGE IN CONTROL. Notwithstanding
anything in this Agreement to the contrary, if, following a Change in Control,
any successor in interest to the Company unsuccessfully contests and/or
challenges any of the Executive's rights under this Agreement, then the
successor in interest to the Company shall pay the Executive's reasonable
attorney's fees and costs incurred in such contest or challenge.

      15. SEVERABILITY. The provisions of this Agreement will be deemed
severable, and if any part of any provision is held to be illegal, void,
voidable, invalid, nonbinding, or unenforceable in its entirety or partially or
as to any party, for any reason, such provision may be changed, consistent with
the intent of the parties hereto, to the extent reasonably necessary to make the
provision, as so changed, legal, valid, binding, and enforceable. If any
provision of this Agreement is held to be illegal, void, voidable, invalid,
nonbinding, or unenforceable in its entirety or partially or as to any party,
for any reason, and if such provision cannot be changed consistent with the
intent of the parties hereto to make it fully legal, valid, binding, and
enforceable, then such provision will be stricken from this Agreement, and the
remaining provisions of this Agreement will not in any way be affected or
impaired, but will remain in full force and effect.

      16. ENTIRE AGREEMENT/AMENDMENTS. This Agreement contains and its terms
constitute the entire agreement of the parties and supersedes all prior
agreements regarding the subject matter herein. This Agreement supersedes and
replaces any prior or contemporaneous agreements, negotiations, correspondence,
undertakings and communications of the parties, oral or written. No amendment or
modification of any provision of this Agreement shall be effective unless in
writing and signed by the party against whom enforcement of such amendment or
modification is sought.

      17. NOTICES. All notices required to be given or which may be given
under this Agreement shall be in writing delivered in accordance with one or
more of the following and shall be deemed received upon the earlier of (i) when
it is personally delivered to the party, (ii) three (3) days after having been
mailed by certified mail, postage prepaid, return receipt requested, (iii) two
(2) days after having been sent via overnight delivery by a recognized overnight
delivery service, or (iv) one (1) day after having been sent via facsimile
transmission, in each case addressed to the party intended to be notified at the
address of such party as set forth in the records of the Company or such other
address as such party may designate in writing to the other.

      18. GOVERNING LAW. This Agreement shall be governed by the laws of the
Commonwealth of Virginia without giving effect to the conflicts of law
principles thereof.

      19. SURVIVAL. All provisions which may reasonably be interpreted or
construed to survive the expiration or termination of this Agreement shall
survive the expiration or termination of this Agreement.

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      20. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original and all of which shall
be one and the same instrument.

      21. EXECUTION. This Agreement shall be deemed effective upon the
execution by the Company and the Executive.

      IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed and delivered as the date first written above.


Executive:

/s/ LOTA S. ZOTH
-------------------------
Lota S. Zoth



PSINet Inc. ("Company"):


By: /s/ WILLIAM L. SCHRADER
    --------------------------------
Title: Chairman and Chief Executive Officer















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