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                                                                  EXHIBIT 10.20


                        SEPARATION AGREEMENT AND RELEASE

       This Separation Agreement and Release ("AGREEMENT") is entered into as of
the 10th day of January, 2001 by and between Cysive, Inc. ("CYSIVE"), and Robert
Rubinstein ("RUBINSTEIN"), whose address is 1913 Upper Lake Drive, Reston, VA
20191.

       WHEREAS, Rubinstein has been employed by Cysive; and

       WHEREAS, Rubinstein's employment with Cysive terminated, effective
January 19, 2001; and

       WHEREAS, Rubinstein and Cysive wish to resolve amicably all outstanding
issues between them.

       NOW THEREFORE, in consideration of the mutual promises and releases
contained herein and for other good and valuable consideration, the sufficiency
of which is hereby acknowledged, the parties agree as follows:

       1.     TERMINATION. Rubinstein's employment with Cysive terminated,
effective January 19, 2001.

       2.     SALARY AND BENEFITS. Upon execution of this Agreement, the parties
agree as follows:


              a.     On or after February 2, 2001, Cysive will provide
Rubinstein his final paycheck for services rendered up and through January 19,
2001.

              b.     So long as Rubinstein has submitted complete and accurate
time records up through January 19, 2001, Cysive will provide Rubinstein on or
before February 2, 2001 with payment for accrued and unused vacation.

              c.     Rubinstein agrees to provide written instructions to
Merrill Lynch on the disposition of Rubinstein's funds, if any, held in a 401(k)
account.

              d.     Cysive shall continue to provide medical and dental health
coverage of the type in existence prior to Rubinstein's termination, such
coverage to end on December 31, 2001.

              e.     Following December 31, 2001, Rubinstein shall be entitled
to elect to continue, at his cost, coverage under the Cysive health plan, in
accordance with the health care continuation coverage provisions of the
Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA").

       3.     EQUIPMENT. Rubinstein agrees to return any and all Cysive computer
related equipment assigned to Rubinstein, including without limitation, all
laptops, servers, computers, docking stations, monitors, accessories and
printers (the "COMPUTER EQUIPMENT") to Elaine Schincariol at 10780 Parkridge
Blvd., Suite 400, Reston, Virginia 20191 in good working



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order on or before February 28, 2001. Rubinstein further agrees to return to
Cysive on or before February 28, 2001, all other Cysive personal property,
including without limitation, all pagers, cell phones, palm pilots (or the
like), calling cards and corporate credit cards (e.g., Diners Club).

       4.     SEVERANCE. (a) Subject to the terms and conditions contained
herein, Cysive shall provide Rubinstein a severance payment equal to
$137,388.45, less usual taxes and withholdings (the "PAYMENT"), which payment
shall be made at a bi-weekly rate of $5,607.70, less usual taxes and
withholdings, and shall be made with Cysive's regular payroll beginning with
Cysive's February 2, 2001 salary disbursement and ending on Cysive's December
21, 2001 salary distribution, provided, however, that in the event Rubinstein
fails to return the Computer Equipment pursuant to SECTION 3, the Payment shall
be reduced by $2,000.00 (the "COMPUTER DEPOSIT"). Cysive will pay the Computer
Deposit promptly upon receipt of the Computer Equipment, in good working order,
but in no event later than March 31, 2001

              (b)    Notwithstanding the forfeiture requirements contained in
the sixth sentence of SECTION 1(c) of Rubinstein's employment agreement dated as
of January 1, 2000 (the "EMPLOYMENT AGREEMENT"), Cysive agrees to distribute to
Rubinstein on or before February 2, 2001 the split dollar life insurance policy
(the "SPLIT DOLLAR POLICY") and to release any and all security interests in the
Split Dollar Policy created under that certain split dollar collateral
assignment (the "SPLIT DOLLAR COLLATERAL ASSIGNMENT"). Additionally, on or
before February 2, 2001, Cysive agrees to pay to Rubinstein $19,833.65 which
amount represents the estimated income taxes payable with respect to the Split
Dollar Premium (the "INCOME TAX ADJUSTMENT"). Rubinstein acknowledges that he is
not entitled to the Payment, the Split Dollar Policy, the release of the
security interest or the Income Tax Adjustment but for his execution of this
Agreement and the release provision of SECTION 5 in particular. Except as set
forth herein, Rubinstein acknowledges that, after January 19, 2001, he is not
entitled to any further compensation from Cysive pursuant to this Agreement, his
employment or any other source.

       5.     RELEASE. (a) Rubinstein hereby releases, remises and discharges
Cysive and each and every one of its former or current directors, officers,
employees, members, agents, successors, predecessors, subsidiaries, assigns and
attorneys of and from all actions, causes of action, claims or complaints
(collectively, "CLAIMS"), known or unknown, in law or equity which Rubinstein or
his heirs, executors, administrators, assigns, agents, representatives or
attorneys ever had or now has by reason of any matter, cause or thing whatsoever
at any time up to and including the date of execution of this Agreement,
including but not limited to any Claim for any alleged violation of any federal,
state or local statutes, regulations or ordinances, including but not limited to
the AGE DISCRIMINATION IN EMPLOYMENT ACT (29 U.S.C. SECTIONS 621 ET SEQ.), Title
VII of the Civil Rights Acts of 1964, as amended (42 U.S.C. Sections 2000e et
seq.), Sections 1981 through 1988 of Title 42 of the United States Code (42
U.S.C. Sections 1981-88), the Americans With Disabilities Act (42 U.S.C.
Sections 12101 et seq.), the Fair Labor Standards Act (29 U.S.C. Sections 201 et
seq.), the Family and Medical Leave Act (29 U.S.C. Sections 2601 et seq.), the
Employee Retirement Income Security Act (other than any accrued benefit(s) to
which Rubinstein has a non-forfeitable right under any ERISA pension


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benefit plan), the California Fair Employment and Housing Act, the California
Family Rights Act, the Virginia Human Rights Act, the Illinois Human Rights Act,
any other applicable state law, and any amendments to any of the foregoing. Such
release includes, but is not limited to, any claim Rubinstein or his counsel may
have, or had, for payment of attorney's fees or reimbursement of expenses.
Furthermore, except as provided herein, Rubinstein shall not pursue any such
Claim in any court, agency, board, committee or forum whatsoever, and shall
reimburse Cysive for all fees and expenses associated with Cysive's defense
should Rubinstein pursue such a Claim. However, this does not preclude
Rubinstein from exercising his right to apply for unemployment benefits.

              (b)    Cysive hereby advises Rubinstein to consult with an
attorney prior to executing this Agreement.

       6.     ARBITRATION. Except in the case where equitable relief is
permitted, all disputes between Rubinstein and Cysive or any of its current,
former or future parents, subsidiaries or affiliates shall be submitted to final
and binding arbitration. This arbitration shall take place in Fairfax County,
Virginia, under the Employment Dispute Resolution Rules of the American
Arbitration Association before an experienced employment arbitrator licensed to
practice law in Virginia selected in accordance with those rules. The arbitrator
may not modify or change this Agreement in any way. Each party shall pay for its
own costs and expenses, including without limitation, attorneys' fees and costs.
If any party prevails on a statutory claim which affords attorneys' fees and
costs, the arbitrator may award reasonable attorneys fees and/or costs to the
prevailing party. At the conclusion of the Arbitration the arbitrator shall
issue a written award. Arbitration in this manner shall be the exclusive remedy
for any dispute. Should Rubinstein or Cysive attempt to resolve an dispute by
any method other than arbitration pursuant to this Section, the responding party
will be entitled to recover from the initiating party all damages, expenses, and
attorneys' fees incurred as a result of the breach.

       7.     CONFIDENTIALITY. Rubinstein shall keep confidential the terms and
content of this Agreement, the fact of the execution of this Agreement and the
circumstances leading to the execution of this Agreement, and shall not disclose
them except as necessary to his accountants, attorneys, income tax preparers or
similar professionals, each of whom shall be bound by this confidentiality
requirement. Rubinstein will not make any statement or comment to any third
party, including Cysive employees, that would disparage or derogate Cysive
and/or any of its employees. The provisions of this paragraph are material terms
of this Agreement.

       8.     MISCELLANEOUS. (a) Rubinstein acknowledges that he has read
carefully this entire Agreement, including but not limited to the release
provision of Section 5 and affirms that he is executing this Agreement
voluntarily and of his own free act and deed.

              (b)    If any portion of this Agreement is void or deemed
unenforceable for any reason, the unenforceable portion shall be deemed severed
from the remaining portions of this Agreement which shall otherwise remain in
full force and effect.



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              (c)    This Agreement is governed by the law of the Commonwealth
of Virginia, without regards to its conflict of laws provisions.

              (d)    This Agreement constitutes the entire agreement between the
parties and supersedes any and all prior agreements or understandings.
Notwithstanding the prior sentence, Rubinstein's obligations of non-competition,
non-disclosure and all other obligations as contained in his employment
agreement remain in full force and effect and are incorporated by reference
herein. This Agreement may be modified only in writing signed by both parties.

              (e)    This Agreement does not, and shall not in any way be
construed to, constitute an admission of wrongdoing or liability by either
party.




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       By signing this document, Rubinstein agrees and understands that he is
releasing unknown as well as known claims in exchange for the compensation set
forth above.


                                    CYSIVE, INC.


                                    By: /s/ NELSON A. CARBONELL, JR.
                                       ----------------------------------
                                             Nelson A. Carbonell, Jr.
                                             Chairman, President and
                                             Chief Executive Officer




                                    EMPLOYEE:

                                     /s/ ROBERT RUBINSTEIN
                                    -------------------------------------
                                    ROBERT RUBINSTEIN
                                    DATE:  1/10/2001
                                        ---------------------------------


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