INVESTMENT MANAGER AGREEMENT

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                                                                 [Exhibit 10.15]

                          INVESTMENT MANAGER AGREEMENT

     THIS AGREEMENT, made as of the 8th day of December, 2005, by and between
VALIDUS REINSURANCE, LTD. (hereinafter called the "Company") and BLACKROCK
(through its subsidiary BlackRock Financial Management, Inc., hereinafter called
the "Manager").

                                   WITNESSETH:

     WHEREAS, the Company has all requisite authority to appoint one or more
investment managers to supervise and direct the investment and reinvestment of a
portion of all of the assets of the Company and of certain subsidiaries of the
Company;

     THEREFORE, for and in consideration of the premises and of the mutual
covenants herein contained, the parties hereby agree as follows:

     1. Appointment and Status as Investment Manager. The Company hereby
appoints the Manager as an "Investment Manager." The Manager does hereby accept
said appointment and by its execution of this Agreement the Manager represents
and warrants that it is registered as an investment adviser under the U.S.
Investment Advisers Act of 1940 (the "Advisers Act"). The Manager does also
acknowledge that it is a fiduciary with respect to the assets under management
and assumes the duties, responsibilities and obligations of a fiduciary with
respect to the services described in Sections 3 through 5 below.

     2. Representations by Company. The Company represents and warrants that (a)
it has all requisite authority to appoint the Manager hereunder, (b) the terms
of the Agreement do not conflict with any obligation by which the Company is
bound, whether arising by contract, operation of law or otherwise and (c) this
Agreement has been duly authorized by appropriate corporate action.

     3. Management Services. The Manager shall be responsible for the investment
and reinvestment of those assets designated by the Company as subject to the
Manager's management (which assets, together with all additions, substitutions
and alterations thereto are hereinafter called the "Account"). The Account may
include all securities and instruments described in Exhibit A or appropriate to
effect the strategies described therein. The Company does hereby delegate to the
Manager all of its powers, duties and responsibilities with regard to such
investment and reinvestment and hereby appoints the Manager as its agent in fact
with full authority to buy, sell or otherwise effect investment transactions
involving the assets in its name and for the Account, including without
limitation, the power to enter into swap, futures, options and other agreements
with counterparties on the Company's behalf as the Manager deems appropriate
from time to time in order to carry out the Manager's responsibilities
hereunder. Said powers, duties and responsibilities shall be exercised
exclusively by the Manager pursuant to and in accordance with its fiduciary
responsibilities and the provisions of this Agreement. In deciding on a proper
investment of the Account, the Manager shall consider the following factors as
communicated in writing to the Manager by the Company from time to time: a) the
investment purposes of the Company, b) the Company's financial needs such as
liquidity, c) applicable laws, d) the Company's investment policies and
guidelines, and e) the

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Account's Investment Guidelines attached as Exhibit A. In addition, in
accordance with the Manager's guidelines in effect from time to time, the
Manager or its agent is authorized, but shall not be required, to vote, tender
or convert any securities in the Account; to execute waivers, consents and other
instruments with respect to such securities; to endorse, transfer or deliver
such securities or to consent to any class action, plan of reorganization,
merger, combination, consolidation, liquidation or similar plan with reference
to such securities; and the Manager shall not incur any liability to the Company
by reason of any exercise of, or failure to exercise, any such discretion in the
absence of gross negligence or bad faith.

     4. Accounting and Reports. At such intervals as shall be mutually agreed
upon between the parties, the Manager shall furnish the Company with appraisals
of the Account, performance tabulations, a summary of purchases and sales and
such other reports as shall be agreed upon from time to time. The Manager shall
also reconcile accounting, transaction and asset-summary data with custodian
reports at times that are mutually agreeable to the Manager and the Company. In
addition, the Manager shall communicate and resolve any significant
discrepancies with the custodian.

     5. Other Services. The Manager shall, on invitation, attend meetings with
representatives of the Company to discuss the position of the Account and the
immediate investment outlook, or shall submit its views in writing as the
Company shall suggest from time to time.

     6. Additional Investment Services; Considerations and Acknowledgments. As
agreed between the parties from time to time, the Manager may provide certain
operating, analytical, and reporting support ("Additional Investment Services")
for those portfolios of the Company managed by the Manager and by other parties.
The Additional Investment Services may include, but are not limited to the
following: (i) establishing appropriate investment mandates and strategies, (ii)
drafting investment policies and guidelines, (iii) supporting the Company's
operations, including custodial assistance, (iv) creating a consolidated risk
reporting platform for the Company, (v) providing asset-liability reporting,
(vi) providing income projections, and (vii) broad and general consulting on
accounting, operational, regulatory, and other strategic issues.

     The Company understands and acknowledges that (a) all Additional Investment
Services require the Manager to exercise good-faith judgments that may
ultimately prove to be erroneous, (b) in connection with providing the
Additional Investment Services, the Manager will make certain assumptions about
the movements of interest rates, volatility of interest rates, movements of
spreads, and the relationship of mortgage prepayments to interest rates, (c) the
Manager's assumptions will not necessarily capture all the characteristics and
risks inherent in the Company's portfolios, and (d) the Manager's assumptions
are based upon information provided to the Manager by the Company or certain of
its third-party vendors that is assumed to be reliable and accurate, but the
Manager does not represent or warrant that it is accurate or complete, and will
not be responsible for verifying the accuracy of any such information.

     7. Compensation. For its investment management services rendered hereunder,
the Manager shall be compensated in accordance with Exhibit B, attached hereto.
If the management of the Account commences or ends at any time other than the
beginning or end of a calendar quarter, the quarterly fee shall be prorated
based on the portion of such calendar quarter during which this Agreement was in
force.

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     8. Custodian. The securities in the Account shall be held by a custodian
duly appointed by the Company and the Manager is authorized to give instructions
to the custodian with respect to all investment deci