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                                                                   EXHIBIT 10.10

November 12, 1998

Mr. Lawrence Winkler
1230 Eton Court
Washington, DC  20007

Dear Larry:

This letter confirms our offer to you of further employment by PSINet Inc. (the
"Company"), and sets forth the terms and conditions which shall govern such
employment as outlined below.  This offer is subject to ratification by the
Company's Board of Directors.

1.   EMPLOYMENT:

a)   The Company employed you as Director, Treasury, Capital Markets and
Investor Relations since December 1, 1997, and hereby promotes you to Vice
President and Treasurer reporting to Senior Vice President Chief Financial
Officer. This is a corporate officer position and as an officer of the Company
you must stand for election by the Board of Directors each year. You accept the
employment and agree to remain in the employ of the Company, and, except during
vacation periods and sickness, to provide during standard business hours a
minimum of forty (40) hours per week of management services to the Company, as
determined by and under the direction of the Senior Vice President and Chief
Financial Officer.

b)   During your employment you will, except during vacations, periods of
illness, and other absences beyond your reasonable control, devote your best
efforts, skill and attention to the performance of your duties on behalf of the
Company.


1.   COMPENSATION:

a)   BASE SALARY.  The Company shall pay you a base salary at the rate of
$175,000 per annum. Your base salary shall be subject to additional increases at
the discretion of the Company's Board of Directors. Your base salary shall be
payable in such installments as the Company regularly pays its other salaried
employees, subject to such deductions and withholdings as may be required by law
or by further agreement with you.

b)   BONUS COMPENSATION.  The Company will pay you a bonus upon the successful
completion of the objectives established for your performance, which will be
measured on or about December 31, 1998. The performance criteria will be issued
separately by the Senior Vice President an Chief Financial Officer, and may be
changed with mutual fairness, from time to time as situations develop. Your 1998
bonus for the period ending December 31, 1998 will be total of up to $50,000.
Separate criteria will be established for your bonus for the year starting
January 1, 1999. Additional compensation may be paid based upon achievement of
company financing plans..

c)   INCENTIVE STOCK OPTIONS.  PSINet Inc. has granted you an additional 50,000
options, subject to Board Approval, to purchase shares of PSINet Inc.'s common
stock (the "Options") pursuant to its Executive Stock Incentive Plan (the
"Plan"). Such Options shall be evidenced by an option agreement in such form as
required by the Plan. Among other terms and provisions prescribed by the Plan,
the option agreement shall provide that (a) the exercise price of the Options
shall be the price per share of the Company's common stock as reported by the
NASDAQ Stock Market at the close of business on your start date, (b) the Options
shall not be exercisable after the expiration of ten (10) years from the date
such Options are granted, and (c) the stock shall vest ratably, monthly, over
forty-eight (48) months, provided that for each month's vesting purposes you
continue to be employed full time by the Company or one of its subsidiaries
during such month, and provided that the Company's Board of Directors ratifies,
no less often
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than annually, that you have met the performance standards and criteria set for
you for the preceding period.


3.   EMPLOYEE BENEFITS.  You shall be provided employee benefits, including
(without limitation) 401(k), four weeks' paid vacation, and life, health,
accident and disability insurance under the Company's plans, policies and
programs available to employees in accordance with the provisions of such plans,
policies and programs.


4.   TERMINATION:

a)   The Company may terminate your employment at any time for "Cause" as
defined in section 4(c) hereof. Upon such termination, the Company will provide
written notice whether it has elected to use the non-competition restrictions
set forth in section 5(a) hereof. Your employment may also be terminated by the
Company at any time without Cause provided the Company shall have given you
thirty (30) days' prior written notice of such termination. That written notice
must state whether the Company has elected to use the non-Competition
restriction (which decision may not be rescinded). If you are terminated by the
Company without Cause within the initial one-year term of your employment, you
will be paid ninety (90) days' severance pay. If you are terminated by the
Company without cause thereafter, you will be paid one hundred eighty day
severance pay. In addition, your employment may be terminated by you at any time
for any reason, provided you shall have given the Company at least thirty (30)
days' prior written notice of such termination. By the thirtieth day the Company
must notify you in writing whether it has elected to use the non-Competition
restriction not being in place.

b)   Subject to your compliance with your obligations under Section 5 hereof, in
the event that your employment terminates or is terminated by you or the Company
for any reason other than for Cause, and the Company has elected to use the non-
Competition restriction, you shall be entitled, for a period of twelve (12)
months after termination of employment, to the following (collectively, the
"Termination Payments"):  (I) your then current rate of base salary as provided
in Section 2;  (ii) all life insurance and health benefits, disability insurance
and benefits and reimbursement theretofore being provided to you;  and (iii)
Company contributions, to the extent permitted by applicable law, to a SEP-IRA,
Keogh or other retirement mechanism selected by you sufficient to provide the
same level of retirement benefits you would have received if you had remained
employed by the Company during such 12-month period.  The Company shall make up
the difference in cash payments directly to you to the extent that applicable
law would not permit it to make such contributions.

c)   The Company shall have "Cause" for termination of your employment by reason
of any breach of your agreement not to compete pursuant to Section 5 hereof,
your committing an act materially adversely affecting the Company which
constitutes wanton or willful misconduct, your conviction of a felony, or any
material breach by you of this Agreement.


5.   AGREEMENT NOT TO COMPETE.

a)   In consideration of your employment pursuant to this Agreement and for
other good and valuable consideration, the receipt and adequacy of which is
hereby acknowledged, you covenant to and agree with the Company that, so long as
you are 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), you shall not, without the
prior written consent of the Company, either for yourself or for any other
person, firm or corporation, manage, operate, control, participate in the
management, operation or control of or be employed by any other person or entity
which is engaged in providing Internet-related network or communications
services competitive with the Internet-related network or communications
services offered to customers by the Company as of the date of termination or
within six (6) months thereafter. The foregoing shall in no event restrict you
from: (I) writing or teaching, whether on behalf of for-profit, or not for
profit institution(s); (ii) investing (without participating in management
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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 network or communication services that are competitive with the
Internet-related network or communications services offered by the Company as of
the date of termination of employment or within six (6) months thereafter.

b)   You may request permission from the Company's Board of Directors to engage
in activities, which would otherwise be prohibited by Section 5(a). The Company
shall respond to such request within thirty (30) days after receipt. The Company
shall notify you in writing if it becomes aware of any breach or threatened
breach of any of the provisions in Section 5(a), and you shall have thirty (30)
days after receipt of such notice in which to cure or prevent the breach, to the
extent that you are able to do so. You and the Company acknowledge that any
breach or threatened breach by you of any of the provisions in Section 5(a)
above cannot by 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 you
breached any of such provisions, you shall not be entitled to any Termination
Payments from and after date of the breach. In such event, you 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 you did not breach such provision or determines such provision
to be unenforceable as applied to your conduct, you 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.


6.   INTELLECTUAL PROPERTY.  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 you 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. You
automatically assign, and shall assign at the time of creation of the Work
Product, without any requirement of further consideration, any right, title, or
interest you may have in such Work Product, including any copyrights or other
intellectual property rights pertaining thereto. Upon request of the Company,
you 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.


7.   TRANSFERABILITY.

a)   As used in this Agreement, the term "Company" shall include any successor
to all or part of the business or assets of the Company, who shall assume and
agree to perform this Agreement.

This Agreement shall inure to the benefit of and be enforceable by you and your
personal and legal representatives, executors, administrators, heirs,
distributees, devisees and legatees.

b)   Except as provided under paragraph (a) of this Section 8, neither this
Agreement nor any of the rights or obligations hereunder shall be assigned or
delegated by any party hereto without the prior written consent of the other
party.


8.   SEVERABILITY.  The invalidity or unenforceability of any particular
provision of this Agreement shall not affect the other provisions hereof, and
this Agreement shall be construed in all respects as if such invalid or
unenforceable provision were omitted. If a court of competent jurisdiction
determines that any particular provision of this Agreement is invalid or
unenforceable, the court shall restrict the
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provision so as to be enforceable. However, if the provisions of Section 5 shall
be restricted, a proportional reduction shall be made in the payments under
Section 4.

10.  ENTIRE AGREEMENT; WAIVERS.  This letter Agreement contains the entire
agreement of the parties concerning the subject matter hereof and supercedes and
cancels all prior agreements, negotiations, correspondence, undertakings and
communications of the parties, oral or written. No waiver or modification of any
provision of this Agreement shall be effective unless in writing and signed by
both parties.

11.  NOTICES.  Any notices, requests, instruction or other document to be given
hereunder shall be in writing and shall be sent certified mail, return receipt
requested, addressed to the party intended to be notified at the address of such
party as set forth at the head of this agreement or such other address as such
party may designate in writing to the other.

12.  GOVERNING LAW.  THIS LETTER AGREEMENT SHALL BE SUBJECT TO, GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO
CONTRACTS TO BE PERFORMED WHOLLY WITHIN THAT STATE.

13.  COUNTERPARTS.  This letter 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.

Please confirm your agreement with the foregoing by signing and returning one
copy of this letter Agreement to the undersigned, whereupon this letter
agreement shall become a binding agreement between you and the Company.

Sincerely,

PSINet Inc.


By: /s/Edward D. Postal
   --------------------
   Edward D. Postal
   Senior Vice President and Chief Financial Officer


Accepted and Agreed to as of November 13, 1998:


By: /s/Lawrence Winkler
   --------------------
   Lawrence Winkler