EXHIBIT 10.18

        AMENDMENT NO. 1 TO FACULTATIVE QUOTA SHARE REINSURANCE AGREEMENT


                AMENDMENT NO. 1 dated as of August 4, 2006 by and between XL
FINANCIAL ASSURANCE LTD., a company incorporated under the laws of Bermuda
(hereinafter referred to as "Ceding Company") and XL INSURANCE (BERMUDA) LTD, a
company incorporated under the laws of Bermuda, (hereinafter referred to as
"Reinsurer").

                WHEREAS, the Ceding Company and the Reinsurer entered into a
facultative quota share reinsurance agreement effective August 17, 2001
("Facultative Agreement") attached hereto as Exhibit A pursuant to which the
Reinsurer agreed to cede to the Reinsurer, on a quota share basis, risk in
respect of Policies issued by the Ceding Company which cessions the Reinsurer
may accept or reject in its sole discretion;

                WHEREAS, the Ceding Company and the Reinsurer wish to amend the
Facultative Agreement to amend the terms of Article IV of the Facultative
Agreement provisions.

                Section 1. DEFINITIONS. Except as otherwise defined in this
Amendment No. 1, terms defined in the Facultative Agreement are used herein as
defined therein.

                Section 2. AMENDMENTS. The Facultative Agreement is hereby
amended as follows:

                2.01.   References in the Facultative Agreement (including
        references to the Facultative Agreement as amended hereby) to "this
        Agreement" (and indirect references such as "hereunder", "hereby",
        "herein" and "hereof") shall be deemed to be references to the
        Facultative Agreement as amended hereby.

                2.02.   Section 1.9 of Article IV is amended to add the
        following provisions at the end of said section:

        "Further, the Reinsurer shall have the right to terminate this
        Facultative Quota Share Reinsurance Agreement at any time upon not less
        than days prior written or electronic notice to the Ceding Company upon
        the occurrence of either one or the following events:

        (i)     a "Ceding Company Change in Control" (as defined below) and,

        (ii)    a downgrade of the Ceding Company's Standard & Poor's financial
        strength rating below AA or a downgrade of the Ceding Company's Moody's
        financial strength rating below Aa2.

For the purposes of this Facultative Quota Share Reinsurance Agreement, a
"Ceding Company Change in Control" will be deemed to occur in the event that (i)
the ownership in Security Capital Assurance Ltd ("SCA") by the Reinsurer or by
the Reinsurer and its affiliates, falls below

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thirty five percent (35%) or (ii) SCA's direct or indirect ownership interest in
the issued and outstanding shares of voting securities of the Ceding Company
falls below ninety five (95%)."

                Section 3. CONDITIONS PRECEDENT. The amendment to the
Facultative Agreement set forth in Section 2 above shall become effective, as of
the date hereof, upon the satisfaction of the following condition precedent:

                3.01. EXECUTION. This Amendment No. 1 shall have been executed
        and delivered by each of the Ceding Company and the Reinsurer.

                Section 4. MISCELLANEOUS. Except as herein provided, the
Facultative Agreement shall remain unchanged and in full force and effect. This
Amendment No. 1 may be executed in any number of counterparts, all of which
taken together shall constitute one and the same amendatory instrument and any
of the parties hereto may execute this Amendment No. 1 by signing any such
counterpart. This Amendment No. 1 shall be governed by, and construed in
accordance with, the laws of Bermuda.

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The parties hereto have caused this Amendment No. 1 to be duly executed and
delivered as of the day and year first above written.


SIGNED for and on behalf of
XL INSURANCE (BERMUDA) LTD



By:
Name:
Title:



SIGNED for and on behalf of
XL FINANCIAL ASSURANCE LTD.



By:
Name:
Title: