Document:

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                                                                    EXHIBIT 10.3

                        INVESTMENT SUB-ADVISORY AGREEMENT

         AGREEMENT made as of this 14th day of March, 2003 by and between Nuveen
Institutional Advisory Corp., a Delaware corporation and a registered investment
adviser ("Manager"), and Froley, Revy Investment Co., Inc., a California
corporation and a federally registered investment adviser ("Sub-Adviser").

         WHEREAS, Manager serves as the investment manager for the Nuveen
Preferred and Convertible 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 a certain designated portion of the Fund's
investment portfolio, 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 appointment 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 portion of the Fund's investment
portfolio allocated to the Sub-Adviser, all on behalf of the Fund and as
described in the investment policy section of the Fund's initial registration
statement on Form N-2 as declared effective by the Securities and Exchange
Commission, as such policies described therein may subsequently be changed by
the Fund's Board of Trustees and publicly described. In the performance of its
duties, Sub-Adviser will satisfy its fiduciary duties to the Fund, will monitor
the Fund's investments in convertible securities (and other assets in which the
Sub-Adviser is authorized to invest), 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.

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         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. 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 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 that 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 with
                  respect to convertible securities (and other assets in which
                  the Sub-Adviser is authorized to invest), the performance of
                  the Fund's investment portfolio allocated to the Sub-Adviser
                  in relation to relevant 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

                                       2

<PAGE>

         (d)      will prepare such books and records with respect to the Fund's
                  securities transactions for the Fund's investment portfolio
                  allocated to the Sub-Adviser 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.

         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 40.0% of the investment management fee payable by the
Fund to the Manager with respect to the Sub-Adviser's allocation of Fund net
assets (including net assets attributable to FundPreferred Shares and the
principal amount of borrowings pursuant to the Management Agreement) up to the
first $500,000,000 of the average daily Fund net assets allocated to the
Sub-Adviser and 35.0% of the average daily Fund net assets over $500,000,000
allocated to the Sub-Adviser, as the net amount of such fee payable by the Fund
to the Manager is reduced by the obligation of Manager to reimburse certain fees
and expenses to the Fund pursuant to an Expense Reimbursement Agreement dated
February 20, 2003 by and between the Fund and the Manager, as such agreement may
be modified from time to time.

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 allocated to
the Sub-Adviser, 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

                                       3

<PAGE>

by Sub-Adviser to be equitable to each. Manager recognizes, and has advised
Fund's Board of 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.
The federal securities laws impose liabilities under certain circumstances on
persons who act in good faith, and therefore nothing in this Agreement shall
waive or limit any rights which the Fund may have under those laws.

         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, 2004 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,
2004 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.

                                       4

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         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 court of competent jurisdiction that
the Sub-Adviser or any officer or director of the Sub-Adviser has taken any
action that 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 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

<TABLE>
<S>                                         <C>
If to the Manager:                          If to the Sub-Adviser:

Nuveen Institutional Advisory Corp.         Froley, Revy Investment Co., Inc.
333 West Wacker Drive                       10900 Wilshire Boulevard
Chicago, Illinois 60606                     Los Angeles, California 90024
Attention: John P. Amboian                  Attention: Andrea Revy O'Connell

With a copy to:                             With a copy to:

Nuveen Investments, Inc.
333 West Wacker Drive
Chicago, Illinois 60606
Attention: General Counsel
</TABLE>

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

                                       5

<PAGE>

         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              FROLEY, REVY INVESTMENT CO.,
CORP., a Delaware corporation              INC., a California corporation

By: s/ Gifford R. Zimmerman                By: /s/ K. Andrea O'Connell
    ------------------------                   -------------------------
Title: Managing Director                   Title: President and C.E.O

                                       6<PAGE>

                                                                    EXHIBIT 10.4

                            NUVEEN INVESTMENTS, INC.
                              333 WEST WACKER DRIVE
                             CHICAGO, ILLINOIS 60606

                                February 1, 2003

Barra, Inc.
2100 Milvia Street
Berkeley, California 94704
Attention: Kamal Duggirala

Maestro, LLC
555 California Street, Suite 2975
San Francisco, California 94104
Attention: Neil L. Rudolph

The Individuals Listed on the
Signature Pages Hereto
555 California Street, Suite 2975
San Francisco, California 94104

Gentlemen:

         We refer to the Acquisition Agreement by and among Barra, Inc.
("Barra"), Symphony Asset Management, Inc. ("SAMI," which has been subsequently
liquidated into Barra), Maestro, LLC ("Maestro" and, together with SAMI, the
"Members" and each a "Member"), Praveen K. Gottipalli, Michael J. Henman, Neil
L. Rudolph and Jeffrey L. Skelton (collectively, the "Company Principals"),
Symphony Asset Management LLC (the "Company" and, together with Barra, the
Members and the Company Principals, the "Symphony Parties" and each a "Symphony
Party") and Nuveen Investments, Inc. (formerly known as The John Nuveen Company)
("Buyer"), dated as of June 15, 2001, as amended (the "Acquisition Agreement"),
pursuant to which Buyer acquired all of the Membership Interests (as defined in
the Acquisition Agreement) of the Company on the terms and subject to the
conditions set forth therein. Capitalized terms used but not defined in this
letter agreement have the meanings given to such terms in the Acquisition
Agreement. This letter agreement amends the Acquisition Agreement as set forth
herein. Except as set forth herein, all of the terms and conditions of the
Acquisition Agreement shall remain in effect without modification and shall be
deemed to apply to this letter agreement, including without limitation those
provisions set forth in Article X thereof. The parties agree, in consideration
of the covenants and agreements set forth herein, and intending to be legally
bound, as follows:

<PAGE>

Barra, Inc., Maestro, LLC, et al.
February 1, 2003
Page 2

         1.       In clause (d) of Exhibit R to the Acquisition Agreement, the
number "$130 million" (appearing twice) is hereby amended to read "$120
million."

         2.       Exhibit R to the Acquisition Agreement is hereby amended to
add thereto the following paragraph (i):

         "(i) (A) The contingent purchase price consideration to be paid
         pursuant to Section 1.5 of the Acquisition Agreement shall include a
         quarterly Contingent New Asset Payment as described below. Any
         Contingent New Asset Payments shall be paid by Buyer solely to Maestro,
         and shall be paid within the forth-five (45) calendar days following
         the end of the fiscal quarter to which the Contingent New Asset Payment
         relates; provided that if Maestro disputes the Fee Accounting (as
         defined below) pursuant to the terms of sub-paragraph (C) below, the
         Contingent New Asset Payment shall instead be paid within five Business
         Days of the resolution of such dispute pursuant to the terms of
         sub-paragraph (C) below. Payments of the Contingent New Asset Payment
         shall be made by Buyer in cash to the account designated in Wire
         Transfer instructions provided to Buyer by Maestro not less than two
         Business Days prior to the date on which the applicable Contingent New
         Asset Payment is due.

         (B) Contingent New Asset Payment shall mean an amount equal to the sum
         of:

(1)      the product of (x) 0.004 and (y) the New Hedged Assets for the
applicable fiscal quarter (or such shorter period as provided below); plus

(2)      the product of (x) 0.002 and (y) the New Traditional Client Assets for
the applicable fiscal quarter (or such shorter period as provided below); plus

(3)      the product of (x) 0.001 and (y) the New Other Assets for the
applicable fiscal quarter (or such shorter period as provided below).

Notwithstanding the foregoing, in no event shall the aggregate of all Contingent
New Asset Payments exceed $3.0 million. The applicable fiscal quarter shall
initially mean the period from February 1, 2003 through June 30, 2003, and shall
thereafter mean each subsequent fiscal quarter beginning with the quarter
commencing July 1, 2003 and ending September 30, 2003; provided, that the final
fiscal quarter shall be the fiscal quarter ending September 30, 2006 and
thereafter the right of Maestro to receive Contingent New Asset Payments shall
terminate except with respect to any unpaid amount relating to a period ending
on or before September 30, 2006. As used herein, the following terms shall have
the following meanings:

"New Hedged Assets" shall mean the dollar amount of the gross new client assets
invested in funds (whether or not registered pursuant to the Investment Company
Act) or separate accounts managed or sub-advised by the Company for which the
Company is

<PAGE>

Barra, Inc., Maestro, LLC, et al.
February 1, 2003
Page 3

contracted to be paid a fee that is based on both assets under management and
the investment performance of the fund or account.

"New Traditional Client Assets" shall mean the dollar amount of the gross new
client assets invested in funds or separate accounts managed or sub-advised by
the Company which do not come within the definition of New Hedged Assets (e.g.,
a long-only account paying an asset based fee) and which are raised through
existing clients and prospects of the Company.

"New Other Assets" shall mean the dollar amount of the gross new client assets
invested in funds or separate accounts managed or sub-advised by the Company
which do not come within the definition of New Hedged Assets or New Traditional
Client Assets (e.g., a long-only account paying an asset based fee raised
through Nuveen distribution channels).

Notwithstanding anything to the contrary set forth herein, new client assets
managed or sub-advised by Symphony which pay fees that are nominal or were not
negotiated on an arms' length basis shall not be included as New Hedged Assets,
New Traditional Client Assets or New Other Assets for purposes of calculating
the Contingent New Asset Payments.

         (C) Buyer shall prepare and deliver not later than the thirtieth (30th)
calendar day following the end of the applicable fiscal quarter a statement
setting forth the New Hedged Assets, New Traditional Client Assets and New Other
Assets (collectively, the "New Assets") for the applicable period (the "New
Assets Accounting"), which New Assets Accounting shall set forth in reasonable
detail the calculation of such New Assets and shall be made in a manner
consistent in all respects with the foregoing terms of this letter agreement.
Following receipt by Maestro of the New Assets Accounting, solely for the
purpose of reviewing such New Assets Accounting as it relates to the applicable
Contingent New Assets Payment, Buyer shall provide Maestro access, during normal
business hours at the request of Maestro, to the books and records of Buyer and
its Subsidiaries and to their personnel and accountants to the extent reasonably
necessary to review the accuracy of the applicable New Asset Accounting;
provided, however, that such access shall be conducted in a manner that does not
unreasonably interfere with the operation of the business of Buyer and its
Subsidiaries. Within fifteen (15) calendar days after delivery to Maestro of the
Fee Accounting, Maestro may dispute all or a portion of such Fee Accounting by
giving written notice (a "New Asset Dispute Notice") to Buyer of such dispute
setting forth in reasonable detail the basis for such dispute (any such dispute,
a "New Asset Dispute"). If Maestro does not dispute the Fee Accounting during
such 15 day period, the Fee Accounting shall be final and binding upon the
parties. If Maestro shall deliver a New Asset Dispute Notice during such 15 day
period, Maestro and Buyer shall promptly commence good faith negotiations with a
view to resolving such dispute, and any resolution of such dispute shall be
reflected in a written agreement signed by both such parties. If Maestro and
Buyer are unable to resolve such dispute within thirty (30) calendar days
following deliver of such New Asset Dispute Notice,

<PAGE>

Barra, Inc., Maestro, LLC, et al.
February 1, 2003
Page 4

such dispute shall thereafter be referred to an Independent Accounting Firm for
a resolution of such Dispute in accordance with the terms of this paragraph (i);
provided, that any Dispute relating to the interpretation of this Agreement that
is not resolved by the parties after good faith negotiations shall be resolved
pursuant to the arbitration process described in Section 9.8 of the Acquisition
Agreement. The determinations of the Independent Accounting Firm with respect to
any New Asset Dispute shall be rendered within thirty (30) calendar days after
referral to such firm or as soon thereafter as reasonably practicable, shall be
final and binding upon the parties, and the amount so determined shall be used
to calculate and pay the Contingent New Asset Payment. Maestro and Buyer agree
that the procedures set forth in this paragraph (i) or incorporated herein shall
be the sole and exclusive remedy with respect to the determination of the amount
of any Contingent New Asset Payment. All of the fees and expenses of any
Independent Accounting Firm retained pursuant to the foregoing shall be paid 50%
by Buyer and 50% by Maestro."

         Please acknowledge your understanding of our agreement as set forth
herein by signing this letter in the space provided on the next page and
returning a copy to the undersigned. Upon execution and delivery by all of the
parties set forth below, the Acquisition Agreement shall be deemed amended to
the extent set forth in this letter.

                                                 Very truly yours,

                                                 NUVEEN INVESTMENTS, INC.

                                                 By: /s/ Alan G. Berkshire
                                                     --------------------------
                                                 Name: Alan G. Berkshire
                                                 Title: Senior Vice President

Accepted and agreed to as of
the 1st day of February, 2003:

BARRA, INC.

By: /s/ Greg Stockett
    -------------------------------
Name: Greg Stockett
Title: Chief Financial Officer

MAESTRO, LLC

By: /s/ Neil L. Rudolph
    -------------------------------
Name: Neil L. Rudolph
Title: Member

/s/ Praveen K. Gottipalli
---------------------------
PRAVEEN K. GOTTIPALLI

<PAGE>

Barra, Inc., Maestro, LLC, et al.
February 1, 2003
Page 5

/s/ Michael J. Henman
------------------------------------
MICHAEL J. HENMAN

/s/ Neil L. Rudolph
------------------------------------
NEIL L. RUDOLPH

/s/ Jeffrey L. Skelton
------------------------------------
JEFFREY L. SKELTON

SYMPHONY ASSET MANAGEMENT LLC

By: Nuveen Investments, Inc., its Managing Member

By: /s/ Alan G. Berkshire
    ----------------------
Name: Alan G. Berkshire
Title: Senior Vice President

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