**Exhibit****2.4****AMENDMENT TO STOCK PURCHASE AGREEMENT**     THIS **AMENDMENT TO STOCK PURCHASE AGREEMENT**(this “Amendment”) is effective as ofJanuary 30, 2007, by and among (i) SM&A, a Delaware corporation (“Buyer”), (ii) ProjectPlanning, Incorporated, a Massachusetts corporation (the “Company”), and (iii) Richard Bowe(the “Shareholder”).  Buyer, the Company, and the Shareholder are sometimes individuallyreferred to as a “Party,” and collectively as the “Parties.” All initially capitalized terms usedbut not defined in this Amendment shall have the meanings assigned to them in the Stock PurchaseAgreement (as defined below).**RECITALS**     **WHEREAS**, on January 30, 2007, the Parties entered into a Stock Purchase Agreement, pursuant towhich Buyer acquired from the Shareholder all of the issued and outstanding capital stock of theCompany (the “Shares”), for total consideration valued at approximately $6.7 million,including $4.5 million in cash (the “Stock Purchase Agreement”);     **WHEREAS**, Section 1.7 of the Stock Purchase Agreement, as originally executed, states that theShareholder was entitled to receive additional consideration (“Earn-Out Consideration”) forthe Shares based on: (i) the employment of Richard Bowe (“Bowe”) by the Company or theBuyer and (ii) the Annual Revenue of the Buyer during each of the three consecutive twelve-monthperiods following the Closing Date;     **WHEREAS**, it was the intent and agreement of the Parties at the time that the Stock PurchaseAgreement was entered into that the Earn-Out Consideration be based solely upon Annual Revenue andnot on the employment of Bowe;     **WHEREAS**, the parties desire to amend the Stock Purchase Agreement in order to correct certainprovisions therein to accurately reflect their intent and agreement with respect to the payment ofthe Earn-Out Consideration;     **NOW THEREFORE**, in consideration of the above recitals, and of the mutual covenants containedherein, and other good and valuable consideration, the receipt and adequacy of which are herebyacknowledged by the parties hereto, the parties agree as follows:**AGREEMENT**     1. Amendments to the Stock Purchase Agreement.          (a) Section 1.7(c) (including the subsections thereof) shall be deleted in its entirety andreplaced with the phrase “[Intentionally deleted.]”
 

 
          (b) The introductory clause of Section 1.7(d) shall be amended in its entirety to read asfollows: “For purposes of calculating the Earn-Out Consideration, the following terms shall havethe following meanings:”     2. No Other Provisions Amended. All other provisions of the Stock Purchase Agreementnot specifically amended by this Amendment shall remain in full force and effect.     3. Severability. If any term, provision, covenant or restriction of this Amendment isheld by a court of competent jurisdiction to be invalid, void or unenforceable, the remainder ofthe terms, provisions, covenants and restrictions of this Amendment shall remain in full force andeffect and shall in no way be affected, impaired or invalidated.     4. Counterparts. This Amendment may be executed in one or more counterparts, each ofwhich shall be deemed to be an original, but all of which shall constitute one and the sameagreement.     5. Governing Law. This Amendment shall be deemed to be made in and in all respectsshall be interpreted, construed and governed by and in accordance with the laws of the State ofDelaware without regard to the conflict of law principles thereof.*[Signature Page Follows]*
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          IN WITNESS WHEREOF, each of the Parties has duly executed this Amendment, or caused thisAmendment to be duly executed on its behalf, as of this 8 day of May, 2008.         “BUYER”:           SM&A,