EXHIBIT 10.24

                        ASPEN INSURANCE HOLDINGS LIMITED

                       NONQUALIFIED SHARE OPTION AGREEMENT

                  THIS AGREEMENT (the "Agreement"), is made effective as of the
     day of        , 2005 (hereinafter called the "Date of Grant"), between
Aspen Insurance Holdings Limited, a Bermuda corporation (hereinafter called the
"Company"), and               (hereinafter called the "Participant"):

                                R E C I T A L S:
                                - - - - - - - -
                  WHEREAS, the Company has adopted the Aspen Insurance Holdings
2003 Share Incentive Plan (the "Plan"), which Plan is incorporated herein by
reference and made a part of this Agreement. Capitalized terms not otherwise
defined herein shall have the same meanings as in the Plan; and

                  WHEREAS, the Committee has determined that it would be in the
best interests of the Company and its shareholders to grant the
performance-based option provided for herein to the Participant pursuant to the
Plan and the terms set forth herein.

                  NOW THEREFORE, in consideration of the mutual covenants
hereinafter set forth, the parties agree as follows:

1.    Grant of the Option. The Company hereby grants to the Participant the
      right and option to purchase, on the terms and conditions hereinafter set
      forth, all or any part of an aggregate of Shares (the "Option"), subject
      to adjustment as set forth in the Plan. The purchase price of the Shares
      subject to the Option shall be $25.88 per Share (the "Option Price"). The
      Option is intended to be a non-qualified share option, and is not intended
      to be treated as an option that complies with Section 422 of the Code.

2.    Vesting. The Option shall become vested only to the extent that the Return
      on Equity (calculated as described in Section 2(a) below, the "ROE")
      targets described below are achieved.

      (a)   For purposes of this agreement, "ROE" shall be equal to net income
            determined under United States Generally Accepted Accounting
            Principles ("US GAAP") after deduction of the cost of all Awards
            granted under the Plan as a percentage of weighted average
            shareholders' equity, which shall be determined by the Board based
            on the Company's audited financials under US GAAP.

      (b)   For purposes of this Agreement, "2005 ROE Percentage" shall be equal
            to the Company's actual ROE for the fiscal year ended December 31,
            2005 (the "2005 Fiscal Year"), expressed as a percentage of the ROE
            target for the 2005 Fiscal Year. The ROE target with respect to the
            2005 Fiscal Year is set forth on Exhibit A, a copy of which is
            attached hereto and incorporated herein by reference.

      (c)   The number of Shares underlying the Option that are eligible for
            vesting (the "Eligible Shares") shall depend on the Company's 2005
            ROE Percentage. If the Company's 2005 ROE Percentage is 100% or
            more, all of the Shares underlying the Option shall become Eligible
            Shares. If the Company's 2005 ROE Percentage is less than 100% but
            not less than 66.67%, then a reduced number of Shares underlying the
            Option shall be Eligible Shares as follows:

                2005 ROE Percentage            Percentage of Eligible Shares
                -------------------            -----------------------------
                     < 66.67%                               0%

                       66.67%                              10%

                        75%                               32.50%

                       83.33%                              55%

                       91.67%                             77.50%

                       > = 100%                            100%

                    Interim percentages to be interpolated linearly.

            If the Company's 2005 ROE Percentage is less than 66.67% or if in
            any case the Company's actual ROE for the 2005 Fiscal Year is less
            than 10%, none of the Shares underlying the Option shall become
            Eligible Shares and the Option shall immediately be forfeited
            without consideration.

      (d)   Eligible Shares underlying the Option shall become vested in thirds,
            with (i) one-third (1/3) becoming vested upon the later of (x) the
            date the Company's outside auditors complete the audit of the
            Company's financial statements containing the information necessary
            to compute the Company's ROE for the 2005 Fiscal Year or (y) the
            date such ROE is approved by the Board of Directors or an authorized
            committee thereof (the "Initial Vesting Date"), (ii) one-third (1/3)
            becoming vested on the first anniversary of the Initial Vesting
            Date, and (iii) one-third (1/3) becoming vested on the second
            anniversary of the Initial Vesting Date.

      (e)   In connection with any event described in Section 10(a) of the Plan
            or in the event of a change in applicable accounting rules, the
            Committee shall make such adjustments in the terms of the Option,
            including but not limited to the ROE targets, if any, as it shall
            determine shall be necessary to equitably reflect such event in
            order to prevent dilution or enlargement of the potential benefits
            of the Option. The Committee's determination as to any such
            adjustment shall be final.

      (f)   If the Participant's Employment with the Company is terminated for
            any reason, the Option shall, to the extent not then vested, be
            canceled by the Company without consideration and the portion of the
            Option that has vested shall be exercisable only as set forth in
            Section 3; provided, however, that in the event the

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            Participant is terminated for Cause (as defined below), the portion
            of the Option that has vested shall immediately be canceled without
            consideration to the extent not previously exercised.

3.    Exercise of Option.

      (a)   The portion of the Option that has vested shall become exercisable:

            (i)   Except as provided in Section 3(a)(ii), subject to the
                  Participant's continued Employment with the Company (which
                  Employment shall not include the performance of services under
                  a notice of termination or resignation), on the second
                  anniversary of the Initial Vesting Date; or

            (ii)  In the event of the Participant's termination of Employment
                  (A) by the Company without Cause, (B) due to death or
                  Disability (as defined below) or (C) by the Participant with
                  Good Reason (as defined below), on the date of termination.

      (b)   At any time, the portion of the Option that has become vested and
            exercisable pursuant to Section 2 and Section 3(a) is hereinafter
            referred to as the "Exercisable Portion."

      (c)   Period of Exercise. Subject to the provisions of the Plan and this
            Agreement, the Participant may exercise all or any part of the
            Exercisable Portion of the Option at any time prior to the earliest
            to occur of:

            (i)   the tenth anniversary of the Date of Grant;

            (ii)  the first anniversary of the Participant's termination of
                  Employment due to death or Disability;

            (iii) the first anniversary of the Participant's termination of
                  Employment by the Company without Cause (for any reason other
                  than due to death or Disability) or by the Participant with
                  Good Reason;

            (iv)  three months following the date of the Participant's
                  termination of Employment by the Participant for any reason
                  (other than due to death or Disability or Good Reason); and

            (v)   the date of the Participant's termination of Employment by the
                  Company for Cause.

            If the Participant has entered into an employment or service
            agreement with the Company or any of its Affiliates, the definition
            of "Cause" set forth in such agreement shall apply for purposes of
            this Agreement. Otherwise, "Cause" shall mean (i) Participant's
            engagement in misconduct which is materially injurious to the
            Company or any of its Affiliates, (ii) Participant's continued
            failure to substantially perform his or her duties to the Company or
            any of its Affiliates, (iii)

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            Participant's repeated dishonesty in the performance of his or her
            duties to the Company or any of its Affiliates, (iv) Participant's
            commission of an act or acts constituting any (x) fraud against, or
            misappropriation or embezzlement from the Company or any of its
            Affiliates, (y) crime involving moral turpitude, or (z) criminal
            offense that could result in a jail sentence of at least 30 days,
            (v) Participant's continued failure to comply with the material
            applicable rules and regulations of any regulatory authority with
            regulatory jurisdiction over the Company or any of its Affiliates,
            or (vi) Participant's material breach of any confidentiality or
            non-competition covenant entered into between the Participant and
            the Company, provided that, with respect to such a breach of
            covenant that could be cured, the Participant did not promptly cure
            such breach. The determination of the existence of Cause shall be
            made by the Committee in good faith. Notwithstanding anything in
            this Agreement to the contrary, if the Committee determines in good
            faith that grounds for termination of the Participant's Employment
            for Cause exist or existed at the time of termination of the
            Participant's Employment for any reason, then, for all purposes, the
            Option shall be treated as if such termination of the Participant's
            Employment were or had been for Cause.

            For purposes of this Agreement, "Disability" shall mean the
            inability of a Participant to perform in all material respects his
            or her duties and responsibilities to the Company, or any Affiliate
            of the Company, by reason of a physical or mental disability or
            infirmity which inability is reasonably expected to be permanent and
            has continued (i) for a period of six consecutive months or (ii)
            such shorter period as the Committee may determine in good faith.
            The Disability determination shall be in the sole discretion of the
            Committee and a Participant (or his or her representative) shall
            furnish the Committee with medical evidence documenting the
            Participant's disability or infirmity, which is reasonably
            satisfactory to the Committee.

            For purposes of this Agreement, "Good Reason" shall mean (i) a
            reduction in the Participant's annual base salary or annual bonus
            opportunity, or the failure to pay or provide the same when due,
            (ii) a material diminution in the Participant's duties, authority,
            responsibilities or title, or the assignment to the Participant of
            duties or responsibilities which are materially inconsistent with
            his position, (iii) a material adverse change in the Participant's
            reporting relationship, or (iv) the Company's requiring the
            Participant to be based at any office or location more than fifty
            (50) miles from the Participant's office at the time of the
            Effective Date; provided, however, that no such event(s) shall
            constitute "Good Reason" unless the Company shall have failed to
            cure such event(s) within 30 days after receipt by the Company from
            the Participant of written notice describing in detail such
            event(s).

      (d)   Method of Exercise.

            (i)   Subject to Section 3(b), the Exercisable Portion of the Option
                  may be exercised by delivering to the Company at its principal
                  office written

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                  notice of intent to so exercise; provided that the Option may
                  be exercised with respect to whole Shares only. Such notice
                  shall specify the number of Shares for which an Option is
                  being exercised and the method of payment of the Option Price.
                  The Option Price for the Shares as to which the Option is
                  exercised shall be paid to the Company, as designated by the
                  Committee, pursuant to one or more of the following methods:
                  (A) in cash or its equivalent (e.g., by check); (B) in Shares
                  having a Fair Market Value equal to the aggregate Option Price
                  for the Shares being purchased and satisfying such other
                  requirements as may be imposed by the Committee; (C) partly in
                  cash and partly in such Shares; or (D) by delivery of
                  irrevocable instructions to a broker to sell Shares obtained
                  upon the exercise of the Option and to deliver promptly to the
                  Company an amount out of the proceeds of such sale equal to
                  the aggregate Option Price for the Shares being purchased. No
                  Participant shall have any rights to dividends or other rights
                  of a shareholder with respect to Shares subject to the Option
                  until the Participant has given written notice of exercise of
                  the Option, paid in full for such Shares and, if applicable,
                  has satisfied any other conditions imposed by the Committee
                  pursuant to the Plan.

            (ii)  Notwithstanding any other provision of the Plan or this
                  Agreement to the contrary, the Option may not be exercised
                  prior to the completion of any registration or qualification
                  of the Option or the Shares under applicable state and federal
                  securities or other laws, or under any ruling or regulation of
                  any governmental body or national securities exchange that the
                  Committee shall in its sole discretion determine to be
                  necessary or advisable.

            (iii) Upon the Company's determination that the Option has been
                  validly exercised as to any of the Shares, the Company shall
                  issue certificates in the Participant's name for such Shares.
                  However, the Company shall not be liable to the Participant
                  for damages relating to any delays in issuing the certificates
                  to him, any loss of the certificates, or any mistakes or
                  errors in the issuance of the certificates or in the
                  certificates themselves.

            (iv)  In the event of the Participant's death, subject to Section 6,
                  the Exercisable Portion of the Option shall remain exercisable
                  by the Participant's executor or administrator, or the person
                  or persons to whom the Participant's rights under this
                  Agreement shall pass by will or by the laws of descent and
                  distribution as the case may be, to the extent set forth in
                  Section 3(b). Any heir or legatee of the Participant shall
                  take rights herein granted subject to the terms and conditions
                  hereof.

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4.    No Right to Continued Employment. The granting of the Option evidenced
      hereby and this Agreement shall impose no obligation on the Company or any
      Affiliate to continue the Employment of the Participant and shall not
      lessen or affect the Company's or its Affiliate's right to terminate the
      Employment of such Participant.

5.    Legend on Certificates. The certificates representing the Shares purchased
      by exercise of the Option shall be subject to such stop transfer orders
      and other restrictions as the Committee may deem advisable under the Plan
      or the rules, regulations, and other requirements of the Securities and
      Exchange Commission, any stock exchange upon which such Shares are listed,
      and any applicable laws, and the Committee may cause a legend or legends
      to be put on any such certificates to make appropriate reference to such
      restrictions.

6.    Transferability.

      (a)   The Option may not be assigned, alienated, pledged, attached, sold
            or otherwise transferred or encumbered by the Participant otherwise
            than by will or by the laws of descent and distribution, and any
            such purported assignment, alienation, pledge, attachment, sale,
            transfer or encumbrance shall be void and unenforceable against the
            Company or any Affiliate; provided that the designation of a
            beneficiary shall not constitute an assignment, alienation, pledge,
            attachment, sale, transfer or encumbrance; provided, further, that,
            upon written request by the Participant, the Committee may, subject
            to such rules as the Committee may adopt, permit the Option to be
            transferred by the Participant to (i) the Participant's spouse,
            children or grandchildren (including adopted and stepchildren and
            grandchildren) (collectively, the "Immediate Family"); (ii) a trust
            primarily for the benefit of the Participant and/or members of his
            or her Immediate Family (a "Family Trust"); or (iii) a partnership
            or limited liability company or other entity whose only partners or
            other equity owners are a Family Trust, the Participant and/or his
            or her Immediate Family members (each transferee described in
            clauses (i), (ii) and (iii) above is hereinafter referred to as a
            "Permitted Transferee"). The request by the Participant shall
            describe the terms and conditions of the proposed transfer and the
            Committee shall notify the Participant in writing if such a transfer
            will be permitted.

      (b)   Following a permitted transfer described in Section 6(a) above, all
            terms of the Option shall apply to the Permitted Transferee and any
            reference in the Plan and in the Agreement to a Participant shall be
            deemed to refer to the Permitted Transferee, except that (i)
            Permitted Transferees shall not be entitled to transfer the Option,
            other than by will or the laws of descent and distribution, (ii)
            Permitted Transferees shall not be entitled to exercise any
            transferred Option unless there shall be in effect a registration
            statement on an appropriate form covering the shares to be acquired
            pursuant to the exercise of such Option if the Committee determines
            that such a registration statement is necessary or appropriate,
            (iii) the Committee or the Company shall not be required to provide
            any notice to a Permitted Transferee, whether or not such notice is
            or would otherwise have been required to be given to the Participant
            under the Plan or

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            otherwise; provided that, if such notice is not provided to the
            Permitted Transferee, such notices are delivered by the Company to
            the Participant and (iv) the consequences of termination of the
            Participant's Employment under the terms of the Plan and the
            Agreement shall continue to be applied with respect to the
            Participant, following which the transferred Option shall be
            exercisable by the Permitted Transferee only to the extent, and for
            the periods, specified in the Plan and the Agreement. No permitted
            transfer of the Option to heirs or legatees of the Participant shall
            be effective to bind the Company unless the Committee shall have
            been furnished with written notice thereof and a copy of such
            evidence as the Committee may deem necessary to establish the
            validity of the transfer and the acceptance by the transferee or
            transferees of the terms and conditions hereof.

      (c)   Except as otherwise described in this Section 6, during the
            Participant's lifetime, the Option is exercisable only by the
            Participant.

7.    Withholding. The Participant may be required to pay to the Company or any
      Affiliate and the Company shall have the right and is hereby authorized to
      withhold, any applicable withholding taxes in respect of the Option, its
      exercise or any payment or transfer under or with respect to the Option
      and to take such other action as may be necessary in the opinion of the
      Committee to satisfy all obligations for the payment of such withholding
      taxes.

8.    Securities Laws. Upon the acquisition of any Shares pursuant to the
      exercise of an Option, the Participant will make or enter into such
      written representations, warranties and agreements as the Committee may
      reasonably request in order to comply with applicable securities laws or
      with this Agreement.

9.    Notices. Any notice necessary under this Agreement shall be addressed to
      the Company in care of its Secretary at the principal executive office of
      the Company and to the Participant at the address appearing in the
      personnel records of the Company for the Participant or to either party at
      such other address as either party hereto may hereafter designate in
      writing to the other. Any such notice shall be deemed effective upon
      receipt thereof by the addressee.

10.   Choice of Law. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
      ACCORDANCE WITH THE LAWS OF BERMUDA, WITHOUT REGARD TO CONFLICTS OF LAWS
      PRINCIPLES.

11.   Option Subject to Plan. By entering into this Agreement the Participant
      agrees and acknowledges that the Participant has received and read a copy
      of the Plan. The Option is subject to the Plan (including without
      limitation the arbitration provision), and the terms and provisions of the
      Plan, as it may be amended from time to time, are hereby incorporated
      herein by reference. In the event of a conflict between any term or
      provision contained herein and a term or provision of the Plan, the
      applicable terms and provisions of the Plan will govern and prevail.

12.   Rights as a Shareholder. The Participant shall have no rights as a
      shareholder, and shall

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      not receive dividends, with respect to any Shares subject to the Option
      until the Option has been exercised and Share certificates have been
      issued to the Participant.

13.   Fiscal Year. If the Company's fiscal year is changed to other than a
      calendar year, the references to calendar year in this Agreement shall be
      adjusted to appropriately reflect the change.

14.   Signature in Counterparts. This Agreement may be signed in counterparts,
      each of which shall be an original, with the same effect as if the
      signatures thereto and hereto were upon the same instrument.

                  IN WITNESS WHEREOF, the parties hereto have executed this
Agreement.

                                       ASPEN INSURANCE HOLDINGS LIMITED

                                       By:
                                           ----------------------------

AGREED AND ACKNOWLEDGED AS
OF THE DATE FIRST ABOVE WRITTEN:

-------------------------------------
Participant

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                                    EXHIBIT A
                                    ---------

                         ROE TARGET FOR 2005 FISCAL YEAR