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                                                                    EXHIBIT 10.4

October 13, 1998


Mr. E. A "Ted" Davis
21 Pheasant Run Drive
Basking Ridge, NJ  07920

Dear Mr. Davis:

This letter confirms our offer to you of 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 satisfactory completion
of reference checks and ratification by the Company's Board of Directors, but
otherwise shall remain open until noon on Wednesday, October 14, 1998.

1.  EMPLOYMENT.

A)  The Company agrees to employ you as President - PSINetworking, reporting to
the Chief Operating Officer (COO) of the Company or his designee.  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 begin work on or before Wednesday, October 14, 1998, and 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 COO.

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.

2.  COMPENSATION.

A)  BASE SALARY.  The Company shall pay you a base salary at the rate of
$225,000 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 January 15, 1999.  The performance criteria will be issued
separately by the COO, and may be changed, with mutual fairness, from time to
time as situations develop.  The target bonus for the period ending December 31,
1998 will be the pro-rated sum proportional to the fraction of the calendar year
you worked from your 
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start date through December 31, 1998 (on the basis of an annualized bonus of up
to $125,000). Separate criteria will be established for your entitlement for the
year starting January 1, 1999.

C)  INCENTIVE STOCK OPTIONS.  Effective upon your start date,  the Company shall
grant you options, subject to Board approval, to purchase 96,000 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 than annually, that you
have met the performance standards and criteria set for you for the preceding
period.

D)  CAR ALLOWANCE OR CAR POLICY.  The Company plans to implement a Company car
policy for which you would be eligible.  Until such a policy is implemented, the
Company will cover the rental or short term leasing cost (through normal expense
reimbursement) of a suitable executive vehicle up to the value of $600.00 per
month.

E)  RELOCATION ALLOWANCE.  The Company will provide you with a relocation
allowance of up to $70,000 to assist you in relocating your residence from
Basking Ridge, NJ to a comparable home in Northern Virginia.  The relocation
allowance will include reasonable expenses of sale, moving, interim living and
resettlement in the new home.  Income taxes will be withheld from this sum.  You
may be eligible for a refund of some portion of the taxes withheld upon filing
your current year's US tax return.  Should you voluntarily terminate your
employment with the Company within one (1) year from the date you commence
employment at our Virginia offices, you agree to reimburse the Company for the
entire sum of this allowance within ninety (90) days of your date of
termination.

3.  EMPLOYEE BENEFITS.  You shall be provided employee benefits, including
(without limitation) 401(k), four (4) 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)  Your employment with the Company may be terminated by the Company 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

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(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 (1) year term of your employment,
you will be paid one hundred eighty (180) days' 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. Such decision may
not be rescinded. Failure of the Company to so notify you shall result in 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 twelve (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 your 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 communication 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 or
operation) in the securities of any private or publicly traded corporation or
entity; or (iii) after termination 

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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 Director's 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 will 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 6(a) 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 thirty (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 twelve percent (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 twelve percent (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.  NONDISCLOSURE AGREEMENT.  You agree to sign the Company's Nondisclosure
Agreement before commencing employment with PSINet Inc.

8.  TRANSFERABILITY.

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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 or 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.

9.  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 provision so as to be enforceable.
However, if the provisions of Section 6 shall be restricted, a proportional
reduction shall be made in the payments under Section 5.

10. ENTIRE AGREEMENT; WAIVERS.  This letter Agreement contains the entire
agreement of the parties concerning the subject matter hereof and supersedes 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 for 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,

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PSINet Inc.


By:  /s/ Harold S. Wills
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     Harold S. Wills
     President and Chief Operating Officer


Accepted and Agreed to as of October 14, 1998:


By:  /s/ Edward A. Davis
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     E.A. "Ted" Davis

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