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                                                                    Exhibit 4(k)


                             SUB-ADVISORY AGREEMENT


     Agreement made as of September 16, 2002 between UBS GLOBAL ASSET
MANAGEMENT (US) INC. ("UBS Global AM"), a Delaware corporation, and GE ASSET
MANAGEMENT INCORPORATED ("Sub-Adviser"), a Delaware Corporation (the
"Agreement").

                                    RECITALS

     (1)  UBS Global AM has entered into a Management Agreement dated
June 15, 1995 ("Management Agreement") with UBS PACE Select Advisors Trust
(formerly known as Managed Accounts Services Portfolio Trust ("Trust")), an
open-end management investment company registered under the Investment Company
Act of 1940, as amended ("1940 Act"), with respect to UBS PACE LARGE CO GROWTH
EQUITY INVESTMENTS ("Portfolio");

     (2)  UBS Global AM desires to retain the Sub-Adviser to furnish certain
investment advisory services to UBS Global AM and the Portfolio and to manage
such portion of the Portfolio as UBS Global AM shall from time to time direct;
and

     (3)  The Sub-Adviser is willing to furnish such services;

     NOW, THEREFORE, in consideration of the premises and mutual covenants
herein contained, UBS Global AM and the Sub-Adviser agree as follows:

     1.   APPOINTMENT. UBS Global AM hereby appoints the Sub-Adviser as an
investment sub-adviser with respect to the Portfolio for the period and on the
terms set forth in this Agreement. The Sub-Adviser accepts that appointment and
agrees to render the services herein set forth, for the compensation herein
provided.

     2.   DUTIES AS SUB-ADVISER.

     (a)  Subject to the supervision and direction of the Trust's Board of
Trustees (the "Board") and review by UBS Global AM, and any written guidelines
adopted by the Board or UBS Global AM, the Sub-Adviser will provide a continuous
investment program for all or a designated portion of the assets ("Segment") of
the Portfolio, including investment research and discretionary management with
respect to all securities and investments and cash equivalents in the Portfolio
or Segment. The Sub-Adviser will determine from time to time what investments
will be purchased, retained or sold by the Portfolio or Segment. The Sub-Adviser
will be responsible for placing purchase and sell orders for investments and for
other related transactions for the Portfolio or Segment. The Sub-Adviser will be
responsible for voting proxies of issuers of securities held by the Portfolio or
Segment. The Sub-Adviser understands that the Portfolio's assets need to be
managed so as to permit the Portfolio to qualify or to continue to qualify as a
regulated investment company under Subchapter M of the Internal Revenue Code, as
amended ("Code"). The Sub-Adviser will provide services under this Agreement in
accordance with the Portfolio's investment objective,

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policies and restrictions as stated in the Trust's currently effective
registration statement under the 1940 Act, and any amendments or supplements
thereto ("Registration Statement"). UBS Global AM shall notify the Sub-Adviser
before proposing to make any changes relating to the Portfolio's investment
objective, policies and restrictions, as set forth in the Registration
Statement.

     (b)  The Sub-Adviser shall take all actions that it considers necessary to
implement, with respect to the Segment of the Portfolio that it manages, the
investment objectives and policies of the Portfolio, and in particular, to place
all orders for the purchase or sale of securities or other investments for the
Portfolio with brokers or dealers selected by it, and to that end, the
Sub-adviser is authorized as agent of the Portfolio to give instructions to the
Portfolio's custodian as to deliveries of securities or other investments and
payments of cash for the account of the Portfolio. The Sub-Adviser agrees that,
in placing orders with brokers, it will obtain the best net result in terms of
price and execution; provided that, on behalf of the Portfolio, the Sub-Adviser
may, in its discretion, use brokers that provide the Sub-Adviser with research,
analysis, advice and similar services to execute portfolio transactions on
behalf of the Portfolio, and the Sub-Adviser may pay to those brokers in return
for brokerage and research services a higher commission than may be charged by
other brokers, subject to the Sub-Adviser's determination in good faith that
such commission is reasonable in terms either of the particular transaction or
of the overall responsibility of the Sub-Adviser to the Portfolio and its other
clients and that the total commissions paid by the Portfolio or Segment will be
reasonable in relation to the benefits to the Portfolio or Segment over the long
term. In no instance will portfolio securities be purchased from or sold to UBS
Global AM or the Sub-Adviser, or any affiliated person thereof, except in
accordance with the federal securities laws and the rules and regulations
thereunder. The Sub-Adviser may aggregate sales and purchase orders with respect
to the assets of the Portfolio or Segment with similar orders being made
simultaneously for other accounts advised by the Sub-Adviser or its affiliates.
Whenever the Sub-Adviser simultaneously places orders to purchase or sell the
same security on behalf of the Portfolio and one or more other accounts advised
by the Sub-Adviser, the orders will be allocated as to price and amount among
all such accounts in a manner believed to be equitable over time to each
account. UBS Global AM recognizes that in some cases this procedure may
adversely affect the results obtained for the Portfolio or Segment.

     Subject to the Sub-Adviser's obligations to seek best execution, UBS Global
AM agrees that the Sub-Adviser, in its sole discretion, may place transactions
on behalf of the Portfolio and the Trust with any broker-dealer, which is deemed
to be an affiliate of UBS Global AM, the Sub-Adviser or with any other entity
that serves as investment adviser or sub-adviser to the Portfolio, or which is
otherwise affiliated with the Portfolio in accordance with the 1940 Act (the
"Affiliated Broker-Dealers") so long as such transactions are effected in
conformity with the requirements (including any applicable exemptions and
administrative interpretations set forth in Part II of the Sub-Adviser's Form
ADV Registration Statement on file with the Securities and Exchange Commission
("Form ADV")) of Section 11(a)(1)(H) of the Securities Exchange Act of 1934 (the
"1934 Act"). In all such dealings, the Affiliated Broker-Dealers shall be
authorized and entitled to retain any commissions, remuneration or profits which
may be made in such transactions and shall not be liable to account for the same
to UBS Global AM, the Portfolio or the Trust.

     UBS Global AM further authorizes the Sub-adviser and its Affiliated
Broker-Dealers to execute agency cross transactions (the "Cross Transactions")
on behalf of the Portfolio and the

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Trust. Cross Transactions are transactions; which may be effected by the
Affiliated Broker-Dealers acting for both the Portfolio or the Trust and the
counterparty to the transaction. Cross Transactions enable the Sub-adviser to
purchase or sell a block of securities for the Portfolio or the Trust at a set
price and possibly avoid an unfavorable price movement that may be created
through entrance into the market with such purchase or sale order. As such, the
Sub-adviser believes that Cross Transactions can provide meaningful benefits for
the Portfolio and the Trust and its clients generally. UBS Global AM, the
Portfolio and the Trust should be aware, however, that in a Cross Transaction an
Affiliated Broker-Dealer will be receiving commissions from both sides of the
trade and, therefore, there is a potentially conflicting division of loyalties
and responsibilities.

     (c)  The Sub-Adviser will maintain all books and records required to be
maintained pursuant to Rule 31a-1(b)(2)(ii), (3), (5), (6), (7), (9) and (10)
under the 1940 Act and the rules and regulations promulgated thereunder with
respect to transactions by the Sub-Adviser on behalf of the Portfolio or
Segment, and will furnish the Board and UBS Global AM with such periodic and
special reports as the Board or UBS Global AM reasonably may request. In
compliance with the requirements of Rule 31a-3 under the 1940 Act, the
Sub-Adviser hereby agrees that all records which it maintains for the Portfolio
are the property of the Trust, agrees to preserve for the periods prescribed by
Rule 31a-2 under the 1940 Act any records that it maintains for the Portfolio
and that are required to be maintained by Rule 31a-1 under the 1940 Act, and
further agrees to surrender promptly to the Trust any records which it maintains
for the Portfolio upon request by the Trust.

     (d)  At such times as shall be reasonably requested by the Board or UBS
Global AM, the Sub-Adviser will provide the Board and UBS Global AM with
economic and investment analyses and reports as well as quarterly reports
setting forth the performance of the Portfolio or Segment and make available to
the Board and UBS Global AM any economic, statistical and investment services
that the Sub-Adviser normally makes available to its institutional or other
customers.

     (e)  In accordance with procedures adopted by the Board, as amended from
time to time, the Sub-Adviser is responsible for assisting in the fair valuation
of all portfolio securities in the Portfolio or Segment and will use its
reasonable efforts to arrange for the provision of a price or prices from one or
more parties independent of the Sub-Adviser for each portfolio security for
which the custodian does not obtain prices in the ordinary course of business
from an automated pricing service.

     3.   FURTHER DUTIES.

     (a)  In all matters relating to the performance of this Agreement, the
Sub-Adviser will seek to act in conformity with the Trust's Trust Instrument,
By-Laws and Registration Statement and with the written instructions and written
directions of the Board and UBS Global AM; and will comply with the requirements
of the 1940 Act, and the Investment Advisers Act of 1940, as amended ("Advisers
Act"), and the rules under each, the Code, and all other federal and state laws
and regulations applicable to the Trust and the Portfolio, with respect to the
Segment of the Portfolio that it manages. UBS Global AM agrees to provide to the
Sub-Adviser copies of the Trust's Trust Instrument, By-Laws, Registration
Statement, written instructions and directions of the Board and UBS Global AM,
and any amendments or supplements to any of these materials as soon as
practicable after such materials become available; and further agrees to
identify to the Sub-Adviser in writing any investments that are restricted or
prohibited by the Fund, including those

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issued by entities that are affiliated persons as defined in the 1940 Act, and
any broker-dealers, which are affiliated with UBS Global AM (in addition to UBS
PaineWebber Incorporated and UBS Global AM itself). (b) UBS Global AM and the
Sub-Adviser agree that neither of them nor any of their affiliates, will in any
way refer directly or indirectly to their relationship with one another or any
of their respective affiliates in offering, marketing or other promotional
materials without the express consent of the other, which consent will be
promptly provided and not unreasonably withheld. Any offering, marketing or
promotional material submitted for approval will be deemed to be "consented to"
if a response is not received within 15 days of receipt of the material by a
party.

     4.   EXPENSES. During the term of this Agreement, the Sub-Adviser will bear
all expenses incurred by it in connection with its services under this
Agreement. The Sub-Adviser shall not be responsible for any expenses incurred by
the Trust, the Portfolio or UBS Global AM.

     5.   COMPENSATION.

     (a)  For the services provided and the expenses assumed by the Sub-Adviser
pursuant to this Agreement, UBS Global AM, not the Portfolio, will pay to the
Sub-Adviser a fee, computed daily and payable monthly, at an annual rate of
0.30% of the average daily net assets of the Portfolio or Segment allocated to
its management (computed in the manner specified in the Management Agreement),
and will provide the Sub-Adviser with a schedule showing the manner in which the
fee was computed. If the Sub-Adviser is managing a Segment, its fees will be
based on the value of the assets of the Portfolio within the Sub-Adviser's
Segment.

     (b)  The fee shall be accrued daily and payable monthly to the Sub-Adviser
on or before the last business day of the next succeeding calendar month.

     (c)  If this Agreement becomes effective or terminates before the end of
any month, the fee for the period from the effective date to the end of the
month or from the beginning of such month to the date of termination, as the
case may be, shall be pro-rated according to the proportion that such period
bears to the full month in which such effectiveness or termination occurs.

     7.   LIMITATION OF LIABILITY.

     (a)  The Sub-Adviser, its officers and directors, and any person who
controls the Sub-adviser within the meaning of Section 15 of the Securities Act
of 1933, as amended, shall not be liable for any error of judgment or mistake of
law or for any loss suffered by the Portfolio, the Trust or its shareholders or
by UBS Global AM in connection with the matters to which this Agreement relates,
except a loss resulting from willful misfeasance, bad faith or gross negligence
on its part in the performance of its duties or from reckless disregard by it of
its obligations and duties under this Agreement.

     (b)  In no event will the Sub-Adviser have any responsibility or liability
for any other series of the Trust, for any portion of the Portfolio not managed
by the Sub-Adviser or for the acts or omissions of any other current, prior or
interim adviser or sub-adviser to the Trust or Portfolio.

     In particular, in the event the Sub-Adviser shall manage only a portion of
the Portfolio's investments, the Sub-Adviser shall have no responsibility for
the Portfolio's being in violation of

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any applicable law or regulation or investment policy or restriction applicable
to the Portfolio as a whole or for the Portfolio's failing to qualify as a
regulated investment company under the Code, if the securities and other
holdings of the Segment of the Portfolio managed by the Sub-Adviser are such
that such Segment would not be in such violation or fail to so qualify if such
Segment were deemed a separate series of the Trust or a separate "regulated
investment company" under the Code.

     (c)  In no event will the Sub-Adviser have any responsibility or liability
for any investment transactions recommended or effected before the effective
date of this Agreement, or for any violations or alleged violations of
applicable law and regulation or investment policy or restriction applicable to
the Portfolio to the extent caused by UBS Global AM's failure to provide timely
written information as set forth in paragraph 3 above or to the extent caused by
an Affiliated Broker-Dealer's failure to comply with the requirements of
Section 11(a)(1)(H) of the 1934 Act..

     Nothing in this section shall be deemed a limitation or waiver of any
obligation or duty that may not by law be limited or waived.

     7.   REPRESENTATIONS OF SUB-ADVISER. The Sub-Adviser represents, warrants
and agrees as follows:

     (a)  The Sub-Adviser (i) is registered as an investment adviser under the
Advisers Act and will continue to be so registered for so long as this Agreement
remains in effect; (ii) is not prohibited by the 1940 Act or the Advisers Act
from performing the services contemplated by this Agreement; (iii) has met, and
will seek to continue to meet for so long as this Agreement remains in effect,
any other applicable federal or state requirements, or the applicable
requirements of any regulatory or industry self-regulatory agency, necessary to
be met in order to perform the services contemplated by this Agreement; (iv) has
the authority to enter into and perform the services contemplated by this
Agreement; and (v) will promptly notify UBS Global AM of the occurrence of any
event that would disqualify the Sub-Adviser from serving as an investment
adviser of an investment company pursuant to Section 9(a) of the 1940 Act or
otherwise.

     (b)  The Sub-Adviser has adopted a written code of ethics complying with
the requirements of Rule 17j-1 under the 1940 Act and will provide UBS Global AM
and the Board with a copy of such code of ethics, together with evidence of its
adoption. Within fifteen days of the end of the last calendar quarter of each
year that this Agreement is in effect, a duly authorized officer of the
Sub-Adviser shall certify to UBS Global AM that the Sub-Adviser has complied
with the requirements of Rule 17j-1 during the previous year and that there has
been no material violation of the Sub-Adviser's code of ethics or, if such a
violation has occurred, that appropriate action was taken in response to such
violation. Upon the written request of UBS Global AM, the Sub-Adviser shall
permit UBS Global AM, its employees or its agents to examine the reports
required to be made by the Sub-Adviser pursuant to Rule 17j-1 and all other
records relevant to the Sub-Adviser's code of ethics.

     (c)  The Sub-Adviser has provided UBS Global AM with a copy of its Form
ADV, as most recently filed with the Securities and Exchange Commission ("SEC"),
and promptly will furnish a copy of all amendments to UBS Global AM at least
annually.

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     (d)  The Sub-Adviser will notify UBS Global AM of any change of control
of the Sub-Adviser, including any change of its general partners or 25%
shareholders or 25% limited partners, as applicable, and any changes in the
key personnel who are either the portfolio manager(s) of the portfolio or
senior management of the Sub-Adviser, in each case prior to or promptly after
such change.

     8.   REPRESENTATIONS OF UBS GLOBAL AM. UBS GLOBAL AM represents, warrants
and agrees that UBS GLOBAL AM (i) is registered as an investment adviser under
the Advisers Act and will continue to be so registered for so long as this
Agreement remains in effect; (ii) is not prohibited by the 1940 Act or the
Advisers Act from performing the services contemplated by the Management
Agreement; (iii) has met, and will seek to continue to meet for so long as this
Agreement remains in effect, any other applicable federal or state requirements,
or the applicable requirements of any regulatory or industry self-regulatory
agency, necessary to be met in order to perform the services contemplated by the
Management Agreement; (iv) has the authority to enter into and perform the
services contemplated by the Management Agreement and the execution, delivery
and performance by UBS GLOBAL AM of the Management Agreement does not contravene
or constitute a default under any agreement binding upon UBS GLOBAL AM; (v) has
the authority to enter into this Agreement and appoint the Sub-Adviser as an
investment sub-adviser to perform the services contemplated by this Agreement;
(vi) will promptly notify the Sub-Adviser of the occurrence of any event that
would disqualify UBS GLOBAL AM from serving as an investment adviser of an
investment company pursuant to Section 9(a) of the 1940 Act or otherwise.

     9.   SURVIVAL OF REPRESENTATIONS AND WARRANTIES; DUTY TO UPDATE
INFORMATION. All representations and warranties made by the Sub-Adviser and UBS
GLOBAL AM pursuant to Sections 7 and 8, respectively, shall survive for the
duration of this Agreement and the parties hereto shall promptly notify each
other in writing upon becoming aware that any of the foregoing representations
and warranties are no longer true.

     10.  SERVICES NOT EXCLUSIVE. The services furnished by the Sub-Adviser
hereunder are not to be deemed exclusive, and except as the Sub-Adviser may
otherwise agree in writing, the Sub-Adviser shall be free to furnish similar
services to others so long as its services under this Agreement are not impaired
thereby. Nothing in this Agreement shall limit or restrict the right of any
director, officer or employee of the Sub-Adviser, who may also be a trustee,
officer or employee of the Trust, to engage in any other business or to devote
his or her time and attention in part to the management or other aspects of any
other business, whether of a similar nature or a dissimilar nature.

     11.  DURATION AND TERMINATION.

     (a)  This Agreement shall become effective upon the date first above
written, provided that this Agreement shall not take effect unless (i) it has
first been approved (A) by a vote of a majority of those trustees of the Trust
who are not parties to this Agreement or interested persons of any such party
("Independent Trustees"), cast in person at a meeting called for the purpose of
voting on such approval and (B) by vote of a majority of the Portfolio's
outstanding voting securities, unless UBS Global AM has authority to enter into
this Agreement pursuant to exemptive relief from the SEC without a vote of the
Portfolio's outstanding voting securities, and (ii) the Sub-Adviser has received
written notice from UBS Global AM that the Sub-Adviser may commence placing

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purchase and sell orders for investments and other related transactions for the
Portfolio or Segment.

     (b)  Unless sooner terminated as provided herein, this Agreement shall
continue in effect for two years from its effective date. Thereafter, if not
terminated, this Agreement shall continue automatically for successive periods
of twelve months each, provided that such continuance is specifically approved
at least annually in conformity with the requirements of the 1940Act (i) by a
vote of a majority of the Independent Trustees, cast in person at a meeting
called for the purpose of voting on such approval, and (ii) by the Board or by
vote of a majority of the outstanding voting securities of the Portfolio.

     (c)  Notwithstanding the foregoing, this Agreement may be terminated at any
time, without the payment of any penalty, by vote of the Board or by a vote of a
majority of the outstanding voting securities of the Portfolio on 60 days'
written notice to the Sub-Adviser. This Agreement may also be terminated,
without the payment of any penalty, by UBS Global AM: (i) upon 120 days' written
notice to the Sub-Adviser; (ii) upon material breach by the Sub-Adviser of any
of the representations, warranties and agreements set forth in Paragraph 7 of
this Agreement; or (iii) immediately if, in the reasonable judgment of UBS
Global AM, the Sub-Adviser becomes unable to discharge its duties and
obligations under this Agreement, including circumstances such as financial
insolvency of the Sub-Adviser or other circumstances that could adversely affect
the Portfolio. This Agreement may also be terminated, without the payment of any
penalty, by the Sub-Adviser: (i) upon 120 days' written notice to UBS Global AM;
(ii) upon material breach by UBS Global AM of any of the representations,
warranties and agreements set forth in Paragraph 8 of this Agreement provided
that UBS Global AM will be given a reasonable period not less than 60 days to
cure such material breach; or (iii) upon 60 days written notice if, in the
reasonable judgment of the Sub-Adviser, UBS Global AM becomes unable to
discharge its duties and obligations under this Agreement, including
circumstances such as financial insolvency of UBS Global AM or other
circumstances that could adversely affect the Portfolio, provided that UBS
Global AM will be given the opportunity to demonstrate its ability to discharge
such duties and obligations under this Agreement. This Agreement will terminate
automatically in the event of its assignment or upon termination of the
Management Agreement, as it relates to this Portfolio.

     12.  AMENDMENT OF THIS AGREEMENT. No provision of this Agreement may be
changed, waived, discharged or terminated orally, but only by an instrument in
writing signed by the party against whom enforcement of the change, waiver,
discharge or termination is sought. To the extent required by applicable law, no
amendment of this Agreement shall be effective until approved (i) by a vote of a
majority of the Independent Trustees, and (ii) if the terms of this Agreement
shall have changed, by a vote of a majority of the Portfolio's outstanding
voting securities (except in the case of (ii), pursuant to the terms and
conditions of the SEC order permitting it to modify the Agreement without such
vote).

     13.  GOVERNING LAW. This Agreement shall be construed in accordance with
the 1940 Act and the laws of the State of New York, without giving effect to the
conflicts of laws principles thereof. To the extent that the applicable laws of
the State of New York conflict with the applicable provisions of the 1940 Act,
the latter shall control.

     14.  MISCELLANEOUS. The captions in this Agreement are included for
convenience of reference only and in no way define or delimit any of the
provisions hereof or otherwise affect their

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construction or effect. If any provision of this Agreement shall be held or made
invalid by a court decision, statute, rule or otherwise, the remainder of this
Agreement shall not be affected thereby. This Agreement shall be binding upon
and shall inure to the benefit of the parties hereto and their respective
successors. As used in this Agreement, the terms "majority of the outstanding
voting securities," "affiliated person," "interested person," "assignment,"
"broker," "investment adviser," "net assets," "sale," "sell" and "security"
shall have the same meanings as such terms have in the 1940 Act, subject to such
exemption as may be granted by the SEC by any rule, regulation or order. Where
the effect of a requirement of the federal securities laws reflected in any
provision of this Agreement is made less restrictive by a rule, regulation or
order of the SEC, whether of special or general application, such provision
shall be deemed to incorporate the effect of such rule, regulation or order.
This Agreement may be signed in counterpart.

     15.  NOTICES. Any notice herein required is to be in writing and is deemed
to have been given to the Sub-Adviser or UBS Global AM upon receipt of the same
at their respective addresses set forth below. All written notices required or
permitted to be given under this Agreement will be delivered by personal
service, by postage mail return receipt requested or by facsimile machine or a
similar means of same delivery which provides evidence of receipt (with a
confirming copy by mail as set forth herein). All notices provided to UBS Global
AM will be sent to the attention of Amy Doberman, General Counsel. All notices
provided to the Sub-Adviser will be sent to the attention of Matt Simpson,
General Counsel - Asset Management Services.

     IN WITNESS WHEREOF, the parties hereto have caused this instrument to be
executed by their duly authorized signatories as of the date and year first
above written.


                                       UBS GLOBAL ASSET
                                       MANAGEMENT (US) INC.
                                       51 West 52nd Street
Attest:                                New York, New York 10019-6114

By:  /s/ Todd Lebo                     By:  /s/ Amy R. Doberman
     -------------------------              ------------------------------
     Name:  Todd Lebo                       Name:  Amy R. Doberman
     Title: Director                        Title: Managing Director

                                       GE ASSET MANAGEMENT
                                       INCORPORATED

Attest:

By:  /s/ Margarette Shim               By:  /s/ Matthew J. Simpson
     -------------------------              ------------------------------
     Name:  Margarette Shim                 Name:  Matthew J. Simpson
     Title: Vice President                  Title: SVP & Gen. Counsel -
                                                    Asset Mgmt Svces



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