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  <p align="center" style="border:none;margin:0in 0in .0001pt;padding:0in;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>
  
  </div>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</font></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;"><br>
  Washington, D.C.&nbsp;&nbsp;20549</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">Current Report Pursuant to
  Section&nbsp;13 or 15(d)<br>
  of the Securities Exchange Act of 1934</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">May&nbsp;9, 2008</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date of Report (Date of
  earliest event reported)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">Arch Capital Group Ltd.</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><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;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Bermuda</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">0-26456</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">N/A</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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(State or other<br>
    jurisdiction of<br>
    incorporation or<br>
    organization)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Commission File Number)</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(I.R.S. Employer<br>
    Identification No.)</font></p>
    </td>
   </tr>
  </table>
  
  </div>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Wessex House, 45 Reid
  Street, Hamilton HM 12, Bermuda</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Address of principal
  executive offices) (Zip Code)</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Registrant&#146;s telephone
  number, including area code:<br>
  <b>(441) 278-9250</b></font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">N/A</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><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;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" 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;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" 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;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" 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;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Wingdings" style="font-size:10.0pt;">o</font><font size="1" style="font-size:3.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font><font size="2" 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;punctuation-wrap:simple;text-autospace:none;"><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;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  </div>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <div style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='',FILE='C:\JMS\jtaylora\08-14583-1\task2942947\14583-1-ba.htm',USER='jtaylora',CD='May 15 10:37 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div style="font-family:Times New Roman;">
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><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="9%" valign="top" style="padding:0in .7pt 0in .7pt;width:9.02%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">ITEM 5.02</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.2%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="88%" valign="top" style="padding:0in .7pt 0in .7pt;width:88.78%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><b><u><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Departure of Directors or Certain Officers;
    Election of Directors; Appointment of Certain Officers; Compensatory
    Arrangements of Certain Officers</font></u></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">.</font></b></p>
    </td>
   </tr>
  </table>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Mark Lyons has been promoted to the position of Chairman
  and Chief Executive Officer of Arch Worldwide Insurance Group, effective July&nbsp;2,
  2008. Mr.&nbsp;Lyons, who joined Arch in 2002 and currently serves as President
  and Chief Operating Officer of Arch&#146;s U.S.-based insurance group, will succeed
  Ralph Jones, who will be retiring at the end of his five-year employment term
  on July&nbsp;1, 2008.</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Following is certain biographical information on Mr.&nbsp;Lyons:</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt .5in;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Mr.&nbsp;Lyons,
  age 51, has served as president and chief operating officer of Arch Insurance
  Group since June&nbsp;2006. Prior to June&nbsp;2006, he served as executive
  vice president of group operations and chief actuary of Arch Insurance Group
  from August&nbsp;2003. From August&nbsp;2002 to 2003, he was senior vice
  president of group operations and chief actuary of Arch Insurance Group. From
  2001 until August&nbsp;2002, Mr.&nbsp;Lyons worked as an independent
  consultant. From 1992 to 2001, Mr.&nbsp;Lyons was executive vice president of
  product services at Zurich U.S. From 1987 until 1992, he was a vice president
  and actuary at Berkshire Hathaway Insurance Group. Mr.&nbsp;Lyons holds a B.S.
  degree from Elizabethtown College. He is also an associate of the Casualty
  Actuarial Society and a member of the American Academy of Actuaries.</font></p>
  
  <p style="margin:0in 0in .0001pt .5in;punctuation-wrap:simple;text-autospace:none;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; In connection with Mr.&nbsp;Jones&#146;
  retirement, Arch Capital Group Ltd. (&#147;ACGL&#148;), Arch Insurance Group Inc. and Mr.&nbsp;Jones
  entered into an agreement pursuant to which outstanding share-based awards
  previously granted to Mr.&nbsp;Jones would be permitted to vest in accordance
  with the normal vesting schedule included in the applicable agreements and
  vested stock options and share appreciation rights may be exercised for a
  period ending three years after the last date of Mr.&nbsp;Jones&#146; employment,
  provided Mr.&nbsp;Jones does not compete with ACGL and its subsidiaries as set
  forth in the agreement.</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">&nbsp;</font></b></p>
  
  <p style="margin:0in 0in .0001pt .8in;punctuation-wrap:simple;text-autospace:none;text-indent:-.8in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">ITEM 7.01</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><u><font size="2" style="font-size:10.0pt;font-weight:bold;">Regulation FD Disclosure</font></u></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">.</font></b></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:hanging;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">On May&nbsp;15,
  2008, ACGL issued a press release announcing the management changes described
  in Item 5.02.&#160; A copy of this press
  release is attached to this Current Report on Form&nbsp;8-K as Exhibit&nbsp;99.1
  and is incorporated herein by reference.</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:hanging;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">The information in Section&nbsp;7.01 of this Current
  Report on Form&nbsp;8-K, including the information set forth in Exhibit&nbsp;99.1,
  shall not be deemed &#147;filed&#148; for purposes of Section&nbsp;18 of the Securities Exchange
  Act of 1934, as amended (the &#147;Exchange Act&#148;), or incorporated by reference in
  any filing under the Securities Act of 1933, as amended, or the Exchange Act,
  except as shall be expressly set forth by specific reference in such a filing.</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt .8in;punctuation-wrap:simple;text-autospace:none;text-indent:-.8in;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">ITEM 9.01</font></b><b><font size="1" style="font-size:3.0pt;font-weight:bold;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; </font></b><b><u><font size="2" style="font-size:10.0pt;font-weight:bold;">Financial Statements and
  Exhibits</font></u></b><b><font size="2" style="font-size:10.0pt;font-weight:bold;">.</font></b></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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="12%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">EXHIBIT NO.</font></b></p>
    </td>
    <td width="3%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:3.88%;">
    <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="84%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">DESCRIPTION</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="12%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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:3.88%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="84%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="12%" valign="top" style="padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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:3.88%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="84%" valign="top" style="padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated May&nbsp;15, 2008 announcing </font><font size="2" style="font-size:10.0pt;">the management changes described in
    Item 5.02.</font></p>
    </td>
   </tr>
  </table>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>
  
  <div style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='2',FILE='C:\JMS\jtaylora\08-14583-1\task2942947\14583-1-ba.htm',USER='jtaylora',CD='May 15 10:37 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">SIGNATURES</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;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, as amended, the registrant has duly caused this report to
  be signed on its behalf by the undersigned.</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="99%" style="border-collapse:collapse;width:99.24%;">
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="357" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:267.95pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">ARCH CAPITAL
    GROUP LTD.</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="357" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:267.95pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="357" colspan="3" valign="top" style="padding:0in 0in 0in 0in;width:267.95pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Date:&nbsp; May&nbsp;15, 2008</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="26" valign="top" style="padding:0in 0in 0in 0in;width:19.15pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By:</font></p>
    </td>
    <td width="332" colspan="2" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 0in 0in;width:248.8pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/ John D.
    Vollaro</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="26" valign="top" style="padding:0in 0in 0in 0in;width:19.15pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="332" colspan="2" valign="top" style="border:none;padding:0in 0in 0in 0in;width:248.8pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name:&nbsp; John D. Vollaro</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="26" valign="top" style="padding:0in 0in 0in 0in;width:19.15pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="35" valign="top" style="padding:0in 0in 0in 0in;width:26.55pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Title:</font></p>
    </td>
    <td width="296" valign="top" style="padding:0in 0in 0in 0in;width:222.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Executive Vice
    President,</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="26" valign="top" style="padding:0in 0in 0in 0in;width:19.15pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="35" valign="top" style="padding:0in 0in 0in 0in;width:26.55pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="296" valign="top" style="padding:0in 0in 0in 0in;width:222.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Chief Financial
    Officer and</font></p>
    </td>
   </tr>
   <tr>
    <td width="339" valign="top" style="padding:0in 0in 0in 0in;width:254.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="18" valign="top" style="padding:0in 0in 0in 0in;width:13.7pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="26" valign="top" style="padding:0in 0in 0in 0in;width:19.15pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="35" valign="top" style="padding:0in 0in 0in 0in;width:26.55pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="296" valign="top" style="padding:0in 0in 0in 0in;width:222.25pt;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Treasurer</font></p>
    </td>
   </tr>
  </table>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>
  
  <div style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='3',FILE='C:\JMS\jtaylora\08-14583-1\task2942947\14583-1-ba.htm',USER='jtaylora',CD='May 15 10:37 2008' -->
  
  
  <br clear="all" style="page-break-before:always;">
  
  
  <div style="font-family:Times New Roman;">
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">EXHIBIT INDEX</font></b></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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="12%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">EXHIBIT NO.</font></b></p>
    </td>
    <td width="3%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:3.88%;">
    <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="84%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">DESCRIPTION</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="12%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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:3.88%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="84%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="12%" valign="top" style="padding:0in .7pt 0in .7pt;width:12.0%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><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:3.88%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="84%" valign="top" style="padding:0in .7pt 0in .7pt;width:84.12%;">
    <p style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated May&nbsp;15, 2008 announcing </font><font size="2" style="font-size:10.0pt;">the management changes described in
    Item 5.02</font><font size="2" style="font-size:10.0pt;">.</font></p>
    </td>
   </tr>
  </table>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4</font></p>
  
  <div style="margin:0in 0in .0001pt;punctuation-wrap:simple;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='4',FILE='C:\JMS\jtaylora\08-14583-1\task2942947\14583-1-ba.htm',USER='jtaylora',CD='May 15 10:37 2008' -->
  
  
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metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "a08-14583_18k.htm", "description": "8-K", "secsgml_size_bytes": 38083}]
metadata_filer: {"company-data": {"conformed-name": "ARCH CAPITAL GROUP LTD.", "cik": "0000947484", "assigned-sic": "6331", "irs-number": "000000000", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-16209", "film-number": "08835121"}, "business-address": {"street1": "WESSEX HOUSE", "street2": "45 REID STREET", "city": "HAMILTON", "state": "D0", "zip": "HM 12", "phone": "441-278-9250"}, "mail-address": {"street1": "WESSEX HOUSE", "street2": "45 REID STREET", "city": "HAMILTON", "state": "D0", "zip": "HM 12"}, "former-company": [{"former-conformed-name": "ARCH CAPITAL GROUP LTD", "date-changed": "20000508"}, {"former-conformed-name": "RISK CAPITAL HOLDINGS INC", "date-changed": "19950816"}, {"former-conformed-name": "RISK CAPITAL RE INC", "date-changed": "19950703"}]}
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
  May 9, 2008
  Date of Report (Date of
  earliest event reported)
  Arch Capital Group Ltd.
  (Exact name of registrant as
  specified in its charter)
  Bermuda
  0-26456
  N/A
  (State or other
  jurisdiction of
  incorporation or
  organization)
  (Commission File Number)
  (I.R.S. Employer
  Identification No.)
  Wessex House, 45 Reid
  Street, Hamilton HM 12, Bermuda
  (Address of principal
  executive offices) (Zip Code)
  Registrant's telephone
  number, including area code:
  (441) 278-9250
  N/A
  (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 5.02
  Departure of Directors or Certain Officers;
    Election of Directors; Appointment of Certain Officers; Compensatory
    Arrangements of Certain Officers
  .
  Mark Lyons has been promoted to the position of Chairman
  and Chief Executive Officer of Arch Worldwide Insurance Group, effective July 2,
  2008. Mr. Lyons, who joined Arch in 2002 and currently serves as President
  and Chief Operating Officer of Arch's U.S.-based insurance group, will succeed
  Ralph Jones, who will be retiring at the end of his five-year employment term
  on July 1, 2008.
  Following is certain biographical information on Mr. Lyons:
  Mr. Lyons,
  age 51, has served as president and chief operating officer of Arch Insurance
  Group since June 2006. Prior to June 2006, he served as executive
  vice president of group operations and chief actuary of Arch Insurance Group
  from August 2003. From August 2002 to 2003, he was senior vice
  president of group operations and chief actuary of Arch Insurance Group. From
  2001 until August 2002, Mr. Lyons worked as an independent
  consultant. From 1992 to 2001, Mr. Lyons was executive vice president of
  product services at Zurich U.S. From 1987 until 1992, he was a vice president
  and actuary at Berkshire Hathaway Insurance Group. Mr. Lyons holds a B.S.
  degree from Elizabethtown College. He is also an associate of the Casualty
  Actuarial Society and a member of the American Academy of Actuaries.
  In connection with Mr. Jones'
  retirement, Arch Capital Group Ltd. ("ACGL"), Arch Insurance Group Inc. and Mr. Jones
  entered into an agreement pursuant to which outstanding share-based awards
  previously granted to Mr. Jones would be permitted to vest in accordance
  with the normal vesting schedule included in the applicable agreements and
  vested stock options and share appreciation rights may be exercised for a
  period ending three years after the last date of Mr. Jones' employment,
  provided Mr. Jones does not compete with ACGL and its subsidiaries as set
  forth in the agreement.
  ITEM 7.01
  Regulation FD Disclosure
  .
  On May 15,
  2008, ACGL issued a press release announcing the management changes described
  in Item 5.02.  A copy of this press
  release is attached to this Current Report on Form 8-K as Exhibit 99.1
  and is incorporated herein by reference.
  The information in Section 7.01 of this Current
  Report on Form 8-K, including the information set forth in Exhibit 99.1,
  shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange
  Act of 1934, as amended (the "Exchange Act"), or incorporated by reference in
  any filing under the Securities Act of 1933, as amended, or the Exchange Act,
  except as shall be expressly set forth by specific reference in such a filing.
  ITEM 9.01
  Financial Statements and
  Exhibits
  .
  EXHIBIT NO.
  DESCRIPTION
  99.1
  Press Release dated May 15, 2008 announcing
  the management changes described in
    Item 5.02.
  2
  SIGNATURES
  Pursuant to the requirements of the Securities
  Exchange Act of 1934, as amended, the registrant has duly caused this report to
  be signed on its behalf by the undersigned.
  ARCH CAPITAL
    GROUP LTD.
  Date:  May 15, 2008
  By:
  /s/ John D.
    Vollaro
  Name:  John D. Vollaro
  Title:
  Executive Vice
    President,
  Chief Financial
    Officer and
  Treasurer
  3
  EXHIBIT INDEX
  EXHIBIT NO.
  DESCRIPTION
  99.1
  Press Release dated May 15, 2008 announcing
  the management changes described in
    Item 5.02
  .
  4