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                                                                   Exhibit 10.36

                    AMENDMENT TO PURCHASE AND SALE AGREEMENT

     THIS AMENDMENT TO PURCHASE AND SALE AGREEMENT (the "Amendment") is made and
entered into this 28th day of December, 2005 by and between Dynamics Research
Corporation, a Massachusetts corporation ("Seller") and Direct Invest Property
Acquisition, L.L.C., a Delaware limited liability company ("Buyer").

                                    RECITALS

     A. Seller and Buyer entered into that certain Purchase and Sale Agreement,
dated November 18, 2005 (the "Agreement"), regarding the sale of certain real
property located at 60 Frontage Road, Andover, Massachusetts, and more
particularly described in the Agreement; and

     B. Seller and Buyer desire to extend and restate the closing date of the
transaction contemplated under the Agreement and to acknowledge the assignment
of Buyer's right, title and interest to and under the Agreement to Direct Invest
- 60 Frontage, LLC ("Assignee").

                                    AGREEMENT

     NOW, THEREFORE, in consideration of the foregoing, of the mutual promises
set forth herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto, intending
legally to be bound, hereby covenant and agree to amend and modify the
Agreement, as follows:

     1. RECITALS; DEFINED TERMS. The foregoing Recitals are hereby incorporated
by this reference and made a substantive part hereof. Any capitalized terms not
otherwise defined herein shall have the meaning set forth in the Agreement.

     2. AMENDMENT. Seller and Buyer hereby agree to change the Closing Date from
December 19, 2005 to December 28, 2005 and Section 7(a) of the Agreement is
hereby amended by deleting the second (2nd) and third (3rd) sentences of Section
7(a) and substituting the following in lieu thereof:

          "The "CLOSING DATE" shall be December 28, 2005."

     3. ASSIGNMENT TO ASSIGNEE. Seller and Buyer hereby agree that Buyer has
assigned and Assignee has assumed Buyer's right, title and interest to and under
the Agreement. At the Closing, Seller shall comply with Seller's obligations
under the Agreement and Assignee shall comply with Buyer's obligations under the
Agreement.

     4. BINDING EFFECT. This Amendment shall be binding upon, and shall inure to
the benefit of, the parties hereto and their respective successors and assigns,
including but not limited to Assignee.

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     5. CONFLICTS. In the event any provision of this Amendment conflicts with a
provision of the Agreement, such provision of this Amendment shall govern and
control for all purposes and in all respects.

     6. RATIFICATION. Except as expressly modified hereby, the Agreement remains
unmodified and in full force and effect, and the Agreement is hereby ratified
and confirmed for all purposes and in all respects.

     7. COUNTERPARTS. This Amendment may be executed in multiple counterpart
copies, all of which constitute a single document, and may be delivered by
facsimile transmission.

                      [Signatures Appear on Following Page]

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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment to
Purchase and Sale Agreement as of the date first above written.

                                        SELLER:

                                        DYNAMICS RESEARCH CORPORATION,
                                        a Massachusetts corporation


                                        By: /s/ James P. Regan
                                            ------------------------------------
                                        Name: James P. Regan
                                        Title: President


                                        BUYER:

                                        DIRECT INVEST PROPERTY ACQUISITION,
                                        L.L.C., a Delaware limited liability
                                        company


                                        By: /s/ William F. Rand, III
                                            ------------------------------------
                                        Name: William F. Rand, III
                                              ----------------------------------
                                        Title: Manager
                                               ---------------------------------

           Signature Page to Amendment to Purchase and Sale Agreement

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ACKNOWLEDGED:

ASSIGNEE:

DIRECT INVEST - 60 FRONTAGE, LLC,
a Delaware limited liability company


By: /s/ Robert Licht
    ---------------------------------
Name: Robert Licht
      -------------------------------
Title: Authorized Signatory
       ------------------------------

           Signature Page to Amendment to Purchase and Sale Agreement