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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 decisions regarding the Account.
Nothing contained herein shall be deemed to authorize the Manager to take or
receive physical possession of any of the assets for the Account, it being
intended that sole responsibility for safekeeping thereof (in such investments
as the Manager may direct) and the consummation of all purchases, sales,
deliveries and investments made pursuant to the Manager's direction shall rest
upon the custodian.

     9. Brokerage. The Company hereby delegates to the Manager sole and
exclusive authority to designate the brokers or dealers through whom all
purchases and sales on behalf of the Account will be made. The Manager will
determine the rate or rates, if any, to be paid for brokerage services provided
to the Account. The Manager agrees that securities are to be purchased through
such brokers as, in the Manager's best judgment, shall offer the best
combination of price and execution. The Manager, in seeking to obtain best
execution of portfolio transactions for the Account may consider the quality and
reliability of brokerage services, as well as research and investment
information and other services provided by brokers or dealers. Accordingly, the
Manager's selection of a broker or dealer for transactions for the Account may
take into account such relevant factors as (i) price, (ii) the broker's or
dealer's facilities, reliability and financial responsibility, (iii) when
relevant, the ability of the broker to effect securities transactions,
particularly with regard to such aspects as timing, order size and execution of
the order, (iv) the broker's or dealer's recordkeeping capabilities and (v) the
research and other services provided by such broker or dealer to the Manager
which are expected to enhance its general portfolio management capabilities
(collectively, "Research"), notwithstanding that the Account may not be the
exclusive beneficiary of such Research.

     10. Confidential Information. All information regarding operations and
investments of the Company shall be regarded as confidential by the Manager. The
terms of this Agreement, including the Exhibits hereto, also shall be regarded
as confidential by the Company and the Manager and shall not be disclosed to any
third party except with the consent of both parties or if a party becomes
legally compelled (by deposition, interrogatory, request for documents,
subpoena, civil investigative demand or similar process) to do so, and then only
to the extent of such legal compulsion; provided, further, that in the event of
legal compulsion to disclose the terms hereof, the party subject to such legal
process shall (a) first notify the other party of such legal process, unless
such notice is prohibited by statute, rule or court order, (b) attempt to obtain
the other party's consent to such disclosure, and (c) in the event consent is
not given, agree to permit a motion to quash, or other similar procedural step,
to frustrate the production or publication of information. In making any
disclosure under such legal process, a disclosing party agrees to use all
reasonable efforts to preserve the confidential nature of such information.

     11. Directions to the Manager. All directions by or on behalf of the
Company to the Manager shall be in writing signed by:

<TABLE>
<CAPTION>
Name           Title
----           -----
<S>            <C>
Ed Noonan      Chairman
George Reeth   Deputy Chairman
</TABLE>

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     The Manager shall be fully protected in relying upon any direction in
accordance with the previous paragraph with respect to any instruction,
direction or approval of the Company, and shall be so protected also in relying
upon a certification duly executed on behalf of the Company as to the names of
persons authorized to act for it and in continuing to rely upon such
certification until notified by the Company to the contrary.

     The Manager shall be fully protected in acting upon any instrument,
certificate or paper believed by it to be genuine and to be signed or presented
by the proper persons or to any statement contained in any such writing and may
accept the same as conclusive evidence of the truth and accuracy of the
statements therein contained.

     12. Liabilities of the Manager and the Company. The Company acting in good
faith shall not be liable for any act or omission of the Manager in connection
with the Manager's discharge of its duties; provided, however, this limitation
shall not act to relieve the Company from any responsibility or liability for
any fiduciary responsibility, obligation or duty. The Manager, its officers,
directors and employees, acting in good faith shall not be liable and shall be
indemnified by the Company against any and all losses, damages, costs, expenses
(including reasonable attorneys' fees), liabilities, claims and demands
(collectively, "Losses"), for any action, omission, information or
recommendation in connection with this Agreement, except in the case of the
Manager's or such officer's, director's or employee's actual misconduct, gross
negligence, willful violation of any applicable statute or reckless disregard
for its duties and except as further limited in the paragraph immediately below;
provided, however, this limitation shall not act to relieve the Manager, its
officers, directors and employees from any responsibility or liability for any
responsibility, obligation or duty which the Manager or such officer, director
or employee may have under any federal securities act; and provided, further,
however, that to the extent any limitations or restrictions contained in the
Investment Guidelines are not adhered to as a result of changes in market value,
additions to or withdrawals from the Account, portfolio rebalancing or other
nonvolitional acts of the Manager, the Manager shall not be liable to the
Company.

     The Company understands that in connection with the Additional Investment
Services provided by the Manager that (i) the Manager is not serving in an
investment advisory capacity, or making any recommendations or soliciting any
action based upon its analyses with respect to those portfolios of the Company
not managed by the Manager and (ii) the Company will be solely responsible for
any judgments as to valuation and the purchase and sale of its portfolio
securities (other than in the case of the Account). Accordingly, the Manager
will not be responsible, and have no liability, for any conclusions drawn by the
Company with respect to its portfolio securities, notwithstanding that such
conclusions may, in part, be based upon information provided by the Manager in
connection with the Additional Investment Services.

     13. Non-Exclusive Management. The Company understands that the Manager will
continue to furnish investment management and advisory services to others, and
that the Manager shall be at all times free, in its discretion, to make
recommendations to others which may be the same as, or may be different from
those made to the Account. The Company further understands that the Manager, its
affiliates, and any officer, director, stockholder, employee or any member of
their families may or may not have an interest in the securities whose purchase
and sale the Manager may recommend. Actions with respect to securities of the
same kind may be the same as or different from

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the action which the Manager, or any of its affiliates, or any officer,
director, stockholder, employee or any member of their families, or other
investors may take with respect thereto.

     14. Aggregation and Allocation of Orders. The Company acknowledges that
circumstances may arise under which the Manager determines that, while it would
be both desirable and suitable that a particular security or other investment be
purchased or sold for the account of more than one of the Manager's clients'
accounts, there is a limited supply or demand for the security or other
investment. Under such circumstances, the Company acknowledges that, while the
Manager will seek to allocate the opportunity to purchase or sell that security
or other investment among those accounts on an equitable basis, the Manager
shall not be required to assure equality of treatment among all of its clients
(including that the opportunity to purchase or sell that security or other
investment will be proportionally allocated among those clients according to any
particular or predetermined standards or criteria). Where, because of prevailing
market conditions, it is not possible to obtain the same price or time of
execution for all of the securities or other investments purchased or sold for
the Account, the Manager may average the various prices and charge or credit the
Account with the average price.

     15. Conflict of Interest. The Company agrees that the Manager may refrain
from rendering any advice or services concerning securities of companies of
which any of the Manager's, or affiliates of the Manager's officers, directors,
or employees are directors or officers, or companies as to which the Manager or
any of the Manager's affiliates or the officers, directors and employees of any
of them has any substantial economic interest or possesses material non-public
information, unless the Manager either determines in good faith that it may
appropriately do so without disclosing such conflict to the Company or discloses
such conflict to the Company prior to rendering such advice or services with
respect to the Account.

     From time to time, when determined by the Manager in its capacity of a
fiduciary to be in the best interest of the Company, the Account may purchase
securities from or sell securities to another account managed by the Manager at
prevailing market levels in accordance with the procedures under Rule 17a-7(b)
of the U.S. Investment Company Act of 1940 and other applicable law.

     16. Effective Period of Agreement and Amendments. This Agreement shall
become effective on the date hereof. Any amendment to this Agreement shall be
written and signed by both parties to the Agreement. No such amendment shall be
effective to permit the use of the Account or any part thereof for any purpose
not authorized by the Company's charter.

     17. Resignation or Removal of the Manager. The Manager may be removed by
the Company or may resign upon 30 days' notice in writing. On the effective date
of the removal or resignation of the Manager or as close to such date as is
reasonably possible, the Manager shall provide the Company with a final report
containing the same information as paragraph 4 above.

     18. Assignment. No assignment (as that term is defined in the Advisers Act)
of this Agreement by the Manager may be made without the consent of the Company,
and any such assignment made without such consent shall be null and void for all
purposes. Subject to the foregoing, this Agreement shall inure to the benefit of
and be binding upon the parties hereto, their successors and permitted assigns.

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     19. Severable. Any term or provision of this Agreement which is invalid or
unenforceable in any applicable jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such invalidity or unenforceability without
rendering invalid or unenforceable remaining terms or provisions of the
Agreement in any jurisdiction.

     20. Applicable Law. To the extent not inconsistent with applicable U.S.
federal law, this Agreement shall be construed pursuant to, and shall be
governed by, the laws of the state of New York.

     21. Investment Manager Brochure. The Company hereby acknowledges that it
has received from the Manager a copy of the Manager's Form ADV, Part II, at
least forty-eight hours prior to entering into this Agreement.

     22. Web-site. The Manager, at the Company's request, will provide access to
its account information electronically, via the world wide web, based upon the
Company's use of a BlackRock issued user id and password. The Company
acknowledges and agrees the world wide web is a continually growing medium and
the Manager does not make any warranty regarding the security related to the
world wide web. The Company must be aware there is no absolute guaranteed system
or technique to fully secure information made available over the web. The
Company agrees that it will not share its user id, password and access to
information provided electronically with any third party.

     23. Notices. All notices required or permitted to be sent under this
Agreement shall be sent, if to the Manager:

                        c/o BlackRock, Inc.
                        40 East 52nd Street
                        New York, NY 10022
                        Attention: Robert Connolly, General Counsel
                        or by facsimile to (212) 810-3744

     if to the Company: Validus Reinsurance, Ltd.
                        Suite 1790
                        48 Par-la-Ville Road
                        Hamilton, HM 11 Bermuda
                        Attention: Ed Noonan
                        or by facsimile to: 441-278-9090

or such other name or address as may be given in writing to the other party. All
notices hereunder shall be sufficient if delivered by facsimile or overnight
mail. Any notices shall be deemed given only upon actual receipt.

     24. Counterparts. This Agreement may be executed in counterparts, each of
which shall be an original but all of which together shall constitute one
agreement.

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     25. Use of Futures. Pursuant to an exemption from the U.S. Commodity
Futures Trading Commission (the "Commission") in connection with accounts of
qualified eligible persons, this Agreement is not required to be, and has not
been, filed with the Commission. The Commission does not pass upon the merits of
participating in a trading program or upon the adequacy or accuracy of commodity
trading advisor disclosure. Consequently, the Commission has not reviewed or
approved this Agreement.

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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the date first above written.

VALIDUS REINSURANCE, LTD.


By:
    ---------------------------------
Name:
      -------------------------------
Title:
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BLACKROCK
(through its subsidiary BlackRock Financial Management, Inc.)


By:
    ---------------------------------
Name:
      -------------------------------
Title:
       ------------------------------