Exhibit 3.18

                       LIMITED LIABILITY COMPANY AGREEMENT

                                       OF

                       UBS PREFERRED FUNDING COMPANY LLC V

                  This LIMITED LIABILITY COMPANY AGREEMENT (this "Agreement") of
UBS Preferred Funding Company LLC V. is entered into by UBS AG, a bank organized
under the laws of Switzerland (the "Member").

                  The Member, by execution of this Agreement, hereby forms a
limited liability company pursuant to and in accordance with the Delaware
Limited Liability Company Act (6 Del.C. Section 18-101, et seq.), as amended
from time to time (the "Act"), and hereby agrees as follows:

                  1.       Name. The name of the limited liability company
formed hereby is UBS Preferred Funding Company LLC V. (the "Company").

                  2.       Certificates. Jonathon A. Redwood, as an authorized
person within the meaning of the Act, shall execute, deliver and file the
Certificate of Formation with the Secretary of State of the State of Delaware.
Upon the filing of the Certificate of Formation with the Secretary of State of
the State of Delaware, his powers as an authorized person shall cease and the
Member shall thereafter be designated as an authorized person within the meaning
of the Act. The Member or an Officer shall execute, deliver and file any other
certificates (and any amendments and/or restatements thereof) necessary for the
Company to qualify to do business in a jurisdiction in which the Company may
wish to conduct business.

                  3.       Purpose. The Company is formed for the object and
purpose of, and the nature of the business to be conducted and promoted by the
Company is, engaging in any lawful act or activity for which limited liability
companies may be formed under the Act.

                  4.       Powers.

                  (a)      In furtherance of its purposes, but subject to all
of the provisions of this Agreement, the Company shall have the power and is
hereby authorized to:

                           (i)      acquire by purchase, lease, contribution of
         property or otherwise, own, hold, sell, convey, transfer or dispose of
         any real or personal property which may be necessary, convenient or
         incidental to the accomplishment of the purpose of the Company;

                           (ii)     act as a trustee, executor, nominee, bailee,
         director, officer, agent or in some other fiduciary capacity for any
         person or entity and to exercise all of the powers, duties, rights and
         responsibilities associated therewith;



                           (iii)    take any and all actions necessary,
         convenient or appropriate as trustee, executor, nominee, bailee,
         director, officer, agent or other fiduciary, including the granting or
         approval of waivers, consents or amendments of rights or powers
         relating thereto and the execution of appropriate documents to evidence
         such waivers, consents or amendments;

                           (iv)     operate, purchase, maintain, finance,
         improve, own, sell, convey, assign, mortgage, lease or demolish or
         otherwise dispose of any real or personal property which may be
         necessary, convenient or incidental to the accomplishment of the
         purposes of the Company;

                           (v)      borrow money and issue evidences of
         indebtedness in furtherance of any or all of the purposes of the
         Company, and secure the same by mortgage, pledge or other lien on the
         assets of the Company;

                           (vi)     invest any funds of the Company pending
         distribution or payment of the same pursuant to the provisions of this
         Agreement;

                           (vii)    prepay in whole or in part, refinance,
         recast, increase, modify or extend any indebtedness of the Company and,
         in connection therewith, execute any extensions, renewals or
         modifications of any mortgage or security agreement securing such
         indebtedness;

                           (viii)   enter into, perform and carry out contracts
         of any kind, including, without limitation, contracts with any person
         or entity affiliated with the Member, necessary to, in connection with,
         convenient to, or incidental to the accomplishment of the purposes of
         the Company;

                           (ix)     employ or otherwise engage employees,
         managers, contractors, advisors, attorneys and consultants and pay
         reasonable compensation for such services;

                           (x)      enter into partnerships, limited liability
         companies, trusts, associations, corporations or other ventures with
         other persons or entities in furtherance of the purposes of the
         Company; and

                           (xi)     do such other things and engage in such
         other activities related to the foregoing as may be necessary,
         convenient or incidental to the conduct of the business of the Company,
         and have and exercise all of the powers and rights conferred upon
         limited liability companies formed pursuant to the Act.

                  (b)      Notwithstanding anything in this Agreement to the
contrary, without the need for consent of the Member, any Director or any
Officer, the Company is authorized to:

                           (i)      issue noncumulative company preferred
         securities and invest such proceeds in subordinated notes issued by the
         Cayman Islands branch of the Member;

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                           (ii)     issue common limited liability company
         interests; and

                           (iii)    issue a prospectus pursuant to which the
         securities listed in (i) and (ii) may be offered, and negotiate and
         execute an underwriting agreement pursuant to which the securities
         listed in (i) may be distributed; and the Member or any Officer may, on
         behalf of the Company, execute and deliver, and cause the Company (A)
         to perform its obligations under, (B) to satisfy any conditions
         required to be satisfied by the Company as a condition precedent to the
         effectiveness of, and (3) to take such other actions as such Member or
         Officer may deem appropriate with respect to such documents.

                  5.       Principal Business Office. The principal business
office of the Company shall be located at such location as may hereafter be
determined by the Member.

                  6.       Registered Office. The address of the registered
office of the Company in the State of Delaware is The Corporation Trust Company,
Corporation Trust Center, 1209 Orange Street, Wilmington, Delaware 19801.

                  7.       Registered Agent. The name and address of the
registered agent of the Company for service of process on the Company in the
State of Delaware is The Corporation Trust Company, Corporation Trust Center,
1209 Orange Street, Wilmington, Delaware 19801.

                  8.       Members. The name and the mailing address of the
Member is set forth in the records of the Company.

                  9.       Limited Liability. Except as otherwise provided by
the Act, the debts, obligations and liabilities of the Company, whether arising
in contract, tort or otherwise, shall be solely the debts, obligations and
liabilities of the Company, and the Member shall not be obligated personally for
any such debt, obligation or liability of the Company solely by reason of being
a member of the Company.

                  10.      Capital Contributions. The Member is deemed admitted
as the Member of the Company upon its execution and delivery of this Agreement.
The Member will contribute $100.00 to the Company.

                  11.      Additional Contributions. The Member is not required
to make any additional capital contribution to the Company. However, a Member
may make additional capital contributions to the Company with the written
consent of the Member.

                  12.      Allocation of Profits and Losses. The Company's
profits and losses shall be allocated to the Member.

                  13.      Distributions. Distributions shall be made to the
Member at the times and in the aggregate amounts determined by the Member.
Notwithstanding any provision to the contrary contained in this Agreement, the
Company shall not make a distribution to any Member on account of its interest
in the Company if such distribution would violate Section 18-607 of the

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Act or other applicable law.

                  14.      Management. In accordance with Section 18-402 of the
Act, management of the Company shall be vested in the Member. The Member shall
have the power to do any and all acts necessary, convenient or incidental to or
for the furtherance of the purposes described herein, including all powers,
statutory or otherwise, possessed by members of a limited liability company
under the laws of the State of Delaware. The Member has the authority to bind
the Company.

                  15.      Directors and Officers. The Member may, from time to
time as it deems advisable, appoint directors of the Company ( the "Directors")
and officers of the Company (the "Officers") and assign in writing titles
(including, without limitation, President, Vice President, Secretary, and
Treasurer) to any such person. Unless the Member decides otherwise, if the title
is one commonly used for officers of a business corporation formed under the
Delaware General Corporation Law, the assignment of such title shall constitute
the delegation to such person of the authorities and duties that are normally
associated with that office. Any delegation pursuant to this Section 15 may be
revoked at any time by the Member.

                  16.      Other Business. The Member may engage in or possess
an interest in other business ventures (unconnected with the Company) of every
kind and description, independently or with others. The Company shall not have
any rights in or to such independent ventures or the income or profits therefrom
by virtue of this Agreement.

                  17.      Exculpation and Indemnification. No Member, Director
or Officer shall be liable to the Company, or any other person or entity who has
an interest in the Company, for any loss, damage or claim incurred by reason of
any act or omission performed or omitted by such Member, Director or Officer in
good faith on behalf of the Company and in a manner reasonably believed to be
within the scope of the authority conferred on such Member or Officer by this
Agreement, except that a Member, Director or Officer shall be liable for any
such loss, damage or claim incurred by reason of such Member's, Director's or
Officer's willful misconduct. To the fullest extent permitted by applicable law,
a Member, Director or Officer shall be entitled to indemnification from the
Company for any loss, damage or claim incurred by such Member, Director or
Officer by reason of any act or omission performed or omitted by such Member,
Director or Officer in good faith on behalf of the Company and in a manner
reasonably believed to be within the scope of the authority conferred on such
Member, Director or Officer by this Agreement, except that no Member, Director
or Officer shall be entitled to be indemnified in respect of any loss, damage or
claim incurred by such Member, Director or Officer by reason of willful
misconduct with respect to such acts or omissions; provided, however, that any
indemnity under this Section 17 shall be provided out of and to the extent of
Company assets only, and no Member shall have personal liability on account
thereof.

                  18.      Assignments. A Member may assign in whole or in part
its limited liability company interest with the written consent of the Member.
If a Member transfers all of its interest in the Company pursuant to this
Section, the transferee shall be admitted to the Company upon its execution of
an instrument signifying its agreement to be bound by the terms and conditions
of this Agreement. Such admission shall be deemed effective immediately prior

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to the transfer, and, immediately following such admission, the transferor
Member shall cease to be a member of the Company.

                  19.      Resignation. A Member may resign from the Company
with the written consent of the Member. If a Member is permitted to resign
pursuant to this Section, an additional member shall be admitted to the Company,
subject to Section 20, upon its execution of an instrument signifying its
agreement to be bound by the terms and conditions of this Agreement. Such
admission shall be deemed effective immediately prior to the resignation, and,
immediately following such admission, the resigning Member shall cease to be a
member of the Company.

                  20.      Admission of Additional Members. One (1) or more
additional members of the Company may be admitted to the Company with the
written consent of the Member.

                  21.      Dissolution.

                           (a)      The Company shall dissolve, and its affairs
         shall be wound up upon the first to occur of the following: (i) the
         written consent of the Member, (ii) the retirement, resignation or
         dissolution of the Member or the occurrence of any other event which
         terminates the continued membership of the Member in the Company unless
         the business of the Company is continued in a manner permitted by the
         Act, or (iii) the entry of a decree of judicial dissolution under
         Section 18-802 of the Act.

                           (b)      The bankruptcy of the Member will not cause
         the Member to cease to be a member of the Company and upon the
         occurrence of such an event, the business of the Company shall continue
         without dissolution.

                           (c)      In the event of dissolution, the Company
         shall conduct only such activities as are necessary to wind up its
         affairs (including the sale of the assets of the Company in an orderly
         manner), and the assets of the Company shall be applied in the manner,
         and in the order of priority, set forth in Section 18-804 of the Act.

                  22.      Separability of Provisions. Each provision of this
Agreement shall be considered separable and if for any reason any provision or
provisions herein are determined to be invalid, unenforceable or illegal under
any existing or future law, such invalidity, unenforceability or illegality
shall not impair the operation of or affect those portions of this Agreement
which are valid, enforceable and legal.

                  23.      Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be deemed an original of this
Agreement.

                  24.      Entire Agreement. This Agreement constitutes the
entire agreement of the Member with respect to the subject matter hereof.

                  25.      Governing Law. This Agreement shall be governed by,
and construed under, the laws of the State of Delaware (without regard to
conflict of laws principles), all rights

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and remedies being governed by said laws.

                  26.      Amendments. This Agreement may not be modified,
altered, supplemented or amended except pursuant to a written agreement executed
and delivered by the Member.

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                  IN WITNESS WHEREOF, the undersigned, intending to be legally
bound hereby, has duly executed this Agreement as of the 12th day of December,
2002. Pursuant to Section 18-201(d) of the Act, this Agreement shall be
effective as of December 12, 2002.

                                                UBS AG

                                                By:  /s/ Robert Dinerstein
                                                     ---------------------------
                                                     Name:   Robert Dinerstein
                                                     Title:  Managing Director

                                                By:  /s/ Robert Mills
                                                     ---------------------------
                                                     Name:   Robert Mills
                                                     Title:  Chief Financial
                                                             Officer -- Americas
                                                             and Regional Chief
                                                             Operating Officer

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