<PAGE>



                                                                   EXHIBIT 10.20

                     COLLATERAL ASSIGNMENT, PATENT MORTGAGE
                             AND SECURITY AGREEMENT

         This Collateral Assignment, Patent Mortgage and Security Agreement (the
"Assignment") dated as of the 18 day of April, 2002, and to become effective in
 ----------
accordance with the provisions set forth below, from THE MARASCO NEWTON GROUP
LTD., a Virginia corporation (the "New Subsidiary"), in favor of SUNTRUST BANK,
                                   --------------
a Georgia banking corporation ("Assignee").
                                --------

                                    RECITALS
                                    --------

         Assignee has entered into a Loan Agreement dated as of August 15, 2001
(as amended, modified or supplemented from time to time, the "Loan Agreement,"
                                                              --------------
the terms defined therein and not otherwise defined herein being used herein as
therein defined) with SRA International, Inc., a Delaware corporation (the
"Company"), Systems Research and Applications Corporation, a Virginia
---------
corporation ("SRA"), SRA Technical Services Center, Inc., a Delaware corporation
              ---
("STSC"), and each other Subsidiary that becomes a party to the Loan Agreement
  ----
in accordance with the provisions set forth therein (together with the Company,
SRA, and STSC, collectively, "Assignors," and individually, "Assignor").
                              ---------                      --------
Simultaneously herewith, the New Subsidiary shall enter into the Assumption
Agreement, dated as of 18 April 2002, with the Lender (as amended, modified or
supplemented from time to time, the "Assumption Agreement"), thereby becoming a
                                     --------------------
Borrower under the Loan Agreement in accordance with the terms and conditions
thereof, and, by its execution and delivery hereof, the New Subsidiary shall
become an Assignor. It is a condition precedent to the making of the Loans and
the issuance of Letters of Credit by Assignee under the Loan Agreement that each
Assignor shall have assigned certain property to Assignee in accordance with
this Assignment.

         NOW, THEREFORE, FOR VALUABLE CONSIDERATION, THE RECEIPT AND SUFFICIENCY
OF WHICH ARE ACKNOWLEDGED, THE PARTIES HERETO AGREE AS FOLLOWS:

         1. Assignment, Patent Mortgage and Grant of Security Interest. As
            ----------------------------------------------------------
collateral security for the prompt and complete payment and performance of the
Obligations (as defined below), the New Subsidiary hereby assigns, transfers,
conveys and grants a security interest and mortgage to Assignee, as security,
but not as an ownership interest, in and to its entire right, title and interest
in, to and under the following (all of which shall collectively be called the
"Collateral"), provided that the foregoing assignment, transfer, conveyance,
 ----------
grant and mortgage shall not become effective unless and until a Security Event
shall occur under the Loan Agreement:

                  (a) All present and future United States registered copyrights
and copyright registrations, including, without limitation, the registered
copyrights listed in Exhibit A-1 to this Assignment (and including all of the
                     -----------
exclusive rights afforded a copyright registrant in the United States under 17
U.S.C. ss.106 and any exclusive rights which may in the future arise by act of
Congress or otherwise) and all present and future applications for copyright
registrations (including applications for copyright registrations of derivative
works and compilations) (collectively, the "Registered Copyrights"), and any and
                                            ---------------------
all royalties, payments, and other



<PAGE>

amounts payable to the New Subsidiary in connection with the Registered
Copyrights, together with all renewals and extensions of the Registered
Copyrights, the right to recover for all past, present, and future infringements
of the Registered Copyrights, and all computer programs, computer databases,
computer program flow diagrams, source codes, object codes and all tangible
property embodying or incorporating the Registered Copyrights, and all other
rights of every kind whatsoever accruing thereunder or pertaining thereto;

                  (b) All present and future copyrights, or contract or license
rights arising from agreements by which the New Subsidiary is a licensee, which
are not registered in the United States Copyright Office (the "Unregistered
                                                               ------------
Rights"), whether now owned or hereafter acquired, including without limitation
------
the Unregistered Rights listed in Exhibit A-2 to this Assignment, and any and
                                  -----------
all royalties, payments, and other amounts payable to the New Subsidiary in
connection with the Unregistered Rights, together with all renewals and
extensions of the Unregistered Rights, the right to recover for all past,
present, and future infringements of the Unregistered Rights, and all computer
programs, computer databases, computer program flow diagrams, source codes,
object codes and all tangible property embodying or incorporating the
Unregistered Rights, and all other rights of every kind whatsoever accruing
thereunder or pertaining thereto. The Registered Copyrights and the Unregistered
Rights collectively are referred to herein as the "Copyrights";
                                                   ----------

                  (c) All right, title and interest in and to any and all
present and future license agreements with respect to the Copyrights, including
without limitation the license agreements listed in Exhibit A-3 to this
                                                    -----------
Assignment (the "Licenses");
                 --------

                  (d) All present and future accounts, accounts receivable and
other rights to payment arising from, in connection with or relating to the
Copyrights;

                  (e) Any and all trade secrets, and any and all intellectual
property rights in computer software and computer software products now or
hereafter existing, owned by the New Subsidiary;

                  (f) Any and all design rights which may be owned by the New
Subsidiary, now or hereafter existing, created, acquired or held;

                  (g) All patents, patent applications and like protections
including, without limitation, improvements, divisions, continuations, renewals,
reissues, extensions and continuations-in-part of the same, including without
limitation the patents and patent applications set forth on Exhibit B attached
                                                            ---------
hereto (collectively, the "Patents"), and any and all royalties, payments, and
                           -------
other amounts payable to the New Subsidiary in connection with the Patents,
together with all renewals and extensions of the Patents, the right to recover
for all past, present, and future infringements of the Patents, and all computer
programs, computer databases, computer program flow diagrams, source codes,
object codes and all tangible property embodying or incorporating the Patents,
and all other rights of every kind whatsoever accruing thereunder or pertaining
thereto;

                  (h) Any trademark and servicemark rights, whether registered
or not, applications to register, and the entire goodwill of the business of the
New Subsidiary connected with and symbolized by such trademarks, including
without limitation those set forth on Exhibit C attached hereto (collectively,
                                      ---------
the "Trademarks"), and any and all royalties, payments, and
     ----------

                                       2


<PAGE>


other amounts payable to the New Subsidiary in connection with the Trademarks,
together with all renewals and extensions of the Trademarks, and the right to
recover for all past, present, and future infringements of the Trademarks;

                  (i) Any and all claims for damages by way of past, present and
future infringements of any of the rights included above, with the right, but
not the obligation, to sue for and collect such damages for said use or
infringement of the intellectual property rights identified above;

                  (j) All licenses or other rights to use any of the Copyrights,
Patents or Trademarks, and all license fees and royalties arising from such use
to the extent permitted by such license or rights;

                  (k) All amendments, extensions, renewals and extensions of
any of the Copyrights, Trademarks or Patents; and

                  (l) All proceeds and products of the foregoing, including
without limitation all payments under insurance or any indemnity or warranty
payable in respect of any of the foregoing.

THE INTEREST IN THE COLLATERAL BEING ASSIGNED HEREUNDER SHALL NOT BE CONSTRUED
AS A CURRENT ASSIGNMENT, BUT AS A CONTINGENT ASSIGNMENT TO SECURE THE NEW
SUBSIDIARY'S OBLIGATIONS TO ASSIGNEE.

         This Assignment secures the payment of all obligations of the New
Subsidiary now or hereafter existing under the Loan Agreement, including, but
not limited to, the Loans, the Notes, and all obligations, indebtedness and
liabilities of the New Subsidiary under this Assignment and each Letter of
Credit Agreement, Letter of Credit Security Agreement, the Assumption Agreement
and other Loan Document, and all other obligations, indebtedness and liabilities
of the New Subsidiary to Assignee, whether now existing or hereafter arising,
whether or not evidenced by notes or other instruments, and whether such
obligations, indebtedness and liabilities are direct or indirect, fixed or
contingent, liquidated or unliquidated, due or to become due, joint, several, or
joint and several (all such obligations of the New Subsidiary being the
"Obligations"). Without limiting the generality of the foregoing, this
 -----------
Assignment secures the payment of all amounts that constitute part of the
Obligations and would be owed by the New Subsidiary to Assignee but for the fact
that they are unenforceable or not allowable due to the existence of a
bankruptcy, reorganization or similar proceeding involving the New Subsidiary.

         2.       Authorization and Request.  The New Subsidiary authorizes and
                  --------------------------
requests that the Register of Copyrights and the Commissioner of Patents and
Trademarks record this conditional assignment.

         3.       Covenants and Warranties.  The New Subsidiary represents,
                  -------------------------
warrants, covenants and agrees as follows:


                                       3



<PAGE>

                  (a) The New Subsidiary is now the sole owner of its
Collateral, except for non-exclusive licenses granted by the New Subsidiary to
its Customers in the ordinary course of business.

                  (b) Listed on Exhibits A-1 and A-2 are all material Copyrights
owned by the New Subsidiary, in which the New Subsidiary has an interest
(excluding off-the-shelf licensed software and databases), or which are used in
the New Subsidiary's business. Listed on Exhibit A-3 are all material Licenses
pursuant to which the New Subsidiary has a right to use the Collateral, in which
the New Subsidiary has an interest (excluding off-the-shelf licensed software
and databases), or which are used in the New Subsidiary's business. Listed on
Exhibit B are all material Patents owned by the New Subsidiary, in which the New
Subsidiary has an interest, or which are licensed to the New Subsidiary for use
in the New Subsidiary's business. Listed on Exhibit C are all material
Trademarks owned by the New Subsidiary, in which the New Subsidiary has an
interest, or which are used in the New Subsidiary's business.

                  (c) Each employee, agent and/or independent contractor of the
New Subsidiary who has participated in the creation of the property constituting
the Collateral has either executed an assignment of his or her rights of
authorship to the New Subsidiary or is an employee of the New Subsidiary acting
within the scope of his or her employment and was such an employee at the time
of said creation.

                  (d) If required by Assignee after the occurrence of a Security
Event, all of the New Subsidiary's present and future Collateral (including,
without limitation, software, computer programs and other works of authorship)
subject or entitled to United States copyright, patent or trademark protection,
the sale, licensing or other disposition of which results in royalties
receivable, license fees receivable, accounts receivable or other sums owing to
the New Subsidiary (collectively, "Receivables"), shall be registered with the
                                   -----------
United States Copyright Office or the United States Patent and Trademark Office,
as applicable, and the New Subsidiary shall provide to Assignee copies of all
such registrations promptly upon the receipt of the same.

                  (e) The New Subsidiary shall undertake all reasonable measures
to cause its employees, agents and independent contractors to assign to the New
Subsidiary all rights of authorship to any copyrighted material in which the New
Subsidiary has or may subsequently acquire any right or interest.

                  (f) Performance of this Assignment does not conflict with or
result in a breach of any agreement to which the New Subsidiary is bound, except
to the extent that certain intellectual property agreements prohibit the
disclosure of information or the assignment of the rights thereunder to a third
party without the licensor's or other party's consent and this Assignment
constitutes an assignment or requires such disclosure.

                  (g) During the term of this Assignment, without the prior
written consent of Assignee, the New Subsidiary will not transfer or otherwise
encumber any interest in the Collateral, except for non-exclusive licenses
granted by the New Subsidiary in the ordinary course of business or as set forth
in this Assignment.

                  (h) Each part of the Collateral is valid and enforceable, and
no part of the Collateral has been judged invalid or unenforceable, in whole or
in part, and no claim has been made that any part of the Collateral violates the
rights of any third party.

                                       4



<PAGE>

                  (i) The New Subsidiary shall promptly advise Assignee of any
material change in the composition of the Collateral, including but not limited
to any subsequent ownership right of the New Subsidiary in or to any material
Trademark, Patent or Copyright not specified in this Assignment.

                  (j) The New Subsidiary shall (1) protect, defend and maintain
the validity and enforceability of the Trademarks, Patents and Copyrights,
subject to the New Subsidiary's reasonable business judgment as to the value of
the Trademark, Patent or Copyright, and the cost of such defense, (2) use
commercially reasonable efforts to detect infringements of the Trademarks,
Patents and Copyrights and promptly advise Assignee in writing of material
infringements detected, and (3) not allow any Trademarks, Patents, or Copyrights
to be abandoned, forfeited or dedicated to the public without the written
consent of Assignee, which shall not be unreasonably withheld, unless the New
Subsidiary determines that reasonable business practices suggest that
abandonment is appropriate.

                  (k) The New Subsidiary shall promptly register the most recent
version of any of its Copyrights, Trademarks or Patents, if not so already
registered, that are material to its business, and shall, from time to time,
execute and file such other instruments, and take such further actions as
Assignee may reasonably request from time to time to perfect or continue the
perfection of Assignee's interest in the Collateral.

                  (l) This Assignment creates, and in the case of after acquired
Collateral, this Assignment will create at the time the New Subsidiary first has
rights in such after acquired Collateral, in favor of Assignee a valid and
perfected first priority security interest in the Collateral in the United
States securing the payment and performance of the Obligations upon making the
filings referred to in clause (m) below.

                  (m) To its knowledge, except for, and upon, the filing with
the United States Patent and Trademark Office with respect to the Patents and
Trademarks and the Register of Copyrights with respect to the Copyrights
necessary to perfect the security interests and assignment created hereunder and
except as has been already made or obtained, no authorization, approval or other
action by, and no notice to or filing with, any U.S. governmental authority or
U.S. regulatory body is required either (1) for the grant by the New Subsidiary
of the security interest granted hereby or for the execution, delivery or
performance of this Assignment by the New Subsidiary in the U.S. or (2) for the
perfection in the United States or the exercise by Assignee of its rights and
remedies thereunder.

                  (n) All information heretofore, herein or hereafter supplied
to Assignee by or on behalf of the New Subsidiary with respect to the Collateral
is accurate and complete in all material respects.

                  (o) The New Subsidiary shall not enter into any agreement that
would materially impair or conflict with its obligations hereunder without
Assignee's prior written consent. The New Subsidiary shall not permit the
inclusion in any material contract to which it becomes a party of any provisions
that could or might in any way prevent the creation of a security interest in
its rights and interest in any property included within the definition of the
Collateral acquired under such contracts.

                                       5


<PAGE>

                  (p) Upon any executive officer of the New Subsidiary obtaining
actual knowledge thereof, the New Subsidiary will promptly notify Assignee in
writing of any event that materially adversely affects the value of any material
Collateral, the ability of the New Subsidiary to dispose of any material
Collateral or the rights and remedies of Assignee in relation thereto, including
the levy of any legal process against any of the Collateral.

         4. Assignee's Rights. Assignee shall have the right, but not the
            -----------------
obligation, to take, at the New Subsidiary's sole expense, any actions that the
New Subsidiary is required under this Assignment to take but which the New
Subsidiary fails to take, after fifteen (15) days' notice to the New Subsidiary.
The New Subsidiary shall reimburse and indemnify Assignee for all reasonable
costs and reasonable expenses incurred in the reasonable exercise of its rights
under this Section 4.

         5. Inspection Rights. The New Subsidiary hereby grants to Assignee and
            -----------------
its employees, representatives and agents the right to visit, during reasonable
hours upon prior reasonable written notice to the New Subsidiary, any of the New
Subsidiary's plants and facilities that manufacture, install or store products
(or that have done so during the prior six-month period) that are sold utilizing
any of the Collateral, and to inspect the products and quality control records
relating thereto upon reasonable written notice to the New Subsidiary and as
often as may be reasonably requested, but not more than one (1) in every six (6)
months.

         6. Further Assurances; Attorney in Fact.  The New Subsidiary
            ------------------------------------
represents, warrants, covenants and agrees as follows:

                  (a) The New Subsidiary will make, execute, acknowledge and
deliver, and file and record in the proper filing and recording places in the
United States, all such instruments, including, appropriate financing and
continuation statements and collateral agreements and filings with the United
States Patent and Trademark Office and the Register of Copyrights, and take all
such action as may reasonably be deemed necessary or advisable, or as requested
by Assignee, to perfect Assignee's security interest in all Copyrights, Patents
and Trademarks and otherwise to carry out the intent and purposes of this
Assignment, or for assuring and confirming to Assignee the grant or perfection
of a security interest in all Collateral.

                  (b) Upon an Event of Default, the New Subsidiary hereby
irrevocably appoints Assignee as its attorney-in-fact, with full authority in
the place and stead of the New Subsidiary and in the name of the New Subsidiary,
Assignee or otherwise, from time to time in Assignee's discretion, upon the New
Subsidiary's failure or inability to do so, to take any action and to execute
any instrument which Assignee may deem necessary or advisable to accomplish the
purposes of this Assignment, including:

                      (i) To modify, in its sole discretion, this Assignment
without first obtaining the New Subsidiary's approval of or signature to such
modification by amending Exhibit A-1, Exhibit A-2, Exhibit A-3, Exhibit B and
Exhibit C, thereof, as appropriate, to include reference to any right, title or
interest in any Copyrights, Patents or Trademarks acquired by the New Subsidiary
after the execution hereof or to delete any reference to any right, title or
interest in any Copyrights, Patents or Trademarks in which the New Subsidiary no
longer has or claims any right, title or interest; and

                                       6



<PAGE>

                      (ii) To file, in its sole discretion, one or more
financing or continuation statements and amendments thereto, relative to any of
the Collateral without the signature of the New Subsidiary where permitted by
law.

         7. Events of Default.  The occurrence of any of the following shall
            ------------------
constitute an Event of Default under the Assignment:


                  (a) An Event of Default occurs under the Loan Agreement; or

                  (b) The New Subsidiary breaches or fails to perform or observe
in any material respect any representation, warranty or agreement made by the
New Subsidiary in this Assignment.

         8. Remedies.  Upon the occurrence and continuance of an Event of
            ---------
Default, Assignee shall have the right to exercise all the remedies of a
secured party under the UCC, including without limitation, the right to:

                  (a) require the New Subsidiary to assemble any tangible
property in which the Collateral is embodied and in which Assignee has a
security interest and to make it available to Assignee at a place designated by
Assignee,

                  (b) exercise any and all rights as beneficial and legal owner
of the Collateral, including, without limitation, any and all consensual rights
and powers with respect to the Collateral, and

                  (c) sell or assign or grant a license to use, or cause to be
sold or assigned or grant a license to use any or all of the Collateral or any
part thereof, in each case, free of all rights and claims of the New Subsidiary
therein and thereto, except to the extent such actions would violate
restrictions against assignments contained in any Collateral in which the New
Subsidiary's rights arise by contract or license. In that connection, Assignee
shall have the right to cause any or all of the Collateral to be transferred of
record into the name of Assignee or its nominee and the right to impose (i) such
limitations and restrictions on the sale or assignment of the Collateral as
Assignee may deem to be necessary or appropriate to comply with any law, rule or
regulation having applicability to such sale or assignment and (ii) requirements
for any necessary governmental approvals. To the extent not inconsistent with
any license or contract under which the New Subsidiary's rights arise, Assignee
shall have a nonexclusive, royalty-free license to use the Copyrights, Patents
and Trademarks to the extent reasonably necessary to permit Assignee to exercise
its rights and remedies upon the occurrence of an Event of Default. The New
Subsidiary will pay any expenses (including reasonable attorney's fees) incurred
by Assignee in connection with the exercise of any of Assignee's rights
hereunder, including without limitation any expense incurred in disposing of the
Collateral. All of Assignee's rights and remedies with respect to the Collateral
shall be cumulative.

         9. Indemnity. The New Subsidiary agrees to defend, indemnify and hold
            ---------
harmless Assignee and its officers, employees, and agents against: (a) all
obligations, demands, claims, and liabilities claimed or asserted by any other
party in connection with the transactions contemplated by this Assignment, and
(b) all losses or expenses in any way suffered, incurred, or paid by Assignee as
a result of or in any way arising out of, following or consequential to
transactions between Assignee and the New Subsidiary, whether under this
Assignment or

                                       7


<PAGE>

otherwise (including without limitation, reasonable attorneys fees and
reasonable expenses), except for losses arising from or out of Assignee's gross
negligence or willful misconduct.

         10. Release. At such time as Assignors shall completely satisfy all of
             -------
the Obligations, Assignee shall execute and deliver to Assignors all assignments
and other instruments as may be reasonably necessary or proper to terminate
Assignee's security interest and any conditional assignment in the Collateral,
subject to any disposition of the Collateral which may have been made by
Assignee pursuant to this Assignment. For the purpose of this Assignment, the
Obligations shall be deemed to continue if any Assignor enters into any
bankruptcy or similar proceeding at a time when any amount paid to Assignee
could be ordered to be repaid as a preference or pursuant to a similar theory,
and shall continue until it is finally determined that no such repayment can be
ordered.

         11. No Waiver. No course of dealing between any Assignor and Assignee,
             ---------
nor any failure to exercise nor any delay in exercising, on the part of
Assignee, any right, power, or privilege under this Assignment or under the Loan
Agreement or any other agreement, shall operate as a waiver. No single or
partial exercise of any right, power, or privilege under this Assignment or
under the Loan Agreement or any other agreement by Assignee shall preclude any
other or further exercise of such right, power, or privilege or the exercise of
any other right, power, or privilege by Assignee.

         12. Rights Are Cumulative.  All of Assignee's rights and remedies with
             ---------------------
respect to the Collateral whether established by this Assignment, the Loan
Agreement, or any other documents or agreements, or by law shall be cumulative
and may be exercised concurrently or in any order.

         13. Course of Dealing.  No course of dealing, nor any failure to
             ------------------
exercise, nor any delay in exercising any right, power or privilege hereunder
shall operate as a waiver thereof.

         14. Attorneys' Fees.  If any action relating to this Assignment is
             ----------------
brought by either party hereto against the other party, the prevailing party
shall be entitled to recover reasonable attorneys fees, costs and disbursements.

         15. Amendments. This Assignment may be amended only by a written
             ----------
instrument signed by both parties hereto. To the extent that any provision of
this Assignment conflicts with any provision of the Loan Agreement, the
provision giving Assignee greater rights or remedies shall govern, it being
understood that the purpose of this Assignment is to add to, and not detract
from, the rights granted to Assignee under the Loan Agreement. This Assignment,
the Loan Agreement, and the documents relating thereto comprise the entire
agreement of the parties with respect to the matters addressed in this
Assignment.

         16. Severability. The provisions of this Assignment are severable. If
             ------------
any provision of this Assignment is held invalid or unenforceable in whole or in
part in any jurisdiction, then such invalidity or unenforceability shall affect
only such provision, or part thereof, in such jurisdiction, and shall not in any
manner affect such provision or part thereof in any other jurisdiction, or any
other provision of this Assignment in any jurisdiction.

         17. Counterparts.  This Assignment may be executed in two or more
             -------------
counterparts, each of which shall be deemed an original but all of which
together shall constitute the same instrument.


                                       8



<PAGE>


         18. Governing Law and Jurisdiction.  This Assignment shall be governed
             -------------------------------
by the laws of the Commonwealth of Virginia, without regard for choice of law
provisions.  The New Subsidiary and Assignee consent to the nonexclusive
jurisdiction of any state or federal court located in Fairfax County, Virginia.

         19. Confidentiality. In handling any confidential information, each of
             ---------------
Assignee and its agents shall exercise the same degree of care that its exercise
with respect to its own proprietary information of the same types to maintain
the confidentiality of any non-public information thereby received or received
pursuant to this Assignment except that the disclosure of this information may
be made (a) to the affiliates of Assignee, (b) to prospective transferee or
purchasers of an interest in the obligations secured hereby, provided that they
have entered into a comparable confidentiality agreement in favor of the New
Subsidiary and have delivered a copy to the New Subsidiary, (c) as required by
law, regulation, rule or order, subpoena judicial order or similar order and (d)
as may be required in connection with the examination, audit or similar
investigation of Assignee.

         20. WAIVER OF RIGHT TO JURY TRIAL. ASSIGNEE AND THE NEW SUBSIDIARY EACH
             -----------------------------
HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED UPON,
ARISING OUT OF, OR IN ANY WAY RELATING TO: (a) THIS ASSIGNMENT; OR (b) ANY OTHER
PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN ASSIGNEE AND THE NEW
SUBSIDIARY; OR (c) ANY CONDUCT, ACTS OR OMISSIONS OF ASSIGNEE OR THE NEW
SUBSIDIARY OR ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR
ANY OTHER PERSONS AFFILIATED WITH ASSIGNEE OR THE NEW SUBSIDIARY; IN EACH OF THE
FOREGOING CASES, WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

                         [SIGNATURES ON FOLLOWING PAGE]


                                       9


<PAGE>

         IN WITNESS WHEREOF, the parties hereto have executed this Assignment on
the day and year first above written.

                                            ASSIGNOR:
                                            --------

                                            THE MARASCO NEWTON GROUP LTD.,
                                            a Virginia corporation

Address of New Subsidiary:

                                            By:      /s/ Amy L. Marasco
                                                   ----------------------------
                                            Name:    Amy L. Marasco
                                                   ----------------------------
2801 Clarendon Boulevard, Suite 100         Title:   President
Arlington, Virginia  22201                         ----------------------------

                                            SRA INTERNATIONAL, INC., a Delaware
                                            corporation


                                            By:      /s/ Stephen C. Hughes
                                                   ----------------------------
                                            Name:    Stephen C. Hughes
                                                   ----------------------------
                                            Title:   President
                                                   ----------------------------

                                            ASSIGNEE:
                                            --------

                                            SUNTRUST BANK, a Georgia banking
                                            corporation
Address of Assignee:

                                            By:
1445 New York Avenue, N.W.                         ----------------------------
Washington, D.C.  20005                     Name:
                                                   ----------------------------
                                            Title:
                                                   ----------------------------



                                       10


<PAGE>

         State OF Virginia )

         COUNTY OF Fairfax)

         On April 15, 2002, before me, Deborah Cioletti, Notary Public,
personally appeared Amy L. Marasco personally known to me (or proved to me on
the basis of satisfactory evidence) to be the person(s) whose name(s) is/are
subscribed to the within instrument and acknowledged to me that he/she/they
executed the same in his/her/their authorized capacity(ies), and that by
his/her/their signature(s) on the instrument the person(s), or the entity upon
behalf of which the person(s) acted, executed the instrument.

         Witness my hand and official seal.

                                                /s/ Deborah Cioletti
                                                ---------------------------
                                                Notary Public

(Seal)                                          My Commission Expires 11-30-04


         STATE OF VIRGINIA                  )

         COUNTY OF FAIRFAX                  )

         On April 17, 2002, before me, Deborah Cioletti

                                         , Notary Public, personally appeared
-----------------------------------------
Stephen C. Hughes                                                            ,
                  -----------------------------------------------------------
personally known to me (or proved to me on the basis of satisfactory evidence)
to be the person(s) whose name(s) is/are subscribed to the within instrument
and acknowledged to me that he/she/they executed the same in his/her/their
authorized capacity(ies), and that by his/her/their signature(s) on the
instrument the person(s), or the entity upon behalf of which the person(s)
acted, executed the instrument.

         Witness my hand and official seal.

                                                /s/ Deborah Cioletti
                                                ---------------------------
                                                Notary Public

(Seal)                                          My Commission Expires 11-30-04






                                       11



<PAGE>

                                  EXHIBIT "A-1"

                              REGISTERED COPYRIGHTS

REG. NO.                         REG. DATE                         COPYRIGHT
--------                         ---------                         ---------



                                      None



<PAGE>

                                  EXHIBIT "A-2"

                               UNREGISTERED RIGHTS

                                      None



<PAGE>

                                  EXHIBIT "A-3"

                   DESCRIPTION OF COPYRIGHT LICENSE AGREEMENTS
                   -------------------------------------------

                                      None



<PAGE>

                                   EXHIBIT "B"

                                     PATENTS



DOCKET NO.        COUNTRY       SERIAL NO.         FILING DATE           STATUS
----------        -------      ----------          -----------           ------




                                      None



<PAGE>

                                   EXHIBIT "C"

                                   TRADEMARKS




MARK            COUNTRY                   SERIAL NO.                   STATUS
----            -------                   ----------                   ------






                                      None