**Exhibit 10.10**

**AMENDEDAND RESTATED EXECUTIVE EMPLOYMENT AGREEMENT**

THIS AMENDED AND RESTATEDEXECUTIVE EMPLOYMENT AGREEMENT (this “Agreement”) is made effective asof June 22, 2007 by and between SI INTERNATIONAL, INC., a Delaware corporation(the “Company”), and S. BRADFORD ANTLE****(the “Executive”).

WHEREAS, the Executiveand the Company are parties to an Executive Employment Agreement, dated as ofJuly 24, 2002 (the “Original Agreement”);

WHEREAS, the Board ofDirectors of the Company (the “Board”), by and through its CompensationCommittee, desires to amend the nature and amount of compensation and otherbenefits to be provided to the Executive and any of the rights of the Executivein the event of his termination of employment with the Company;

WHEREAS, the Executive iswilling to continue to serve the Company on the terms and conditions hereinprovided; and

WHEREAS, in order toeffect the foregoing, the Company and the Executive wish to enter into thisAgreement under the terms and conditions set forth below.

NOW, THEREFORE, inconsideration of the foregoing, of the mutual promises and the respectivecovenants and agreements of the parties herein contained, the parties intendingto be legally bound, agree as follows:

# 1.             Employment.  The Company hereby agrees to employ theExecutive, and the Executive hereby agrees to serve the Company, on the termsand conditions set forth herein.

# 2.             Term.  The Executive’s employment pursuant to thisAgreement shall continue in effect through July 1, 2008; provided, however,that commencing on July 1, 2008 and each July 1st thereafter, the Executive’semployment pursuant to this Agreement shall automatically be extended foradditional one (1) year terms unless, not later than ninety (90) calendar daysprior to such date, the Company or the Executive shall have given writtennotice that such party does not wish to extend the Executive’s employmentpursuant to this Agreement; and provided, further, that if a Change of Control(as defined herein) of the Company shall have occurred during the original orany extended term of the Executive’s employment pursuant to this Agreement, theterm of the Executive’s employment pursuant to this Agreement shall continue ineffect for a period of twelve (12) months beyond the month in which such Changeof Control occurred.

# 3.             Position and Duties.  During the Executive’s employment with theCompany pursuant to this Agreement, (i) the Executive shall serve as thePresident and Chief Executive Officer of the Company and shall have suchresponsibilities and authority as is customary for a Chief Executive Officer ofa company of similar size and nature as the Company, and (ii) the Executiveshall serve as a Director on the Board of Directors of the Company.

# 4.             Compensation, Benefits andRelated Matters.

## (a)           Base Salary. During the Executive’s employment with the Company pursuant to thisAgreement, the Company shall pay to the Executive a salary at an initial rateof

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## Four Hundred Seventy Thousand Dollars($470,000) per annum in equal installmentsas nearly as practicable on the normal payroll periods for employees of theCompany generally (the “Base Salary”). The Base Salary may be increased from time to time at the discretion ofthe Board.

## (b)           Performance-Based Bonus.  During the Executive’s employment with theCompany pursuant to this Agreement, the Executive shall be eligible to receivea bonus following the end of each fiscal year in accordance with theperformance-based bonus plans established by the Board for senior executiveofficers from time to time after taking into account the performance of theCompany and the Executive and such other facts and circumstances as the Boardmay deem appropriate to consider.

## (c)           Expenses. During the Executive’s employment with the Company pursuant to thisAgreement, the Executive shall be entitled to receive prompt reimbursement forall reasonable expenses incurred by the Executive in performing serviceshereunder, including, without limitation, all expenses for travel, all livingexpenses while away from home on business or at the request of and in theservice of the Company, and all reasonable entertainment expenses.

## (d)           Benefits.  During the Executive’s employment with theCompany pursuant to this Agreement, the Executive shall be entitled toparticipate in all of the employee benefit plans and arrangements generallyprovided from time to time to senior executive officers of the Company.  The Company may initiate, change anddiscontinue any such plan or arrangement at any time.  Nothing paid to the Executive under any planor arrangement presently in effect or made available in the future shall bedeemed to be in lieu of any amounts payable to the Executive pursuant to this Section4.

## (e)   CompensationDuring Incapacity.  During theExecutive’s employment with the Company pursuant to this Agreement, for anyperiod that the Executive fails to perform the Executive’s full-time dutieswith the Company as a result of incapacity due to physical or mental illness,the Company shall pay the Executive’s Base Salary to the Executive at the ratein effect at the commencement of any such period, together with allcompensation and benefits payable to the Executive under the terms of anycompensation or benefit plan, program or arrangement maintained by the Companyduring such period, until the Executive’s employment is terminated by theCompany for Disability.

# 5.             Termination.

## (a)           TheExecutive’s employment with the Company may be terminated by the Company (i) atany time for Cause or without Cause; or (ii) if, as a result of the Executive’sincapacity due to physical or mental illness, the Executive shall have beenabsent from the full-time performance of the Executive’s duties with theCompany for three (3) consecutive months (a “Disability”).  The Executive’s employment with the Companyshall be terminated immediately upon the death of the Executive.  The Executive’s employment with the Companymay be terminated at any time by the Executive for Constructive Termination orwithout Constructive Termination.

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## (b)           Anypurported termination of the Executive’s employment by the Company or theExecutive (other than by reason of death) shall be communicated by writtenNotice of Termination from one party hereto to the other in accordance with Section19 hereof.

## (c)           Asused herein:

(i)            A “Noticeof Termination” shall mean a notice that specifies the Date of Terminationand that, in the case of a termination by the Executive, shall indicate thespecific termination provision in this Agreement relied upon and shall setforth in reasonable detail the facts and circumstances claimed to provide abasis for termination of the Executive’s employment under the provision soindicated and that, in the case of a termination by the Company, shall indicatewhether such termination is for Cause or without Cause.

(ii)           The“Date of Termination” with respect to any purported termination of theExecutive’s employment shall mean (A) if the Executive’s employment isterminated for Disability, thirty (30) days after Notice of Termination isgiven (provided that the Executive shall not have returned to the full-timeperformance of the Executive’s duties during such thirty (30) day period), (B)if the Executive’s employment is terminated by reason of death, then the datethereof, (C) if the Executive’s employment is terminated pursuant to Section2 hereof, the date on which the Executive’s employment expires pursuant tosuch section, and (D) if the Executive’s employment is terminated for any otherreason, the date specified in the Notice of Termination (which, in the case ofa termination by the Executive, shall not be less than thirty (30) nor morethan sixty (60) days from the date such Notice of Termination is given).

# 6.             SeverancePayments.

## (a)           The Company shall pay the Executive the payments and benefitsset forth in this Section 6(a) upon any termination of the Executive’semployment, including, without limitation, the nonextension of the Executive’semployment by the Company pursuant to Section 2 hereof, unless suchtermination is by the Company for Cause, by the Executive without ConstructiveTermination or the nonextension of the Executive’s employment by the Executivepursuant to Section 2 hereof:

(i)            TheCompany shall pay as severance pay to the Executive an amount (the “CashSeverance Amount”) equal to two (2) times the sum of (x) the Executive’sBase Salary at the highest rate in effect prior to the Date of Termination,plus (y) the full amount of the target level bonus for which the Executive iseligible (or, if no such target level bonus exists, the maximum bonus,performance and incentive compensation amounts for which the Executive iseligible), calculated based upon the bonus period in which the Date ofTermination occurs and annualized to the extent that such bonus period does notreflect a twelve (12) month period.  TheCompany shall pay the Cash Severance Amount over the twenty-four (24) monthperiod immediately following the Date of Termination (the “Severance Period”),in equal installments as nearly as practicable, on the normal payroll dates foremployees of the Company generally; providedthat, in the eventthe aggregate portion of the Cash Severance Amount payable during the first six(6) months of the Severance Period would exceed an amount (the “MinimumAmount”) equal to two (2) times the lesser of (i) the Executive’sannualized compensation as in effect for the calendar year immediatelypreceding the calendar year during

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whichthe Executive’s termination of employment occurs, or (ii) the maximum amountthat may be taken into account under a qualified plan pursuant to Section401(a)(17) of the Internal Revenue Code of 1986, as amended (the “Code”)for the calendar year during which the Executive’s termination of employmentoccurs, then (x) the Company shall pay a portion of the Cash Severance Amountequal to the Minimum Amount over the first six (6) months of the SeverancePeriod, in equal installments as nearly as practicable, on the normal payrolldates for employees of the Company generally and (y) the Company shall pay theremainder of the Cash Severance Amount over the remaining eighteen (18) monthsof the Severance Period, in equal installments as nearly as practicable, on thenormal payroll dates for employees of the Company generally.  Notwithstanding the foregoing, in the eventthe Company terminates the Executive’s employment without Cause or elects notto extend the Executive’s employment pursuant to Section 2 hereof or theExecutive resigns after a Constructive Termination during the time periodcommencing with a written agreement for a Change of Control (which transactionis ultimately consummated) and ending two (2) years thereafter, the Companyshall pay the Cash Severance Amount in cash in a single lump sum payment withinfive (5) days of the Date of Termination; providedthat, in theevent the Cash Severance Amount would exceed the Minimum Amount (as definedabove), then a portion of the Cash Severance Amount equal to the Minimum Amountshall be paid no later than five (5) days after the Date of Termination, andthe remainder of the Cash Severance Amount shall be paid on the date that isone business day after the date that is six (6) months after the Date ofTermination.  In no event shall anypayments under this Section 6(a)(i) be made later than December 31 of the second(2nd) calendar year following the calendar year during which the Date ofTermination occurs.

### (ii)           Fora twenty-four (24) month period after the Date of Termination, the Companyshall administer and pay for the Executive’s life, disability, accident andhealth insurance benefits substantially similar to those which the Executive isreceiving immediately prior to the Notice of Termination.

## (b)           Notwithstandingany contrary provision in any agreement relating to the grant by the Company orany of its affiliates of any option to acquire shares of the Company’s or anyaffiliate’s capital stock pursuant to such entity’s stock option plans (“StockOptions”) or the issuance of capital stock or other equity interests of anysuch entity pursuant to a restricted stock agreement or similar arrangement (“RestrictedStock”) (including in each case, without limitation, Stock Options andRestricted Stock granted under the Company’s Amended and Restated Omnibus 2002Stock Incentive Plan (the “Plan”)), if such Stock Options or RestrictedStock held by the Executive are assumed or an equivalent option rightsubstituted by a successor corporation (or its affiliate) in a CorporateTransaction (as defined in the Notice of Stock Option Grant or Notice ofRestricted Stock Bonus Award entered into under the Plan) or a Change ofControl (as defined below), then during the period commencing with a writtenagreement for such Corporate Transaction or Change of Control (whichtransaction is ultimately consummated) and ending two (2) years thereafter theCompany terminates the Executive’s employment without Cause or elects not toextend the Executive’s employment pursuant to Section 2 hereof or the Executiveresigns after a Constructive Termination, all Stock Options and all shares ofRestricted Stock which have not yet become vested shall become vested in fullon the Date of Termination.  StockOptions and Restricted Stock not so assumed or substituted by the successorcorporation in such Corporate Transaction shall be treated as provided in thePlan or the agreements thereunder

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## (or other plans and agreements applicable to such Stock Options orRestricted Stock, as the case may be) with respect to Stock Options andRestricted Stock that are not assumed or substituted in such Corporate Transactionor Change of Control.

(c)           The payments provided in Section6(a) shall be in addition to the payments and benefits set forth in Section7 hereof.

# 7.             Compensation Other thanSeverance Payments.  If the Executive’semployment shall be terminated by him or the Company for any reason, theCompany shall (i) pay the Executive’s normal post-termination compensation andbenefits under, and in accordance with, the Company’s retirement, insurance andother compensation or benefit plans or programs during such period, (ii) pay the Executive, no later than five (5)days after the Date of Termination, an amount in cash equal to (A) theExecutive’s accrued but unpaid Base Salary through the Date of Termination,plus (B) the amount of any unpaid bonus, performance and incentive compensationwhich has been earned by the Executive for any fiscal period preceding the Dateof Termination in respect of which such compensation is paid or payable.

# 8.             Certain Definitions.

(a)           Cause.  “Cause” shall mean the following:

(i)            A good faith finding by the Boardthat the Executive (w) has been convicted of a felony, (x) has beenconvicted of a misdemeanor (excluding traffic violations) to the extent suchconviction could reasonably be considered to compromise the best interests ofthe Company or any of its Subsidiaries or render the Executive unfit or unableto perform his services and duties hereunder, (y) has committed any otheract or omission involving dishonesty, disloyalty or fraud with respect to theCompany or any of its Subsidiaries or any of their customers or suppliers, or(z) has committed an act involving unlawful or disreputable conduct in thecontext of Executive’s employment which is likely to be harmful to the Companyor its reputation;

(ii)           The continued failure by theExecutive to perform his duties in all material respects for the Company or anyof its Subsidiaries continuing for a period of 45 days following a demand forsuch performance by the Board or a material breach by the Executive of hisobligations under this Agreement continuing uncured (if curable) for a periodof 45 days following notice from the Board (other than any such failure orbreach resulting from the Executive’s incapacity due to physical or mentalillness), which demand shall identify in reasonable detail the manner that thatExecutive has not performed his duties or has breached his obligations (asapplicable) and give the Executive an opportunity to respond.  The foregoing shall not be construed to includethe Executive’s failure to achieve financial or operating objectives and goalsestablished by the Board; or

(iii)          A good faith finding by the Board thatthe Executive engaged in (x) misconduct materially injurious to the Company orany of its Subsidiaries or their reputation or (y) gross negligence or willfulmisconduct which has a material adverse effect on the Company or any of itsSubsidiaries.

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## (b)           Changeof Control.  A “Change of Control”shall be deemed to occur if (i) there shall be consummated (x) anyconsolidation or merger of the Company in which the Company is not thecontinuing or surviving corporation or pursuant to which shares of the Company’sCommon Stock would be converted into cash, securities or other property, otherthan a merger of the Company in which the holders of the Company’s Common Stockimmediately prior to the merger hold more than fifty percent (50%) of thevoting power of the surviving corporation immediately after the merger, or (y)any sale, lease, exchange or other transfer (in one transaction or a series of relatedtransactions) of all, or substantially all, of the assets of the Company, or(ii) the stockholders of the Company shall approve any plan or proposal forliquidation or dissolution of the Company, or (iii) any person (as such term isused in Section 13(d) and 14(d)(2) of the Securities Exchange Act of 1934, asamended (the “Exchange Act”)) shall become the beneficial owner (within the meaning of Rule 13d-3under the Exchange Act) of fifty percent (50%) or more of the Company’soutstanding Common Stock other than pursuant to a plan or arrangement enteredinto by such person and the Company, or (iv) within any twenty-four (24) monthperiod, the following individuals cease for any reason to constitute a majorityof the number of directors then serving on the Board: individuals who, on thedate hereof, constitute the Board and any new director (other than a directorwhose initial assumption of office is in connection with an actual orthreatened election contest, including but not limited to a consent solicitationrelating to the election of directors of the Company) whose appointment orelection by the Board or nomination for election by the Company’s shareholderswas approved or recommended by a vote of at least two-thirds (2/3) of thedirectors then still in office who either were directors on the date hereof orwhose appointment, election or nomination for election was previously soapproved or recommended.

## (c)           CommonStock.  “Common Stock” shallmean the Company’s Common Stock, par value $0.01 per share.

## (d)           ConstructiveTermination.  “ConstructiveTermination” shall mean the occurrence, without the Executive’s writtenconsent, of any of the following circumstances unless such circumstances arefully corrected prior to the Date of Termination specified in the Notice ofTermination given in respect thereof:

### (i)            Theassignment to the Executive of any duties materially inconsistent with theExecutive’s position, authority, duties or responsibilities (including status,offices, effective titles and reporting structures) in effect immediately priorto such assignment, or any other action by the Company which results in thematerial diminishment of such position, authority, duties or status as ChiefExecutive Officer of the Company or a substantial adverse alteration in thenature or status of the Executive’s responsibilities;

### (ii)           Therelocation of the Executive’s principal place of employment to a locationoutside of the Washington, D.C. metropolitan area or the Company’s requiringthe Executive to be based anywhere other than such principal place ofemployment (or permitted relocation thereof) except for required travel on theCompany’s business to an extent substantially consistent with the Executive’spresent business travel obligations; or

### (iii)          Amaterial breach of this Agreement by the Company (which shall in any eventinclude, without limitation, the failure by the Company to pay to the Executiveany

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### portion of the Executive’s then Base Salary or allocated bonus,incentive or other form of compensation or to pay to the Executive any portionof an installment of deferred compensation under any deferred compensationprogram of the Company, within seven (7) days of the date such compensation isdue, and any reduction in the Base Salary).

The Executive’s rightto terminate the Executive’s employment as a result of Constructive Terminationshall not be affected by the Executive’s incapacity due to physical or mentalillness.  The Executive’s termination ofemployment shall not be considered to be for Constructive Termination unless the Executive first provides writtennotice to the Company within ninety (90) days following the effective date ofsuch event, and the Company has been provided a period of at least thirty (30)days after receipt of the Executive’s notice during which to rescind orotherwise remedy the actions, events, or circumstances described in theExecutive’s notice.

(e)           Subsidiary.  “Subsidiary” shall meanany corporation of which the Company owns securities having a majority of theordinary voting power in electing the board of directors directly or throughone or more subsidiaries.

# 9.             D&OInsurance; Indemnification.

## (a)           Tothe fullest extent permitted by applicable law, the Company shall indemnify theExecutive against all expenses (including reasonable attorneys’ fees),judgments, fines, and amounts paid in settlement, as actually and reasonablyincurred by the Executive in connection with any threatened or pending action,suit, or proceeding, whether civil, criminal, administrative, or investigativethat the Executive is made a party to by reason of the fact that he is or wasperforming services as an officer or director of the Company.  Such indemnification shall continue as to theExecutive even if he has ceased to be an employee, officer, or director of theCompany and shall inure to the benefit of his heirs and estate.

## (b)           Anycosts, fees or expenses incurred by the Executive relating to indemnificationunder the Company’s Certificate of Incorporation, as amended, or the Company’sBylaws, as amended, shall be paid by the Company in advance as soon aspracticable but not later than three business days after receipt of writtenrequest of the Executive; provided that the Executive shall undertake to repaysuch amount to the extent that it is ultimately determined by a court ofcompetent jurisdiction that the Executive is not entitled toindemnification.  Subject to applicablelaw, the Executive’s right to indemnification or advances from the Companyshall be enforceable by the Executive in any court of competentjurisdiction.  The burden of proving thatindemnification or advances are not appropriate shall be on the Company.

# (c)           The provisions of this Section 9are in addition to, and not in derogation of, the indemnification provisions ofthe Company’s Certificate of Incorporation, as amended, the Company’s Bylaws,as amended, and the Indemnification Agreement between the Company and theExecutive (the “Indemnification Agreement”).

# 10.           No Mitigation.  The Company agrees that, if the Executive’semployment is terminated hereunder, the Executive is not required to seek otheremployment or to attempt in any way to reduce any amounts payable to theExecutive by the Company.  Furthermore,the

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# amount of any paymentprovided hereunder shall not be reduced by any compensation earned by theExecutive.

# 11.           Confidential Information.  The Executive acknowledges that theinformation, observations and data obtained by him while employed by theCompany or any Subsidiary (including those obtained prior to the date of thisAgreement concerning the business or affairs of the Company, or any of itsSubsidiaries (collectively, “Confidential Information”)) are theproperty of the Company and such Subsidiaries. Therefore, the Executive agrees that he shall not (during his employmentwith the Company or at any time thereafter) disclose to any unauthorized personor use for his own purposes any Confidential Information without the expressprior written consent of the Board, unless and to the extent that the aforementionedmatters: (a) become generally known to and available for use by the publicother than as a result of the Executive’s acts or omissions or (b) are requiredto be disclosed by judicial process or law. The Executive shall deliver to the Company at the termination of hisemployment, or at any other time the Company may request, all memoranda, notes,plans, records, reports, computer tapes, printouts and software and otherdocuments and data (and copies thereof) relating to the ConfidentialInformation, Work Product (as defined below) or the business of the Company orany Subsidiary which he may then possess or have under his control.

# 12.           Inventions and Patents.  The Executive hereby assigns to the Companyall right,-title and interest to all patents and patent applications, allinventions, innovations, improvements, developments, methods, designs,analyses, drawings, reports and all similar or related information (in eachcase whether or not patentable), all copyrights and copyrightable works, alltrade secrets, confidential information and know-how, and all otherintellectual property rights that are conceived, reduced to practice, developedor made by the Executive while employed by the Company and its Subsidiaries andthat (i) relate to the Company’s or any Subsidiary’s actual or anticipatedbusiness, research and development or existing or future products or services;or (ii) are conceived, reduced to practice, developed or made using anymaterial equipment, supplies, facilities, assets or resources of the Company orany Subsidiary (including but not limited to any intellectual property rights)(“Work Product”).  The Executiveshall promptly disclose such Work Product to the Board and perform all actionsreasonably requested by the Board (whether during his employment with theCompany or at any time thereafter) to establish and confirm the Company’sownership (including, without limitation, assignments, consents, powers ofattorney, applications and other instruments).

# 13.           Noncompetition.  In further consideration of the compensationto be paid to the Executive hereunder, the Executive acknowledges that in thecourse of his employment with the Company he has become and shall becomefamiliar with the Company’s trade secrets and with other Confidential Informationconcerning the Company and its Subsidiaries and that his services have been andshall be of special, unique and extraordinary value to the Company and itsSubsidiaries.  Therefore, the Executiveagrees that, during the Executive’s employment with the Company and for six (6)months thereafter (collectively the “Noncompete Period”), he shall not,without prior express written consent of the Board, directly or indirectly(whether for compensation or otherwise) own or hold any interest in, manage,operate, control, participate in, consult with, render services for, or in anymanner participate in any business engaged in any of the businesses or servicesprovided by the Company or its Subsidiaries during the employment with theCompany or the Noncompete Period (a “Competing Company”) or otherwisecompeting

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# with the businesses ofthe Company or its Subsidiaries, either as a general or limited partner,proprietor, common or preferred shareholder, officer, director, agent,employee, consultant, trustee, affiliate or otherwise.  The Executive acknowledges that the Company’sand its affiliates’ businesses are conducted nationally and internationally andagrees that the provisions in this Section 13 shall operate throughoutthe United States and the world.  Nothingherein shall prohibit the Executive from being a passive owner of not more thanfive percent (5%) of the outstanding securities of any publicly traded companythat constitutes a Competing Company, so long as the Executive has no activeparticipation in the business of such company.

# 14.           Non-Solicitation.  During the Executive’s employment with theCompany and for twelve (12) months thereafter (collectively the “NonsolicitPeriod”), the Executive shall not directly or indirectly through anotherentity (i) induce or attempt to induce any employee of the Company or anySubsidiary to leave the employ of the Company or such Subsidiary, or in any wayinterfere with the relationship between the Company or any Subsidiary and anyemployee thereof, (ii) hire any person who was an employee of the Company orany Subsidiary at any time during the twenty-four (24) months preceding theDate of Termination of the Executive, or (iii) induce or attempt to induceany customer, developer, client, member, supplier, licensee, licensor,franchisee or other business relation of the Company or any Subsidiary to ceasedoing business with the Company or such Subsidiary, or in any way interferewith the relationship between any such customer, developer, client, member,supplier, licensee or business relation and the Company or any Subsidiary(including, without limitation, making any negative statements orcommunications about the Company or any Subsidiary).

# 15.           Enforcement.  If, at the time of enforcement of any of Sections11 through 14, a court shall hold that the duration, scope or arearestrictions stated herein are unreasonable under circumstances then existing,the parties agree that the maximum duration, scope or area reasonable undersuch circumstances shall be substituted for the stated duration, scope or areaand that the court shall be allowed to revise the restrictions contained hereinto cover the maximum period, scope and area permitted by law.  Because the Executive’s services are uniqueand because he has access to Confidential Information and Work Product, theparties hereto acknowledge and agree that money damages would not be anadequate remedy for any breach of this Agreement.  Therefore, in the event of a breach orthreatened breach of this Agreement, the Company or its successors or assignsmay, in addition to other rights and remedies existing in their favor, apply toany court of competent jurisdiction for specific performance and/or injunctiveor other relief in order to enforce or prevent any violations of the provisionshereof (without posting a bond or other security).  In addition, in the event of an allegedbreach or violation by the Executive of any of Sections 11 through 14,the Noncompete Period and the Nonsolicit Period shall be tolled until suchbreach or violation has been duly cured. The Executive agrees that the restrictions contained in Sections 11through 14 are reasonable.

# 16.           Successors; Binding Agreement.

## (a)           Successors.  The Company will require any successor(whether direct or indirect, by purchase, merger, consolidation or otherwise)to all or substantially all of the business and/or assets of the Company, byagreement in form and substance reasonably satisfactory to the Executive, toexpressly assume and agree to perform this Agreement in the same manner and tothe same extent that the Company would be required to perform it if no such

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## succession had taken place.  Asused in this Agreement, “Company” shall mean the Company as hereinbeforedefined and any successor to its business and/or assets as aforesaid whichexecutes and delivers the agreement provided for in this Section 16 orwhich otherwise becomes bound by all the terms and provisions of this Agreementby operation of law.

## (b)           BindingAgreement.  This Agreement and allrights of the Executive hereunder shall inure to the benefit of and beenforceable by the Executive’s personal or legal representatives, executors,administrators, successors, heirs, distributees, devisees and legatees.  If the Executive should die while any amountswould still be payable to him hereunder if he had continued to live, all suchamounts, unless otherwise provided herein, shall be paid in accordance with theterms of this Agreement to the Executive’s devisee, legatee, or other designeeor, if there be no such designee, to the Executive’s estate.

# 17.           Representations.  The Executive hereby represents and warrantsto the Company that: (a) the execution, delivery and performance of thisAgreement by the Executive and the execution of the Company’s business plan bythe Executive do not and will not conflict with, breach, violate or cause adefault under any agreement, contract or instrument to which the Executive is aparty or any judgment, order or decree to which the Executive is subject, (b)this Agreement constitutes the legal, valid and binding obligation of theExecutive, enforceable in accordance with its terms, (c) the Executive has notand will not take any action that will conflict with, violate or cause a breachof any noncompete, nonsolicitation or confidentiality agreement to which theExecutive is a party or by which the Executive is bound and (d) the Executiveis a resident of the Commonwealth of Virginia. The Executive hereby acknowledges and represents that he has carefullyreviewed this Agreement, that he has consulted with independent legal counselregarding his rights and obligations under this Agreement (or, after carefullyreviewing this Agreement, was given the opportunity to, but has freely decidednot to, consult with independent legal counsel), and that he fully understandsthe terms and conditions contained herein.

18.           Certain Payments.  Anything in this Agreement to the contrarynotwithstanding, in the event it shall be determined that any payment ordistribution by the Company to or for the benefit of the Executive (whetherpaid or payable or distributed or distributable pursuant to the terms of thisAgreement or otherwise, but determined without regard to any additionalpayments required under this Section 18) (each a “Payment”, andcollectively, “Payments”) would be subject to the excise tax imposed bySection 4999 of the Code or any interest or penalties are incurred by theExecutive with respect to such excise tax (such excise tax, together with anysuch interest and penalties, are hereinafter collectively referred to as the “ExciseTax”), then the Executive shall be entitled to receive an additionalpayment (an “Additional Payment”) in an amount such that after paymentby the Executive of all taxes (including any interest or penalties imposed withrespect to such taxes), including, without limitation, any income taxes (andany interest and penalties imposed with respect thereto) and Excise Tax imposedupon the Additional Payment, the Executive retains an amount of the AdditionalPayment equal to the Excise Tax imposed upon the Payments.

# 19.           Notice.  All notices and other communications providedfor herein shall be in writing and shall be deemed to have been duly given,delivered and received (a) if delivered personally or (b) if sent by registeredor certified mail (return receipt requested) postage prepaid,

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# or by courierguaranteeing next day delivery, in each case to the party to whom it isdirected at the following addresses (or at such other address for any party asshall be specified by notice given in accordance with the provisions hereof,provided that notices of a change of address shall be effective only uponreceipt thereof).  Notices deliveredpersonally shall be effective on the day so delivered, notices sent byregistered or certified mail shall be effective three (3) days after mailing,and notices sent by courier guaranteeing next day delivery shall be effectiveon the next day after deposit with the courier:

If to the Executive:            S.Bradford Antle                                           15270Riding Club Drive                                           Haymarket,VA  20169

If to theCompany:             SIInternational, Inc.                                           12012 Sunset Hills Road, Suite 800                                           Reston,Virginia 20190-5869

# 20.           Prior Agreement. The OriginalAgreement is hereby superseded and terminated effective as of the date hereofand shall be without further force or effect.

# 21.           Miscellaneous.  No provisions of this Agreement may bemodified, waived or discharged, unless such waiver, modification or dischargeis agreed to in writing signed by the Executive and a duly authorized officerof the Company.  No waiver by eitherparty hereto at any time of any breach by the other hereto of, or compliancewith, any condition or provision of this Agreement to be performed by suchother party shall be deemed a waiver of similar or dissimilar provisions orconditions at the same or at any prior or subsequent time.  No agreements or representations, oral orotherwise, express or implied, with respect to the subject matter hereof havebeen made by either party which are not set forth expressly in thisAgreement.  The use herein of themasculine, feminine or neuter forms shall also denote the other forms, as ineach case the context may require.  Thevalidity, interpretation, construction and performance of this Agreement shallbe governed by the laws of the Commonwealth of Virginia, without regard to itsconflict of laws provisions.  All amountspayable to the Executive as compensation hereunder shall be subject tocustomary withholding by the Company. The Company and the Executive shall reasonably cooperate with respectto, and may jointly amend or modify the Agreement in any mutually agreeablemanner to provide for, the application and effects of Section 409A of the Codeand any related regulatory or administrative guidance issued by the InternalRevenue Service.

# 22.           Validity.  The invalidity or unenforceability of any provisionor provisions of this Agreement shall not affect the validity or enforceabilityof any other provision of this Agreement, which shall remain in full force andeffect.

23.           Survival.  Notwithstanding any termination of theExecutive’s employment under this Agreement, Sections 6 through 24hereof shall survive and continue in full force until the performance of theobligations thereunder, if any, in accordance with their respective terms.

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24.           Counterparts.  This Agreement may be executed in several counterparts,each of which shall be deemed to be an original but all of which together willconstitute one and the same instrument.

**[*Signatures appear on following page*]**

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IN WITNESSWHEREOF, the parties have executed this Agreement on the date and year firstabove written.
|            | ** ** | **COMPANY**                               |
|------------|------------|-------------------------------------------|
| ** ** | ** ** | ** **                                |
|       |       | SI INTERNATIONAL, INC.,                   |
|       |       | a Delaware corporation                    |
|       |       |                                      |
|       |       |                                      |
|       |       | By:                                       | /s/ Ray J. Oleson |
|       |       | Name: Ray J. Oleson                       |
|       |       | Title: Chairman of the Board of Directors |
|       |       |                                      |
|       |       |                                      |
| ** ** | ** ** | **EXECUTIVE**                             |
| ** ** | ** ** | ** **                                |
| ** ** | ** ** | ** **                                |
|       |       | /s/ S. Bradford Antle                     |
|       |       | S. Bradford Antle                         |

 

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