ACCOUNT CONTROL AGREEMENT

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                             [CLIFFORD CHANCE LOGO]



                                                                   EXHIBIT 10.36

       
                                                                  EXECUTION COPY


                                BARCLAYS BANK PLC
                                AS SECURED PARTY

                       ALLIED WORLD ASSURANCE COMPANY, LTD
                                   AS PLEDGOR

                                MELLON BANK, N.A.
                                     AS BANK

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                            ACCOUNT CONTROL AGREEMENT

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                                    CONTENTS

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CLAUSE                                                            PAGE
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1.  The Account...............................................     3
2.  Control By Secured Party..................................     3
3.  Pledgor's Rights In Account...............................     3
4.  Priority Of Secured Party's Security Interest.............     6
5.  Statements, Confirmations And Notices Of Adverse Claims...     6
6.  Bank's Responsibility.....................................     6
7.  Indemnity.................................................     7
8.  Termination; Survival.....................................     7
9.  Governing Law.............................................     8
10. Entire Agreement..........................................     8
11. Amendments................................................     8
12. Severability..............................................     8
13. Successors And Assigns....................................     8
14. Notices...................................................     8
15. Counterparts..............................................     8
16. Waiver Of Jury Trial......................................     8
17. Representations...........................................     9    

EXHIBIT A.....................................................   

EXHIBIT B.....................................................

Schedule 1....................................................         
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THIS AGREEMENT dated as of 31 December 2003

BETWEEN

(1)   BARCLAYS BANK PLC, as Secured Party;

(2)   ALLIED WORLD ASSURANCE COMPANY, LTD, as Pledgor; and

(3)   MELLON BANK, N.A., as Bank

BACKGROUND

(A)   Pledgor has granted Secured Party a security interest in the financial
      assets in the securities account identified in Schedule 1 (the "ACCOUNT"),
      maintained by Bank for Pledgor, (including any security entitlement) and
      in the Account.

(B)   The parties are entering into this agreement to provide for the control of
      the Account as a means to perfect the security interest of Secured Party.
      Bank has no responsibility to Secured Party in respect to the validity or
      perfection of such security interest otherwise than to act in accordance
      with the terms and conditions of this Agreement.

1.    THE ACCOUNT

      Bank represents and warrants to Secured Party that Bank maintains the
      Account. Bank represents and warrants that except for the claim and
      interest of Pledgor and Secured Party, or as provided in Clause 4 of this
      Agreement, Bank does not know of any claim to or interest in the Account
      or any financial assets credited thereto. Bank, Pledgor and Secured Party
      agree that the Account is a securities account ("SECURITIES ACCOUNT") as
      that term is defined in Section 8-501(a) of the Uniform Commercial Code as
      in effect from time to time in the State of New York (the "NYUCC"). Bank,
      Pledgor and Secured Party agree that each item of property (whether
      investment property, financial asset, security, instrument or cash)
      credited to the Account shall be treated as a financial asset ("FINANCIAL
      ASSET") within the meaning of Section 8-102(a)(9) of the NYUCC.

2.    CONTROL BY SECURED PARTY

      Bank will comply with all notifications it receives directing it to
      transfer or redeem any financial assets credited to the Account (each an
      entitlement order ("ENTITLEMENT ORDER") as defined in Section 8-102(a)(8)
      of the NYUCC) originated by Secured Party and shall otherwise treat
      Secured Party as entitled to exercise the rights in respect of any
      financial asset credited to the Account without further consent by
      Pledgor.

3.    PLEDGOR'S RIGHTS IN ACCOUNT

      Subject to this Clause 3, until Bank receives an entitlement order from
      the Secured Party, Bank may accept and comply with any entitlement order
      from Pledgor with regard to the Account or any financial asset as follows:

                                      -3-
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      3.1.1 Until Bank receives an entitlement order from Secured Party, Bank
            shall distribute to Pledgor all cash distributions received in
            regard to financial assets in the Account. Cash distributions do not
            include any principal received upon redemption or maturity of a
            financial asset, and any such cash will be held for the benefit of
            Secured Party.

      3.1.2 Pledgor shall not direct Bank to release any of the financial assets
            in the Account or to close the Account and Bank agrees that it will
            not release any of the financial assets in the Account or close the
            Account without Secured Party's consent. For this purpose the term
            "release" shall be broadly construed to include release for any
            purpose, including (without limitation) release for settlement of a
            sale, release for the purposes of substituting new financial assets,
            release "free" without consideration and any other manner of leaving
            the Account. Secured Party will consent to the release of the
            financial assets provided that with respect to such financial
            assets, the following procedure is adhered to:

            (a)   Pledgor will determine (the "DETERMINATION") that the
                  financial assets remaining in the Account will be equal to or
                  exceed the required Adjusted Collateral Value (as more
                  specifically defined and described in a Credit Agreement dated
                  as of 31 December 2003 between Pledgor and Secured Party) (the
                  "REQUIRED ACCOUNT VALUE") and to determine this shall
                  diligently and in good faith:

                  (i)   determine that the financial asset is eligible as
                        collateral as specified in Exhibit A hereto; and

                  (ii)  use the mark-to-market value provided by pricing
                        services used by Bank in connection with the valuation
                        of financial assets under similar acco