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  <p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>
  
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  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">UNITED
  STATES</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">SECURITIES
  AND EXCHANGE COMMISSION</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Washington,
  D.C.&nbsp; 20549</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">FORM&nbsp;8-K</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">CURRENT
  REPORT</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="3" face="Times New Roman" style="font-size:12.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">Pursuant
  to Section&nbsp;13 or 15(d)&nbsp;of the Securities Exchange Act of 1934</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date of Report (Date of earliest event
  reported):&nbsp;<b>April&nbsp;29, 2008</b></font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">SI
  International Inc.</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Exact Name of Registrant as Specified in
  its Charter)</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <div align="center">
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Delaware</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">000-50080</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">52-2127278</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(State or Other
    Jurisdiction<br>
    of Incorporation)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Commission File<br>
    Number)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(IRS Employer<br>
    Identification Number)</font></p>
    </td>
   </tr>
   <tr>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="66%" colspan="3" valign="top" style="padding:0in .7pt 0in .7pt;width:66.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">12012
    Sunset Hills Road</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="66%" colspan="3" valign="top" style="padding:0in .7pt 0in .7pt;width:66.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">8<sup>th</sup>
    Floor</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="66%" colspan="3" valign="top" style="padding:0in .7pt 0in .7pt;width:66.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Reston,
    Virginia</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">20190</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="66%" colspan="3" valign="top" style="padding:0in .7pt 0in .7pt;width:66.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Address of Principal
    Executive Offices)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="32%" valign="top" style="padding:0in .7pt 0in .7pt;width:32.0%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Zip Code)</font></p>
    </td>
   </tr>
  </table>
  
  </div>
  
  <p style="margin:0in 0in .0001pt;"><font size="3" face="Times New Roman">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Registrant&#146;s Telephone Number, including
  Area Code:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<b>(703)
  234-7000</b></font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Former Name or Former Address, if
  Changed Since Last Report)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Check
  the appropriate box below if the Form&nbsp;8-K filing is intended to
  simultaneously satisfy the filing obligation of the registrant under any of the
  following provisions (see General Instruction A.2. below):</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" face="Times New Roman" style="font-size:10.0pt;">
  Written communications pursuant to Rule&nbsp;425 under the Securities Act (17
  CFR 230.425)</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" face="Times New Roman" style="font-size:10.0pt;">
  Soliciting material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR
  240.14a-12)</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" face="Times New Roman" style="font-size:10.0pt;">
  Pre-commencement communications pursuant to Rule&nbsp;14d-2(b)&nbsp;under the
  Exchange Act (17 CFR 240.14d-2(b))</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="2" face="Times New Roman" style="font-size:10.0pt;">
  Pre-commencement communications pursuant to Rule&nbsp;13e-4(c)&nbsp;under the
  Exchange Act (17 CFR 240.13e-4(c))</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <div style="border:none;border-bottom:double windowtext 6.0pt;padding:0in 0in 0in 0in;">
  
  <p style="border:none;margin:0in 0in .0001pt;padding:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  </div>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='',FILE='C:\JMS\pselva\08-12940-1\task2902851\12940-1-ba.htm',USER='105344',CD='Apr 29 23:41 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Item 2.02&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; <u>Results of Operations and
  Financial Condition</u>.</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">On April&nbsp;29, 2008, SI International,&nbsp;Inc.
  (the &#147;Company&#148;) issued a press release announcing financial results for its
  fiscal first quarter ended March&nbsp;29, 2008, as well as reissuing its
  earnings guidance for the second quarter and full year of fiscal 2008.&#160; Such press release is incorporated by
  reference from Exhibit&nbsp;99.1 to this Form&nbsp;8-K and is furnished to, but
  not filed with, the Commission.</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Item 9.01&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; <u>Financial Statements and
  Exhibits</u>.</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:1.0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(d)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Exhibits</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="14%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:14.92%;">
    <p style="margin:0in 0in .0001pt;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;Number</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.26%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="82%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:82.84%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="14%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:14.92%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.26%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="82%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:82.84%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="14%" valign="top" style="padding:0in .7pt 0in .7pt;width:14.92%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">99.1</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.26%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="82%" valign="top" style="padding:0in .7pt 0in .7pt;width:82.84%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated
    April&nbsp;29, 2008</font></p>
    </td>
   </tr>
  </table>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The
  above-referenced statements may contain forward-looking statements that are
  made pursuant to the safe-harbor provisions of the Private Securities
  Litigation Reform Act of 1995. Expressions of future goals, financial
  information or reporting, and similar expressions reflecting something other
  than historical fact are intended to identify forward-looking statements, but
  are not the exclusive means of identifying such statements. These
  forward-looking statements may involve a number of risks and uncertainties,
  which are described in the Company&#146;s filings with the Securities and Exchange
  Commission. These risks and uncertainties include: changes in federal
  government (or other applicable) procurement laws, regulations, policies and
  budgets; risks relating to contract performance; changes in the risks
  associated with the competitive process or environment (including as a result
  of bid protests); and the important factors discussed in the Risk Factors
  section of the annual report on Form&nbsp;10-K filed by the Company with the
  Securities and Exchange Commission and available directly from the Commission
  at www.sec.gov. The actual results may differ materially from any
  forward-looking statements due to such risks and uncertainties. The Company
  undertakes no obligations to revise or update any forward-looking statements in
  order to reflect events or circumstances that may arise after the date of this
  release.</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>
  
  <div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='2',FILE='C:\JMS\pselva\08-12940-1\task2902851\12940-1-ba.htm',USER='105344',CD='Apr 29 23:41 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">SIGNATURES</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Pursuant to the requirements of the
  Securities Exchange Act of 1934, the registrant has duly caused this report to
  be signed on its behalf by the undersigned hereunto duly authorized.</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="53%" colspan="2" valign="top" style="padding:0in .7pt 0in .7pt;width:53.9%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">SI
    International,&nbsp;Inc.</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="48%" valign="top" style="padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="48%" valign="top" style="padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:</font></p>
    </td>
    <td width="48%" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/ Thomas E. Dunn</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="48%" valign="top" style="padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Thomas E. Dunn</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="48%" valign="top" style="padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Executive Vice President,</font></p>
    </td>
   </tr>
   <tr>
    <td width="46%" valign="top" style="padding:0in .7pt 0in .7pt;width:46.1%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.82%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="48%" valign="top" style="padding:0in .7pt 0in .7pt;width:48.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chief Financial Officer
    and Treasurer</font></p>
    </td>
   </tr>
  </table>
  
  <p style="margin:0in 0in .0001pt 2.5in;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt 2.5in;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Dated: April&nbsp;29, 2008</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>
  
  <div style="margin:0in 0in .0001pt;text-indent:0in;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='3',FILE='C:\JMS\pselva\08-12940-1\task2902851\12940-1-ba.htm',USER='105344',CD='Apr 29 23:41 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">INDEX TO EXHIBITS</font></p>
  
  <p style="margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="14%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:14.26%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;Number</font></b></p>
    </td>
    <td width="3%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:3.08%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="82%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:82.66%;">
    <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="14%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:14.26%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="3%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:3.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="82%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:82.66%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="14%" valign="top" style="padding:0in .7pt 0in .7pt;width:14.26%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">99.1</font></p>
    </td>
    <td width="3%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:3.08%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="82%" valign="top" style="padding:0in .7pt 0in .7pt;width:82.66%;">
    <p style="margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated
    April&nbsp;29, 2008</font></p>
    </td>
   </tr>
  </table>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4</font></p>
  
  <div style="margin:0in 0in .0001pt;text-indent:0in;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='4',FILE='C:\JMS\pselva\08-12940-1\task2902851\12940-1-ba.htm',USER='105344',CD='Apr 29 23:41 2008' -->
  
  
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metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "a08-12940_18k.htm", "description": "8-K", "secsgml_size_bytes": 30630}]
metadata_filer: {"company-data": {"conformed-name": "SI INTERNATIONAL INC", "cik": "0001143363", "assigned-sic": "7373", "irs-number": "522127278", "state-of-incorporation": "DE", "fiscal-year-end": "1230"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-50080", "film-number": "08785864"}, "business-address": {"street1": "12012 SUNSET HILLS ROAD", "street2": "SUITE 800", "city": "RESTON", "state": "VA", "zip": "20190-5869", "phone": "7032347000"}, "mail-address": {"street1": "12012 SUNSET HILLS ROAD", "street2": "SUITE 800", "city": "RESTON", "state": "VA", "zip": "20190"}}
text: UNITED
  STATES
  SECURITIES
  AND EXCHANGE COMMISSION
  Washington,
  D.C.  20549
  FORM 8-K
  CURRENT
  REPORT
  Pursuant
  to Section 13 or 15(d) of the Securities Exchange Act of 1934
  Date of Report (Date of earliest event
  reported):
  April 29, 2008
  SI
  International Inc.
  (Exact Name of Registrant as Specified in
  its Charter)
  Delaware
  000-50080
  52-2127278
  (State or Other
    Jurisdiction
  of Incorporation)
  (Commission File
  Number)
  (IRS Employer
  Identification Number)
  12012
    Sunset Hills Road
  8
  th
  Floor
  Reston,
    Virginia
  20190
  (Address of Principal
    Executive Offices)
  (Zip Code)
  Registrant's Telephone Number, including
  Area Code:
  (703)
  234-7000
  (Former Name or Former Address, if
  Changed Since Last Report)
  Check
  the appropriate box below if the Form 8-K filing is intended to
  simultaneously satisfy the filing obligation of the registrant under any of the
  following provisions (see General Instruction A.2. below):
  o
  Written communications pursuant to Rule 425 under the Securities Act (17
  CFR 230.425)
  o
  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
  240.14a-12)
  o
  Pre-commencement communications pursuant to Rule 14d-2(b) under the
  Exchange Act (17 CFR 240.14d-2(b))
  o
  Pre-commencement communications pursuant to Rule 13e-4(c) under the
  Exchange Act (17 CFR 240.13e-4(c))
  Item 2.02
  Results of Operations and
  Financial Condition
  .
  On April 29, 2008, SI International, Inc.
  (the "Company") issued a press release announcing financial results for its
  fiscal first quarter ended March 29, 2008, as well as reissuing its
  earnings guidance for the second quarter and full year of fiscal 2008.  Such press release is incorporated by
  reference from Exhibit 99.1 to this Form 8-K and is furnished to, but
  not filed with, the Commission.
  Item 9.01
  Financial Statements and
  Exhibits
  .
  (d)           Exhibits
  Exhibit Number
  Exhibit
  99.1
  Press Release dated
    April 29, 2008
  The
  above-referenced statements may contain forward-looking statements that are
  made pursuant to the safe-harbor provisions of the Private Securities
  Litigation Reform Act of 1995. Expressions of future goals, financial
  information or reporting, and similar expressions reflecting something other
  than historical fact are intended to identify forward-looking statements, but
  are not the exclusive means of identifying such statements. These
  forward-looking statements may involve a number of risks and uncertainties,
  which are described in the Company's filings with the Securities and Exchange
  Commission. These risks and uncertainties include: changes in federal
  government (or other applicable) procurement laws, regulations, policies and
  budgets; risks relating to contract performance; changes in the risks
  associated with the competitive process or environment (including as a result
  of bid protests); and the important factors discussed in the Risk Factors
  section of the annual report on Form 10-K filed by the Company with the
  Securities and Exchange Commission and available directly from the Commission
  at www.sec.gov. The actual results may differ materially from any
  forward-looking statements due to such risks and uncertainties. The Company
  undertakes no obligations to revise or update any forward-looking statements in
  order to reflect events or circumstances that may arise after the date of this
  release.
  2
  SIGNATURES
  Pursuant to the requirements of the
  Securities Exchange Act of 1934, the registrant has duly caused this report to
  be signed on its behalf by the undersigned hereunto duly authorized.
  SI
    International, Inc.
  By:
  /s/ Thomas E. Dunn
  Thomas E. Dunn
  Executive Vice President,
  Chief Financial Officer
    and Treasurer
  Dated: April 29, 2008
  3
  INDEX TO EXHIBITS
  Exhibit Number
  Exhibit
  99.1
  Press Release dated
    April 29, 2008
  4