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                                                                 EXHIBIT 10.21

                        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 Joseph
Rymsza ("RYMSZA"), whose address is 11211 Elmview Place, Great Falls, VA 22066.

       WHEREAS, Rymsza has been employed by Cysive; and

       WHEREAS, Rymsza's employment with Cysive terminated, effective January
15, 2001; and

       WHEREAS, Rymsza 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. Rymsza'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 Rymsza
his final paycheck for services rendered up and through January 19, 2001.

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

              c.     Rymsza agrees to provide written instructions to Merrill
Lynch on the disposition of Rymsza'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 Rymsza's termination, such coverage
to end on December 31, 2001.

              e.     Following December 31, 2001, Rymsza 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. Rymsza agrees to return any and all Cysive computer
related equipment assigned to Rymsza, 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 order




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on or before January 31, 2001. Rymsza further agrees to return to Cysive on or
before January 19, 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 Rymsza 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 Rymsza 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 Rymsza's employment agreement dated as of
January 1, 2000 (the "EMPLOYMENT AGREEMENT"), Cysive agrees to distribute to
Rymsza 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 Rymsza $18,839.80 which amount
represents the estimated income taxes payable with respect to the Split Dollar
Premium (the "INCOME TAX ADJUSTMENT"). Rymsza acknowledges that he is not
entitled to the Payment, the Split Dollar Policy 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, Rymsza 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) Rymsza 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 Rymsza 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
Rymsza has a non-forfeitable right under any ERISA pension 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



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law, and any amendments to any of the foregoing. Such release includes, but is
not limited to, any claim Rymsza or his counsel may have, or had, for payment of
attorney's fees or reimbursement of expenses. Furthermore, except as provided
herein, Rymsza 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 Rymsza pursue such a Claim.
However, this does not preclude Rymsza from exercising his right to apply for
unemployment benefits.

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

       6.     ARBITRATION. Except in the case where equitable relief is
permitted, all disputes between Rymsza 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 Rymsza 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. Both parties 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 their respective accountants, attorneys,
income tax preparers or similar professionals, each of whom shall be bound by
this confidentiality requirement. Both parties will not make any statement or
comment to any third party, including Cysive employees, that would disparage or
derogate each other and/or any of Cysive's employees. The provisions of this
paragraph are material terms of this Agreement.

       8.     MISCELLANEOUS. (a) Rymsza 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, Rymsza'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, Rymsza 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/ JOSEPH RYMSZA
                                    ----------------------------------------
                                    JOSEPH RYMSZA
                                    DATE:   1/10/2001
                                         -----------------------------------


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