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                                  EXHIBIT 10.20

                           OFFER LETTER OF TERRI ALLEN

                                     Revised
                                  28 June 2001

Ms. Terri Allen
9932 Koupela Drive
Raleigh, N.C.   27614



Dear Terri:

GTSI Corp. ("GTSI") is pleased to offer you the position of Senior Vice
President, Sales. In this position, you will report to John Spotila, Chief
Operating Officer and General Counsel. We would like your employment to commence
as soon as possible, preferably by the Projected Start Date referred to below.

Your total annual target compensation will be $315,000. This will consist of a
base salary of $215,000 ($8,958.33 semi-monthly) plus participation in the Sales
Incentive Compensation Plan. At 100% goal attainment, your annual target bonus
under this plan will be $100,000. GTSI will guarantee 100% of your pro-rated
target bonus for the first three months of employment (i.e.: 3 equal
installments of 8,333.33 per month). GTSI will discuss your incentive plan with
you in more detail, during your first three months of active employment.

As a further incentive for you, GTSI will pay for the moving expenses you incur
during your relocation process from North Carolina to Virginia in an amount not
to exceed $65,000. These expenses include household goods moving costs,
temporary housing, as well as Realtor fees associated with the sale of your
current residence for up to 12 months from your first day of employment. Please
reference the attached policy for additional details. To qualify, expense
amounts must be approved by GTSI prior to your obtaining services. Please
understand that you will be required to repay all such expenses paid on your
behalf should your employment with GTSI end voluntarily or for cause before the
end of one year of employment.

You will be eligible, on the first of the month following your hire date, to
join the GTSI benefits plan which would include life insurance, comprehensive
medical, dental and vision insurance for yourself and dependents on a
contributory basis if you so elect. We will provide you with detailed
information concerning your complete benefits package upon employment. You will
be eligible for three weeks of vacation for the year 2001 and for each calendar
year thereafter. As with all GTSI employees, you will be subject to all Company
policies and procedures.

If your employment ceases for any reason other than for "cause" (1) you will
receive a severance equal to 6 months' base salary paid out over the following
six months. The option exercise period would be


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1 Cause - Termination by GTSI of an officer's employment for "Cause" means
termination as a result of (i) acts or omissions involving unacceptable
performance or conduct (examples of which include, but are not limited to:
failure or refusal to perform assigned duties or to follow Company policies, as
determined in the sole discretion of the Company; commission of sexual
harassment; excessive absenteeism; unlawful use or possession of drugs or misuse
of legal drugs or alcohol; misappropriation of a Company asset or opportunity;
the offer, payment, solicitation or acceptance of any bribe or kickback with
respect to the Company's business; the assertion, representation or
certification of any false claim or statement to a Company customer; or
indictment or conviction for any felony whatsoever or for any misdemeanor
involving moral turpitude); (ii)

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extended for five months to be coterminous with the salary. This severance plan
expires 12 months from your date of hire.

In the case of a "change in control," (2) you will receive immediate vesting of
all outstanding stock options.

As part of your compensation package, we will recommend to the Compensation
Committee of the Company's Board of Directors that the Committee grant to you a
nonstatutory stock option ("Option"), effective as of the date of grant (the
"Grant Date"), to purchase 30,000 shares of the Company's Common Stock. The
exercise price will be equal to the closing price of the Company's Common Stock
on the Grant Date or, if there has been no trading in the Company's Common Stock
on the Grant Date, then the immediately preceding date upon which the Company's
Common Stock is so traded (as reported the following business day in THE WALL
STREET JOURNAL). Your options will vest and be exercisable, cumulatively, in
four equal annual installments with the first installment vesting on the first
anniversary of the Grant Date, and will be subject to the terms and provisions
of the stock option agreement evidencing the grant of the Option. Your Option
shall expire, to the extent not previously exercised, upon the earlier of seven
years from the date of initial vesting or three months after you cease to be a
GTSI employee. Since this stock option offer is by law subject to approval by
GTSI's Board of Directors or a Committee thereof, no one at GTSI can promise or
ensure such approval. Nonetheless, we envisage Committee approval without
problem.

To comply with the Immigration Reform and Control Act, you will be required to
verify citizenship by completing the enclosed form and presenting the requested
documents on the first day of employment. Employment is contingent upon
satisfactory references, successful completion of pre-employment drug screening,
and the completion of a GTSI Corp. non-disclosure form.

Your employment at GTSI will be an "at will" relationship; that is, either party
may end it at any time. Neither this offer of employment, nor your acceptance,
nor our maintenance of personnel policies, procedures, and benefits creates a
minimum term of employment. Please also be advised that it is GTSI's policy that
employees should discuss salary issues only with their manager. For the first
120 days of employment, you will serve an initial introductory period.

GTSI regards Customer Relationship Management (CRM) as a fundamental part of its
strategy. CRM, as implemented through our contact database, is a unifying factor
that manages all forms of communication with our customers, increasing the value
of GTSI to our customers and the value of our customers to GTSI. To make this
effective, we need the support and commitment of every GTSI employee. We will
need your full cooperation in this regard.

By executing this letter, you represent and warrant to GTSI that you are not
currently subject to any express or implied contractual obligations to any of
your former employers under any secrecy, non-competition or other agreements or
understandings, except for any of which you have furnished copies or written
summaries to me, prior to your execution of this letter.


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inability for any reason to perform the essential functions of the position; or
(iii) other conduct deemed by the Company to be inappropriate for an officer or
harmful to the Company's interests or reputation.
2 Change of control is defined as (i) control of 50% or more of outstanding
shares of GTSI; (ii) a change in a majority of the Company Board of Directors if
the change occurred during any 12 consecutive months, and the new directors were
not elected by the Company's shareholders or by a majority of the directors who
were in office at the beginning of the 12 months; or (iii) the stockholders of
the Company approve a merger or consolidation of the Company with any other
corporation, other than a merger or consolidation which would result in the
voting securities of the Company outstanding immediately prior thereto
continuing to represent more than 50% of the combined voting power of the voting
securities of the Company or such surviving entity outstanding immediately after
such merger or consolidation.

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This letter contains our entire understanding with respect to your employment at
GTSI. It supersedes all prior or contemporaneous representations, promises or
agreements concerning this subject, whether in written or oral form, and whether
made to or with you by any employee or other person affiliated with GTSI or any
actual or perceived agent.

Terri, we believe you will provide GTSI with the creativity and experience to
contribute to continued GTSI growth. We also believe that GTSI can provide you
with opportunities for professional growth and financial return. We look forward
to the commencement of your employment with GTSI and expect a mutually
fulfilling and rewarding relationship.

Please acknowledge your acceptance of this offer by signing the enclosed copy of
this letter, and returning it to me as soon as possible along with your
completed application of employment.


Sincerely,                            Acknowledged/Accepted

/s/ Bridget Atkinson
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Bridget Atkinson                      /s/ Terri Allen        Date  July 29, 2001
Vice President                        ---------------------
Human Resources                       Terri Allen



                                      Projected Start Date:   11 July 2001





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