CHANGE OF CONTROL AGREEMENT

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                                                           Exhibit 10

                          CHANGE OF CONTROL AGREEMENT
                          --------------------------

       THIS AGREEMENT, entered into as of the 13th day of March, 2006, by
and between MARSHALL & ILSLEY CORPORATION (the "Company"), and Michael C.
Smith (the "Executive") (hereinafter collectively referred to as "the
parties").

                            W I T N E S S E T H :

       WHEREAS, the Board of Directors of the Company (the "Board")
recognizes that the possibility of a Change of Control (as hereinafter
defined in Section 2) exists and that the threat of or the occurrence of a
Change of Control can result in significant distractions of its key
management personnel because of the uncertainties inherent in such a
situation; and

       WHEREAS, the Board has determined that it is essential and in the
best interest of the Company and its shareholders to retain the services
of the Executive in the event of a threat or occurrence of a Change of
Control and to ensure his continued dedication and efforts in such event
without undue concern for his personal financial and employment security;
and

       WHEREAS, in order to induce the Executive to remain in the employ of
the Company, particularly in the event of a threat of or the occurrence of
a Change of Control, the Company desires to enter into this Agreement with
the Executive.

       NOW, THEREFORE, in consideration of the respective agreements of the
parties contained herein, it is agreed as follows:

       1.   Employment Term.   (a) The "Employment Term" shall commence on
the first date during the Protected Period (as defined in Section 1(c),
below) on which a Change of Control (as defined in Section 2, below)
occurs (the "Effective Date") and shall expire on the second anniversary
of the Effective Date; provided, however, that at the end of each day of
the Employment Term the Employment Term shall automatically be extended
for one (1) day unless either the Company or the Executive shall have
given written notice to the other at least thirty (30) days prior thereto
that the Employment Term shall not be so extended.

       (b)   Notwithstanding anything contained in this Agreement to the
contrary, if the Executive's employment is terminated prior to the
Effective Date and the Executive reasonably demonstrates that such
termination (i) was at the request of a third party who has indicated an
intention or taken steps reasonably calculated to effect a Change of
Control, or (ii) otherwise occurred in connection with or in anticipation
of a Change of Control, then for all purposes of this Agreement, the
Effective Date shall mean the date immediately prior to the date of such
termination of the Executive's employment.

        (c)   For purposes of this Agreement, the "Protected Period" shall be
the two (2) year period commencing on the date hereof; provided, however,
that at the end of each day the Protected Period shall be automatically
extended for one (1) day unless at least thirty (30) days prior thereto
the Company shall have given written notice to the Executive that the
Protected Period shall not be so extended; and provided, further, that
notwithstanding any such notice by the Company not to extend, the
Protected Period shall not end if prior to the expiration thereof any
third party has indicated an intention or taken steps reasonably
calculated to effect a Change of Control, in which event the Protected
Period shall end only after such third party publicly announces that it
has abandoned all efforts to effect a Change of Control.

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       2.   Change of Control.   For purposes of this Agreement, a "Change of
Control" shall mean the first to occur of the following:

       (a)   The acquisition by any individual, entity or "group" (within
the meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act
of 1934, as amended (the "Exchange Act")) of beneficial ownership (within
the meaning of Rule 13d-3 promulgated under the Exchange Act) of thirty-
three percent (33%) or more of either (i) the then outstanding shares of
common stock of the Company (the "Outstanding Company Common Stock") or
(ii) the combined voting power of the then outstanding voting securities
of the Company entitled to vote generally in the election of directors
(the "Outstanding Company Voting Securities"); provided, however, that the
following acquisitions of common stock shall not constitute a Change of
Control:   (i) any acquisition directly from the Company (excluding an
acquisition by virtue of the exercise of a conversion privilege or by one
person or a group of persons acting in concert), (ii) any acquisition by
the Company, (iii) any acquisition by any employee benefit plan (or
related trust) sponsored or maintained by the Company or any corporation
controlled by the Company or (iv) any acquisition by any corporation
pursuant to a reorganization, merger, statutory share exchange or
consolidation which would not be a Change of Control under subsection (c)
of this Section 2; or

        (b)   Individuals who, as of the date hereof, constitute the Board
(the "Incumbent Board") cease for any reason to constitute at least a
majority of the Board; provided, however, that any individual becoming a
director subsequent to the date hereof whose election, or nomination for
election by the Company's shareholders, was approved by a vote of at least
a majority of the directors then comprising the Incumbent Board shall be
considered as though such individual were a member of the Incumbent Board,
but excluding, for this purpose, any such individual whose initial
assumption of office occurs as a result of either an actual or threatened
"election contest" or other actual or threatened "solicitation" (as such
terms are used in Rule 14a-11 of Regulation 14A promulgated under the
Exchange Act) of proxies or consents by or on behalf of a person other
than the Incumbent Board; or

       (c)   Consummation of a reorganization, merger, statutory share
exchange or consolidation, unless, following such reorganization, merger,
statutory share exchange or consolidation, (i) more than two-thirds (2/3)
of, respectively, the then outstanding shares of common stock of the
corporation resulting from such reorganization, merger, statutory share
exchange or consolidation and the combined voting power of the then
outstanding voting securities of such corporation entitled to vote
generally in the election of directors is then beneficially owned,
directly or indirectly, by all or substantially all of the individuals and
entities who were the beneficial owners, respectively, of the Outstanding
Company Common Stock and Outstanding Company Voting Securities immediately
prior to such reorganization, merger, statutory share exchange or
consolidation in substantially the same proportions as their ownership,
immediately prior to such reorganization, merger, statutory share exchange
or consolidation, (ii) no person (excluding the Company, any employee
benefit plan (or related trust) of the Company or such corporation
resulting from such reorganization, merger, statutory share exchange or
consolidation and any person beneficially owning, immediately prior to
such reorganization, merger, statutory share exchange or consolidation,
directly or indirectly, thirty-three percent (33%) or more of the
Outstanding Company Common Stock or Outstanding Voting Securities, as the
case may be) beneficially owns, directly or indirectly, thirty-three
percent (33%) or more of, respectively, the then outstanding shares of
common stock of the corporation resulting from such reorganization,
merger, statutory share exchange or consolidation or the combined voting
power of the then outstanding voting securities of such corporation,
entitled to vote generally in the election of directors and (iii) at least
a majority of the members of the board of directors of the corporation
resulting from such reorganization, merger, statutory share exchange or
consolidation were members of the Incumbent Board at the time of the
execution of the initial agreement providing for such reorganization,
merger or consolidation; or

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       (d)   Consummation of (i) a complete liquidation or dissolution of
the Company or (ii) the sale or other disposition of all or substantially
all of the assets of the Company, other than to a corporation, with
respect to which following such sale or other disposition, (A) more than
two-thirds (2/3) of, respectively, the then outstanding shares of common
stock of such corporation and the combined voting power of the then
outstanding voting securities of such corporation entitled to vote
generally in the election of directors is then beneficially owned,
directly or indirectly, by all or substantially all of the individuals and
entities who were the beneficial owners, respectively, of the Outstanding
Company Common Stock and Outstanding Company Voting Securities immediately
prior to such sale or other disposition in substantially the same
proportion as their ownership, immediately prior to such sale or other
disposition, of the Outstanding Company Common Stock and Outstanding
Company Voting Securities, as the case may be, (B) no person (excluding
the Company and any employee benefit plan (or related trust) of the
Company or such corporation and any person beneficially owning,
immediately prior to such sale or other disposition, directly or
indirectly, thirty-three percent (33%) or more of the Outstanding Company
Common Stock or Outstanding Company Voting Securities, as the case may be)
beneficially owns, directly or indirectly, thirty-three percent (33%) or
more of, respectively, the then outstanding shares of common stock of such
corporation or the combined voting power of the then outstanding voting
securities of such corporation entitled to vote generally in the election
of directors and (C) at least a majority of the members of the board of
directors of such corporation were members of the Incumbent Board at the
time of the execution of the initial agreement or action of the Board
providing for such sale or other disposition of assets of the Company.

        3.   Employment.   (a) Subject to the provisions of Section 3, hereof,
the Company agrees to continue to employ the Executive and the Executive
agrees to remain in the employ of the Company during the Employment Term.
During the Employment Term, the Executive shall be employed in such
executive capacity as may be mutually agreed to by the parties.   During
the Employment Term, Executive's position (including status, offices,
titles and reporting requirements), authority, duties and responsibilities
shall be at least commensurate in all material respects with the most
significant of those held or assigned at any time during the twelve (12)
month period immediately preceding the Effective Date, and Executive's
services shall be performed at the location where Executive was employed
immediately preceding the Effective Date or at any office or location less
than thirty-five (35) miles from such location, unless mutually agreed to
in writing by the parties.

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       (b)   Excluding periods of vacation and sick leave to which the
Executive is entitled, during the Employment Term the Executive agrees to
devote full time attention to the business and affairs of the Company to
the extent necessary to discharge the responsibilities assigned to the
Executive hereunder, provided that the Executive may take reasonable
amounts of time to (i) serve on corporate, civil or charitable boards or
committees, and (ii) deliver lectures, fulfill speaking engagements or
teach at educational institutions, if such activities do not significantly
interfere with the performance of the Executive's responsibilities
hereunder.   It is expressly understood and agreed that to the extent any
such activities have been conducted by the Executive prior to the
Effective Date, the continued conduct of such activities (or the conduct
of activities similar in nature and scope) subsequent to the Effective
Date shall not thereafter be deemed to interfere with the performance of
Executive's responsibilities hereunder.

       4.   Compensation.   (a)   Base Salary.   During the Employment Term,
the Executive shall receive an annual base salary ("Annual Base Salary"),
which shall be paid at a monthly rate, at least equal to twelve (12) times
the highest monthly base salary paid or payable to the Executive by the
Company and its affiliated companies in respect of the twelve (12) month
period immediately preceding the month in which the Effective Date occurs,
including any amounts which were deferred under any plans of the Company
and its affiliated companies.   During the Employment Term, the Annual Base
Salary shall be reviewed at least annually and shall be increased at any
time and from time to time as shall be substantially consistent with
increases in base salary generally awarded in the ordinary course of
business to other peer executives of the Company and its affiliated
companies.   Any increase in Annual Base Salary shall not serve to limit or
reduce any other obligation to the Executive under this Agreement.   Annual
Base Salary shall not be reduced after any such increase and the term
Annual Base Salary as utilized in this Agreement shall refer to Annual
Base Salary as so increased.   As used in this Agreement, the term
"affiliated companies" shall include any company controlled by,
controlling or under common control with the Company.

       (b)   Annual Bonus.   In addition to Annual Base Salary, the Executive
shall be awarded, for each fiscal year ending during the Employment Term,
an annual bonus (the "Annual Bonus") in cash at least equal to the average
annualized (for any fiscal year consisting of less than twelve (12) full
months or with respect to which the Executive has been employed by the
Company for less than twelve (12) full months) bonuses paid or payable,
including any amounts which were deferred under any plans of the Company
and its affiliated companies, to the Executive by the Company and its
affiliated companies in respect of the three (3) fiscal years immediately
preceding the fiscal year in which the Effective Date occurs (the "Recent
Average Bonus").   Each such Annual Bonus shall be paid no later than
seventy-five (75) days after the end of the fiscal year for which the
Annual Bonus is awarded, unless the Executive shall elect to defer the
receipt of such Annual Bonus under any plan or arrangement of the Company
allowing therefor.

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       (c)   Incentive, Savings and Retirement Plans.   During the Employment
Term, the Executive shall be entitled to participate in all incentive,
savings and retirement plans, practices, policies and programs applicable
generally to other peer executives of the Company and its affiliated
companies, but in no event shall such plans, practices, policies and
programs provide the Executive with incentive opportunities (measured with
respect to both regular and special incentive opportunities, to the
extent, if any, that such distinction is applicable), savings
opportunities and retirement benefit opportunities, in each case, less
favorable, in the aggregate, than the most favorable of those provided by
the Company and its affiliated companies for the Executive under such
plans, practices, policies and programs as in effect at any time during
the twelve (12) month period immediately preceding the Effective Date, or,
if more favorable to the Executive, those provided generally at any time
after the Effective Date to other peer executives of the Company and its
affiliated companies.

       (d)   Benefit Plans.   During the Employment Term, the Executive
and/or the Executive's family, as the case may be, shall be eligible for
participation in and shall receive all benefits under benefit plans,
practices, policies and programs provided by the Company and its
affiliated companies (including, without limitation, medical, prescription
drug, dental, disability, salary continuance, employee life, group life,
accidental death and travel accident insurance plans and programs) to the
extent applicable generally to other peer executives of the Company and
its affiliated companies and their families; but in no event shall such
plans, practices, policies and programs provide the Executive with
benefits which are less favorable, in the aggregate, than the most
favorable of such plans, practices, policies and programs in effect for
the Executive and his family at any time during the twelve (12) month
period immediately preceding the Effective Date or, if more favorable to
the Executive, those provided generally at any time after the Effective
Date to other peer executives of the Company and its affiliated companies
and their families.

       (e)   Expenses.   During the Employment Term, the Executive shall be
entitled to receive prompt reimbursement for all reasonable expenses
incurred by the Executive in accordance with the most favorable policies,
practices and procedures of the Company and its affiliated companies in
effect for the Executive at any time during the twelve (12) month period
immediately preceding the Effective Date or, if more favorable to the
Executive, as in effect generally at any time thereafter with respect to
other peer executives of the Company and its affiliated companies.

       (f)   Fringe Benefits.   During the Employment Term, the Executive
shall be entitled to fringe benefits (including but not limited to Company
cars, club dues and physical examinations) in accordance with the most
favorable plans, practices, programs and policies of the Company and its
affiliated companies in effect for the Executive at any time during the
twelve (12) month period immediately preceding the Effective Date or, if
more favorable to the Executive, as in effect generally at any time
thereafter with respect to other peer executives of the Company and its
affiliated companies.

       (g)   Office and Support Staff.   During the Employment Term, the
Executive shall be entitled to an office or offices of a size and with
furnishings and other appointments, and to exclusive personal secretarial
and other assistance, in accordance with the most favorable of the
foregoing provided to the Executive by the Company and its affiliated
companies at any time during the twelve (12) month period immediately
preceding the Effective Date or, if more favorable to the Executive, as
provided generally at any time thereafter with respect to other peer
executives of the Company and its affiliated companies.

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       (h)   Vacation and Sick Leave.   During the Employment Term, the
Executive shall be entitled to paid vacation and sick leave (without loss
of pay) in accordance with the most favorable plans, policies, programs
and practices of the Company and its affiliated companies as in effect for
the Executive at any time during the twelve (12) month period immediately
preceding the Effective Date or, if more favorable to the Executive, as in
effect generally at any time thereafter with respect to other peer
executives of the Company and its affiliated companies.

       (i)   Restrictions.   As of the Effective Date, all restrictions
limiting the exercise, transferability or other incidents of ownership of
any outstanding award, including but not limited to restricted stock,
options, stock appreciation rights, or other property or rights of the
Company granted to the Executive shall lapse, and such awards shall become
fully vested and be held by the Executive free and clear of all such
restrictions.   This provision shall apply to all such property or rights
notwithstanding the provisions of any other plan or agreement, unless the
effect of the application of this provision to a particular right or
property would result in the loss of favorable securities law treatment
for participants under the plan pursuant to which the award was granted.

       5.   Termination of Employment.   During the Employment Term, the
Executive's employment hereunder may be terminated under the following
circumstances:

        (a)   Death or Disability.   The Executive's employment shall
terminate automatically upon the Executive's death during the Employment
Term.   If the Company determines in good faith that the Disability of the
Executive has occurred during the Employment Term (pursuant to the
definition of Disability set forth below), it may give to the Executive
written notice in accordance with Section 5 of this Agreement of its
intention to terminate the Executive's employment.   In such event, the
Executive's employment with the Company shall terminate effective on the
thirtieth (30th) day after receipt of such notice by the Executive (the
"Disability Effective Date"), provided that, within thirty (30) days after
such receipt, the Executive shall not have returned to full-time
performance of the Executive's duties.   For purposes of this Agreement,
"Disability" shall mean the absence of the Executive from the Executive's
duties with the Company on a full-time basis for one hundred eighty (180)
consecutive business days as a result of incapacity due to mental or
physical illness which is determined to be total and permanent by a
physician selected by the Company or its insurers and acceptable to the
Executive or the Executive's legal representative, provided if the parties
are unable to agree, the parties shall request the Dean of the Medical
College of Wisconsin to choose such physician.

       (b)   Cause.   The Company may terminate the Executive's employment
for "Cause."   A termination for Cause is a termination evidenced by a
resolution adopted in good faith by a majority of the Board that the
Executive (i) willfully, deliberately and continually failed to
substantially perform his duties under Section 3, above (other than a
failure resulting from the Executive's incapacity due to physical or
mental illness) which failure constitutes gross misconduct, and results in
and was intended to result in demonstrable material injury to the Company,
monetary or otherwise, or (ii) committed acts of fraud and dishonesty
constituting a felony, as determined by a final judgment or order of a
court of competent jurisdiction, and resulting or intended to result in
gain to or personal enrichment of the Executive at the Company's expense,
provided, however, that no termination of the Executive's employment shall
be for Cause as set forth in (i), above, until (a) Executive shall have
had at least sixty (60) days to cure any conduct or act alleged to provide
Cause for termination after a written notice of demand has been delivered
to the Executive specifying in detail the manner in which the Executive's
conduct violates this Agreement, and (b) the Executive shall have been
provided an opportunity to be heard by the Board (with the assistance of
the Executive's counsel if the Executive so desires).   No act, or failure
to act, on the Executive's part, shall be conside