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                                                                 EXHIBIT 10.3(a)

                        INVESTMENT SUB-ADVISORY AGREEMENT

     AGREEMENT made as of this 1st day of June, 2002 by and between Nuveen
Institutional Advisory Corp., a Delaware corporation and a registered investment
adviser ("Manager"), and Spectrum Asset Management Inc., a Connecticut
corporation and a federally registered investment adviser ("Sub-Adviser").

     WHEREAS, Manager serves as the investment manager for the Nuveen Quality
Preferred Income Fund (the "Fund"), a closed-end management investment company
registered under the Investment Company Act of 1940, as amended (the "1940 Act")
pursuant to an Investment Management Agreement between Manager and the Fund (as
such agreement may be modified from time to time, the "Management Agreement");
and

     WHEREAS, Manager desires to retain Sub-Adviser as its agent to furnish
investment advisory services for the Fund, upon the terms and conditions
hereafter set forth;

     NOW, THEREFORE, in consideration of the mutual covenants herein contained,
the parties hereto agree as follows:

     1. Appointment. Manager hereby appoints Sub-Adviser to provide certain
sub-investment advisory services to the Fund for the period and on the terms set
forth in this Agreement. Sub-Adviser accepts such appointments and agrees to
furnish the services herein set forth for the compensation herein provided.

     2. Services to be Performed. Subject always to the supervision of Fund's
Board of Trustees and the Manager, Sub-Adviser will furnish an investment
program in respect of, make investment decisions for, and place all orders for
the purchase and sale of securities for the Fund, all on behalf of the Fund. In
the performance of its duties, Sub-Adviser will satisfy its fiduciary duties to
the Fund, will monitor the Fund's investments, and will comply with the
provisions of the Fund's Declaration of Trust and By-laws, as amended from time
to time, and the stated investment objectives, policies and restrictions of the
Fund. Manager will provide Sub-Adviser with current copies of the Fund's
Declaration of Trust, By-laws, prospectus and any amendments thereto, and any
objectives, policies or limitations not appearing therein as they may be
relevant to Sub-Adviser's performance under this Agreement. Sub-Adviser and
Manager will each make its officers and employees available to the other from
time to time at reasonable times to review investment policies of the Fund and
to consult with each other regarding the investment affairs of the Fund.
Sub-Adviser will report to the Board of Trustees and to Manager with respect to
the implementation of such program.

     Sub-Adviser is authorized to select the brokers or dealers that will
execute the purchases and sales of portfolio securities for the Fund, and is
directed to use its commercially reasonable efforts to obtain best execution,
which includes most favorable net results and execution of the Fund's orders,
taking into account all appropriate factors, including price, dealer spread or
commission, size and difficulty of the transaction and research or other
services provided. Sub-


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Adviser may select itself as a broker, in an agency capacity, to execute
transactions in portfolio securities for the Fund in accordance with policies
and procedures adopted by the Board of Trustees from time to time. It is
understood that the Sub-Adviser will not be deemed to have acted unlawfully, or
to have breached a fiduciary duty to the Fund, or be in breach of any obligation
owing to the Fund under this Agreement, or otherwise, solely by reason of its
having caused the Fund to pay a member of a securities exchange, a broker or a
dealer (including the Sub-Adviser's internal broker-dealer) a commission for
effecting a securities transaction for the Fund in excess of the amount of
commission another member of an exchange, broker or dealer would have charged if
the Sub-Adviser determined in good faith that the commission paid was reasonable
in relation to the brokerage or research services provided by such member,
broker or dealer, viewed in terms of that particular transaction or the
Sub-Adviser's overall responsibilities with respect to its accounts, including
the Fund, as to which it exercises investment discretion. In addition, if in the
judgment of the Sub-Adviser, the Fund would be benefited by supplemental
services, the Sub-Adviser is authorized to pay spreads or commissions to brokers
or dealers furnishing such services in excess of spreads or commissions which
another broker or dealer may charge for the same transaction, provided that the
Sub-Adviser determined in good faith that the commission or spread paid was
reasonable in relation to the services provided. The Sub-Adviser will properly
communicate to the officers and trustees of the Fund such information relating
to transactions for the Fund as they may reasonably request. In no instance will
portfolio securities be purchased from or sold to the Manager, Sub-Adviser or
any affiliated person of either the Fund, Manager, or Sub-Adviser, except as may
be permitted under the 1940 Act;

     Sub-Adviser further agrees that it:

     (a)  will use the same degree of skill and care in providing such services
          as it uses in providing services to fiduciary accounts for which it
          has investment responsibilities;

     (b)  will conform to all applicable Rules and Regulations of the Securities
          and Exchange Commission in all material respects and in addition will
          conduct its activities under this Agreement in accordance with any
          applicable regulations of any governmental authority pertaining to its
          investment advisory activities;

     (c)  will report regularly to Manager and to the Board of Trustees of the
          Fund and will make appropriate persons available for the purpose of
          reviewing with representatives of Manager and the Board of Trustees on
          a regular basis at reasonable times the management of the Fund,
          including, without limitation, review of the general investment
          strategies of the Fund, the performance of the Fund in relation to
          standard industry indices and general conditions affecting the
          marketplace and will provide various other reports from time to time
          as reasonably requested by Manager; and

     (d)  will prepare such books and records with respect to the Fund's
          securities transactions as requested by the Manager and will furnish
          Manager and Fund's Board of Trustees such periodic and special reports
          as the Board or Manager may reasonably request.


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     3. Expenses. During the term of this Agreement, Sub-Adviser will pay all
expenses incurred by it in connection with -------- its activities under this
Agreement other than the cost of securities (including brokerage commission, if
any) purchased for the Fund.

     4. Compensation. For the services provided and the expenses assumed
pursuant to this Agreement, Manager will pay the Sub-Adviser, and the
Sub-Adviser agrees to accept as full compensation therefor, a portfolio
management fee equal to the portion specified below of the investment management
fee payable by the Fund to the Manager based on average daily net assets which
includes net assets attributable to Fund Preferred Shares and the principal
amount of borrowings pursuant to the Management Agreement, as the net amount of
such fee is reduced by the obligation of Manager to reimburse certain fees and
expenses to the Fund pursuant to an Expense Reimbursement Agreement of even date
herewith by and between the Fund and the Manager, as such agreement may be
modified from time to time:

         Daily Net Assets                            Percentage of Net
                                                      Management Fee
         Up to $125 million                                50.0%
         $125 million to $150 million                      47.5%
         $150 million to $175 million                      45.0%
         $175 million to $200 million                      42.5%
         $200 million and over                             40.0%


The portfolio management fee shall accrue on each calendar day, and shall be
payable monthly on the first business day of the next succeeding calendar month.
The daily fee accrual shall be computed by multiplying the fraction of one
divided by the number of days in the calendar year by the applicable annual rate
of fee, and multiplying this product by the net assets of the Fund, determined
in the manner established by the Fund's Board of Trustees, as of the close of
business on the last preceding business day on which the Fund's net asset value
was determined.

For the month and year in which this Agreement becomes effective or terminates,
there shall be an appropriate proration on the basis of the number of days that
the Agreement is in effect during the month and year, respectively.

Manager shall not agree to amend the financial terms of the Expense
Reimbursement Agreement or the Management Agreement to the detriment of the
Sub-Adviser by operation of this Section 4 without the express written consent
of the Sub-Adviser.

     5. Services to Others. Manager understands, and has advised Fund's Board of
Trustees, that Sub-Adviser now acts, or may in the future act, as an investment
adviser to fiduciary and other managed accounts, and as investment adviser or
sub-investment adviser to one or more other investment companies that are not a
series of the Fund, provided that whenever the Fund and one or more other
investment advisory clients of Sub-Adviser have available funds for investment,
investments suitable and appropriate for each will be allocated in a manner
believed by Sub-Adviser to be equitable to each. Manager recognizes, and has
advised Fund's Board of


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Trustees, that in some cases this procedure may adversely affect the size of the
position that the Fund may obtain in a particular security. It is further agreed
that, on occasions when the Sub-Adviser deems the purchase or sale of a security
to be in the best interests of the Fund as well as other accounts, it may, to
the extent permitted by applicable law, but will not be obligated to, aggregate
the securities to be so sold or purchased for the Fund with those to be sold or
purchased for other accounts in order to obtain favorable execution and lower
brokerage commissions. In addition, Manager understands, and has advised Fund's
Board of Trustees, that the persons employed by Sub-Adviser to assist in
Sub-Adviser's duties under this Agreement will not devote their full such
efforts and service to the Fund. It is also agreed that the Sub-Adviser may use
any supplemental research obtained for the benefit of the Fund in providing
investment advice to its other investment advisory accounts or for managing its
own accounts.

     6. Limitation of Liability. The Sub-Adviser shall not be liable for, and
Manager will not take any action against the Sub-Adviser to hold Sub-Adviser
liable for, any error of judgment or mistake of law or for any loss suffered by
the Fund (including, without limitation, by reason of the purchase, sale or
retention of any security) in connection with the performance of the
Sub-Adviser's duties under this Agreement, except for a loss resulting from
willful misfeasance, bad faith or gross negligence on the part of the
Sub-Adviser in the performance of its duties under this Agreement, or by reason
of its reckless disregard of its obligations and duties under this Agreement.

     7. Term; Termination; Amendment. This Agreement shall become effective with
respect to the Fund on the same date as the Management Agreement between the
Fund and the Manager becomes effective, provided that it has been approved by a
vote of a majority of the outstanding voting securities of the Fund in
accordance with the requirements of the 1940 Act, and shall remain in full force
until August 1, 2003 unless sooner terminated as hereinafter provided. This
Agreement shall continue in force from year to year thereafter with respect to
the Fund, but only as long as such continuance is specifically approved for the
Fund at least annually in the manner required by the 1940 Act and the rules and
regulations thereunder; provided, however, that if the continuation of this
Agreement is not approved for the Fund, the Sub-Adviser may continue to serve in
such capacity for the Fund in the manner and to the extent permitted by the 1940
Act and the rules and regulations thereunder.

     This Agreement shall automatically terminate in the event of its assignment
and may be terminated at any time without the payment of any penalty by the
Manager on no less than sixty (60) days' written notice to the Sub-Adviser. This
Agreement may be terminated by the Sub-Adviser after July 31, 2003 without
payment of any penalty on no less than sixty (60) days' prior written notice to
the Manager. This Agreement may also be terminated by the Fund with respect to
the Fund by action of the Board of Trustees or by a vote of a majority of the
outstanding voting securities of such Fund on no less than sixty (60) days'
written notice to the Sub-Adviser by the Fund.

     This Agreement may be terminated with respect to the Fund at any time
without the payment of any penalty by the Manager, the Board of Trustees or by
vote of a majority of the outstanding voting securities of the Fund in the event
that it shall have been established by a


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court of competent jurisdiction that the Sub-Adviser or any officer or director
of the Sub-Adviser has taken any action which results in a breach of the
covenants of the Sub-Adviser set forth herein.

     The terms "assignment" and "vote of a majority of the outstanding voting
securities" shall have the meanings set forth in the 1940 Act and the rules and
regulations thereunder.

     Termination of this Agreement shall not affect the right of the Sub-Adviser
to receive payments on any unpaid balance of the compensation described in
Section 4 earned prior to such termination. This Agreement shall automatically
terminate in the event the Investment Management Agreement between the Manager
and the Fund is terminated, assigned or not renewed.

     8. Notice. Any notice under this Agreement shall be in writing, addressed
and delivered or mailed, postage prepaid, to the other party

     If to the Manager:                  If to the Sub-Adviser:

     Nuveen Institutional Advisory Corp. Spectrum Asset Management Inc.
     333 West Wacker Drive               4 High Ridge Park
     Chicago, Illinois 60606             Stamford, Connecticut 06905
     Attention:  John P. Amboian         Attention:  Mark A. Lieb



     With a copy to:                     With a copy to:

     The John Nuveen Company             Wolf, Block, Schorr and Solis-Cohen LLP
     333 West Wacker Drive               250 Park Avenue,
     Chicago, Illinois 60606             New York, New York 10177
     Attention:  General Counsel         Attention:  Herbert Henryson II

or such address as such party may designate for the receipt of such notice.


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     9. Limitations on Liability. All parties hereto are expressly put on notice
of the Fund's Agreement and Declaration of Trust and all amendments thereto, a
copy of which is on file with the Secretary of the Commonwealth of
Massachusetts, and the limitation of shareholder and trustee liability contained
therein. The obligations of the Fund entered in the name or on behalf thereof by
any of the Trustees, representatives or agents are made not individually but
only in such capacities and are not binding upon any of the Trustees, officers,
or shareholders of the Fund individually but are binding upon only the assets
and property of the Fund, and persons dealing with the Fund must look solely to
the assets of the Fund and those assets belonging to the subject Fund, for the
enforcement of any claims.

     10. 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 construction or effect. If any
provision of this Agreement is held or made invalid by a court decision,
statute, rule or otherwise, the remainder of this Agreement will not be affected
thereby. This Agreement will be binding upon and shall inure to the benefit of
the parties hereto and their respective successors.

     11. Applicable Law. This Agreement shall be construed in accordance with
applicable federal law and (except as to Section 9 hereof which shall be
construed in accordance with the laws of Massachusetts) the laws of the State of
Illinois.



     IN WITNESS WHEREOF, the Manager and the Sub-Adviser have caused this
Agreement to be executed as of the day and year first above written.

NUVEEN INSTITUTIONAL ADVISORY                  SPECTRUM ASSET MANAGEMENT,
CORP., a Delaware corporation                  INC., a Connecticut corporation


By:  /s/ Gifford R. Zimmerman                  By: /s/ Bernard Sussman
    ----------------------------                   --------------------------
Title: Managing Director                       Title: Executive Director
                                                      -----------------------


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