<PAGE>

                                                                   Exhibit 10.27

                         INVESTMENT MANAGEMENT AGREEMENT

AGREEMENT made this 3rd day of November, 2003, by and between NUVEEN MUNICIPAL
HIGH INCOME OPPORTUNITY FUND, a Massachusetts business trust (the "Fund"), and
NUVEEN ADVISORY CORP., a Delaware corporation (the "Adviser").

                               W I T N E S S E T H

In consideration of the mutual covenants hereinafter contained, it is hereby
agreed by and between the parties hereto as follows:

1.       The Fund hereby employs the Adviser to act as the investment adviser
for, and to manage the investment and reinvestment of the assets of the Fund in
accordance with the Fund's investment objective and policies and limitations,
and to administer the Fund's affairs to the extent requested by and subject to
the supervision of the Board of Trustees of the Fund for the period and upon the
terms herein set forth. The investment of the Fund's assets shall be subject to
the Fund's policies, restrictions and limitations with respect to securities
investments as set forth in the Fund's then current registration statement under
the Investment Company Act of l940, and all applicable laws and the regulations
of the Securities and Exchange Commission relating to the management of
registered closed-end management investment companies.

The Adviser accepts such employment and agrees during such period to render such
services, to furnish office facilities and equipment and clerical, bookkeeping
and administrative services

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                                        2

(other than such services, if any, provided by the Fund's transfer agent) for
the Fund, to permit any of its officers or employees to serve without
compensation as trustees or officers of the Fund if elected to such positions,
and to assume the obligations herein set forth for the compensation herein
provided. The Adviser shall, for all purposes herein provided, be deemed to be
an independent contractor and, unless otherwise expressly provided or
authorized, shall have no authority to act for nor represent the Fund in any
way, nor otherwise be deemed an agent of the Fund.

2.       For the services and facilities described in Section l, the
Fund will pay to the Adviser, at the end of each calendar month, an investment
management fee computed by applying the following annual rate to the average
daily net assets of the Fund:

<TABLE>
<CAPTION>
 RATE                     AVERAGE DAILY NET ASSETS(1)
 ----                     ---------------------------
<S>                       <C>
..7500%                    Up to $125 million
..7375%                    $125 to $250 million
..7250%                    $250 to $500 million
..7125%                    $500 million to $1 billion
..7000%                    $1 billion to $2 billion
..6750%                    $2 billion and over
</TABLE>

(1)Including net assets attributable to MuniPreferred Shares.

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 shall have been in effect during the month and year, respectively.
The services of the Adviser to the Fund under this Agreement are not to be
deemed exclusive, and the Adviser shall be free to render similar services or
other services to others so long as its services hereunder are not impaired
thereby.

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                                       3

3.       The Adviser shall arrange for officers or employees of the Adviser to
serve, without compensation from the Fund, as trustees, officers or agents of
the Fund, if duly elected or appointed to such positions, and subject to their
individual consent and to any limitations imposed by law.

4.       Subject to applicable statutes and regulations, it is understood that
officers, trustees, or agents of the Fund are, or may be, interested in the
Adviser as officers, directors, agents, shareholders or otherwise, and that the
officers, directors, shareholders and agents of the Adviser may be interested in
the Fund otherwise than as trustees, officers or agents.

5.       The Adviser shall not be liable for any loss sustained by reason of the
purchase, sale or retention of any security, whether or not such purchase, sale
or retention shall have been based upon the investigation and research made by
any other individual, firm or corporation, if such recommendation shall have
been selected with due care and in good faith, except loss resulting from
willful misfeasance, bad faith, or gross negligence on the part of the Adviser
in the performance of its obligations and duties, or by reason of its reckless
disregard of its obligations and duties under this Agreement.

6.       The Adviser currently manages other investment accounts and funds,
including those with investment objectives similar to the Fund, and reserves the
right to manage other such accounts and funds in the future. Securities
considered as investments for the Fund may also be appropriate for other
investment accounts and funds that may be managed by the Adviser. Subject to
applicable laws and regulations, the Adviser will attempt to allocate equitably
portfolio transactions among the portfolios of its other investment accounts and
funds purchasing securities whenever decisions are

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                                       4

made to purchase or sell securities by the Fund and one or more of such other
accounts or funds simultaneously. In making such allocations, the main factors
to be considered by the Adviser will be the respective investment objectives of
the Fund and such other accounts and funds, the relative size of portfolio
holdings of the same or comparable securities, the availability of cash for
investment by the Fund and such other accounts and funds, the size of investment
commitments generally held by the Fund and such accounts and funds, and the
opinions of the persons responsible for recommending investments to the Fund and
such other accounts and funds.

7.       This Agreement shall continue in effect until July l, 2005, unless and
until terminated by either party as hereinafter provided, and shall continue in
force from year to year thereafter, but only as long as such continuance is
specifically approved, at least annually, in the manner required by the
Investment Company Act of l940.

         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 Fund or by the Adviser upon sixty (60) days' written notice to the other
party. The Fund may effect termination by action of the Board of Trustees or by
vote of a majority of the outstanding voting securities of the Fund, accompanied
by appropriate notice.

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                                       5

         This Agreement may be terminated, at any time, without the payment of
any penalty, by the Board of Trustees of the Fund, 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 Adviser, or any
officer or director of the Adviser, has taken any action which results in a
breach of the covenants of the Adviser set forth herein.

         Termination of this Agreement shall not affect the right of the Adviser
to receive payments on any unpaid balance of the compensation, described in
Section 2, earned prior to such termination.

8.       If any provision of this Agreement shall be held or made invalid by a
court decision, statute, rule, or otherwise, the remainder shall not be thereby
affected.

9.       Any notice under this Agreement shall be in writing, addressed and
delivered or mailed, postage prepaid, to the other party at such address as such
other party may designate for receipt of such notice.

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                                       6

10.      The Fund's Declaration of Trust is on file with the Secretary of the
Commonwealth of Massachusetts. This Agreement is executed on behalf of the Fund
by the Fund's officers as officers and not individually and the obligations
imposed upon the Fund by this Agreement are not binding upon any of the Fund's
Trustees, officers or shareholders individually but are binding only upon the
assets and property of the Fund.

         IN WITNESS WHEREOF, the Fund and the Adviser have caused this Agreement
to be executed on the day and year above written.

                                    NUVEEN MUNICIPAL HIGH INCOME
                                    OPPORTUNITY FUND

                                    by: /s/ Jessica R. Droeger
                                       -------------------------------
                                               Vice President

Attest:  /s/ Virginia O'Neal
         ---------------------------
         Assistant Secretary

                                              NUVEEN ADVISORY CORP.

                                              By: /s/ William M. Fitzgerald
                                              ----------------------------------
                                                      Managing Director

Attest: /s/ Stuart Cohen
        --------------------------------
        Assistant Secretary
<PAGE>

                                                                  Exhibit  10.27

                         EXPENSE REIMBURSEMENT AGREEMENT

AGREEMENT made this 3rd day of November, 2003, by and between NUVEEN MUNICIPAL
HIGH INCOME OPPORTUNITY FUND, a Massachusetts business trust (the "Fund"), and
NUVEEN ADVISORY CORP., a Delaware corporation (the "Adviser").

                               W I T N E S S E T H

WHEREAS, the Fund and the Adviser have separately entered into an Investment
Management Agreement of even date herewith (the "Management Agreement");

In consideration of the mutual covenants hereinafter contained, and in
connection with the establishment and commencement of operations of the Fund, it
is hereby agreed by and between the parties hereto as follows:

1.       For the period from the commencement of the Fund's operations through
November 30, 2003 and for the 12 month periods ending November 30 in each
indicated year during the term of the Management Agreement (including any
continuation done in accordance with Section 15(c) of the Investment Company Act
of 1940), the Adviser agrees to reimburse expenses (including the management fee
and other expenses) in the amounts determined by applying the following annual
rates to the average daily net assets of the Fund:

<PAGE>


<TABLE>
<CAPTION>
    Period Ending         Percentage Reimbursed (as a                            Percentage Reimbursed (as
      November            percentage of average daily       Period Ending         a percentage of average
          30                     net assets)(1)              November 30           daily net assets)(1)

<S>                       <C>                               <C>                  <C>
         2003(2)                    .32%
         2004                       .32%                      2008                      .32%
         2005                       .32%                      2009                      .24%
         2006                       .32%                      2010                      .16%
         2007                       .32%                      2011                      .08%
</TABLE>

(1) Including net assets attributable to MuniPreferred Shares.

(2) From the of operations.

2.       To effect the expense reimbursement provided for in this Agreement, the
Fund may offset the appropriate amount of the reimbursement contemplated
hereunder against the management fee payable under the Management Agreement.

3.       This Agreement, and the Adviser's obligation to so reimburse expenses
hereunder, shall terminate on the earlier of (a) November 30, 2011 or (b)
termination of the Management Agreement.

4.       Except as provided in paragraph 3, above, this Agreement may be
terminated only by the vote of (a) the Board of Trustees of the Fund, including
the vote of the members of the Board who are not "interested persons" within the
meaning of the Investment Company Act of 1940, and (b) a majority of the
outstanding voting securities of the Fund.

5.       If any provision of this Agreement shall be held or made invalid by a
court decision, statute, rule, or otherwise, the remainder shall not be thereby
affected.

                                       2

<PAGE>

6.       The Fund's Declaration of Trust is on file with the Secretary of the
Commonwealth of Massachusetts. This Agreement is executed on behalf of the Fund
by the Fund's officers as officers and not individually and the obligations
imposed upon the Fund by this Agreement are not binding upon any of the Fund's
Trustees, officers or shareholders individually but are binding only upon the
assets and property of the Fund.

         IN WITNESS WHEREOF, the Fund and the Adviser have caused this Agreement
to be executed on the day and year above written.

                                               NUVEEN MUNICIPAL HIGH INCOME
                                               OPPORTUNITY FUND

                                               by:      /s/ Jessica R. Droeger
                                                        ------------------------
                                                             Vice President

Attest:  /s/ Virginia O'Neal
         ----------------------------
          Assistant Secretary

                                               NUVEEN ADVISORY CORP.

                                               by:  /s/ William M. Fitzgerald
                                                    ---------------------------
                                                             Managing Director

Attest:  /s/ Stuart Cohen
         --------------------------
         Assistant Secretary

                                       3