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                                                                    EXHIBIT 10.6
                       AMENDMENT TO EMPLOYMENT AGREEMENT


This agreement is dated as of the 1st day of October, 1998, and is an amendment
to the employment agreement between PSINet Inc. (the "Company") and Harry Hobbs
("Hobbs"), dated August 4, 1997.  Except as modified or otherwise provided
herein, all terms and provisions of that employment agreement remain in effect.

This amendment is to provide certain changes in the employment of Hobbs related
to a new assignment in Switzerland as President, Europe for the Company, as well
as a new designation as Senior Vice President of the Company.

1.   Reporting, Responsibility and Term. Hobbs shall continue to report to the
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     Chief Operating Officer of the Company. In his role as President, Europe,
     he shall have operating authority over the Company's European operations
     and responsibility for the results of those operations. His terms as
     President, Europe shall commence as of the date hereof, and extend through
     December 31, 2000, unless earlier terminated or modified by the Company or
     Hobbs in accordance with the other provisions of Hobbs' employment
     agreement.

2.   Base and Bonus Compensation.  Hobbs shall be paid base salary at a rate of
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     $225,000 per year, on the same terms as otherwise provided in the
     employment agreement. In addition, Hobbs shall be eligible for up to
     $112,500 in additional bonus compensation, payable annually, upon
     achievement of stated goals to be mutually agreed with the Chief Operating
     Officer.

3.   Adjustment of Differential Tax Rates. If necessary, the Company shall
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     "gross up" Hobbs' base, bonus and personal travel compensation so that
     Hobbs' after-tax compensation during his tour in Switzerland shall not be
     less than he would have had if stationed in the United States for such
     period and earning the identical compensation. In other words, if the
     combined relative personal tax rate on such compensation is increased by
     reason of Hobbs' location in Switzerland, the Company shall increase the
     compensation such that the after-tax results to Hobbs shall eliminate any
     loss in compensation otherwise caused by the increased tax rate.

4.   Travel to the U.S. The Company shall reimburse Hobbs up to $20,000 (per
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     year) for personal travel expenses between Switzerland and the U.S. This
     reimbursement shall pertain to travel for Hobbs or any member of his
     immediate family (i.e., wife and children).

5.   Automobile. The Company shall provide Hobbs with a suitable automobile in
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     Switzerland, with the Company bearing all related costs (insurance,
     registration, leasing, fuel, maintenance, etc.).

6.   Accommodations and Related Expenses. The Company shall pay for a suitable
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     rental unit for Hobbs in or near Geneva, Switzerland, including all
     utilities, parking and related costs. The Company shall also pay for a one-
     time relocation allowance of one-month's salary in lieu of expenses for
     setting up Hobbs' new household, and a similar allowance upon Hobbs' return
     to the U.S. If Hobbs should need to engage the services of a destination
     services company or real estate agent for the purpose of finding suitable
     housing in Switzerland, the Company shall pay for the charges and fees
     related to such company or agent.

     In Switzerland, the Company shall provide Hobbs with home telephone lines
     to support his business requirements, as well as mobile telephone service.
     In addition, the Company shall 
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     reimburse Hobbs for grounds maintenance and utilities costs incurred by
     Hobbs with respect to his permanent residence in the United States.

7.   Freight. The Company shall pay for the shipment of necessary household
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     goods to Switzerland (and back) for Hobbs, as well as for associated
     packing and in-transit insurance in an amount not to exceed $100,000. The
     Company shall also provide, if necessary, the services of a professional
     organizer to facilitate Hobbs' move to and from Switzerland.

8.   Work Permit. The Company shall secure a work permit for Hobbs (as well as a
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     permit for Hobbs' wife, if she does not have the services of her employer
     for such purpose).

9.   COLA. The Company shall pay to Hobbs, if indicated by a Runzheimer or
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     similar analysis of the differential cost of living between Metropolitan
     Washington, D.C. and Geneva, Switzerland, a Cost of Living Adjustment (in
     the form of monthly additions to his base salary), not to exceed 15% of
     such salary.


AGREED as of this 1/st/ day of October, 1998.



    /s/ Harold S. Wills
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       For PSINet Inc.


    /s/ Harry Hobbs
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       Harry Hobbs