EXHIBIT 10.24

TAX GROSS UP AGREEMENT

This Tax Gross Up Agreement (this “Agreement”) is entered into this 25th day of
August, 2006 by and between MB Financial, Inc. (the “Company”) and Richard M.
Rieser, Jr. (the “Employee”).

WHEREAS, the Company and the Employee have entered into an Employment Agreement
on the date hereof (the “Employment Agreement”);

WHEREAS, it is possible that the Employee may receive or be entitled to receive
payments or benefits from the Company and/or its subsidiaries and/or
predecessors (“Payments”) in connection with or arising from a Change in Control
(as hereinafter defined), or an associated event linked to a Change in Control,
which could result in the receipt by the Employee of an “excess parachute
payment” (as such term is defined in Section 280G(b)(1) of the Internal Revenue
Code of 1986, as amended (the “Code”));

WHEREAS, if the Employee receives an “excess parachute payment” from the Company
and/or any of its subsidiaries, the Employee will be subject to a 20% excise tax
under Section 4999 of the Code;

WHEREAS, it is the intention of the parties that the Employee should not be
subject to any penalty tax by virtue of any Payments unless his employment
ceases due to a Termination for Cause or a Voluntary Termination (as such terms
are hereinafter defined); and

WHEREAS, it has been agreed to by the Company and the Employee that if the
Employee is subject to an excise tax under Section 4999 by virtue of any
Payments, then the Company shall make an additional cash payment or cash
payments to the Employee that will provide the Employee with sufficient funds,
on an after tax basis, to pay the penalty tax imposed on any such Payment and
the penalty tax imposed on the additional cash payment or payments, unless the
Employee’s employment ceases due to a Termination for Cause (as defined in the
Employment Agreement) or a Voluntary Termination (as defined in the Employment
Agreement) prior to age 65, in either case during the Term (as defined in the
Employment Agreement) and prior to or within one year following a Change in
Control.

NOW, THEREFORE, in consideration of the premises, and for other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged by the parties, it is agreed by the parties as follows:

1. Definition of Certain Terms. (a) “Change in Control” means (i) a change in
ownership of the Company or a significant financial institution subsidiary of
the Company that independently or in conjunction with another event (such as a
termination of the employment of the Employee) would result in the Employee
receiving an “excess parachute payment” under Section 280G of the Code; or (ii)
in the event the Employee experiences an Involuntary Termination (as defined in
the Employment Agreement) within two years from the date hereof, the change in
ownership of First Oak Brook Bancshares, Inc. arising from the acquisition of
First Oak Brook Bancshares, Inc. by the Company.

2. Adjusted Gross Up Payment and Additional Gross Up Payment. In the event that
any Payments would be subject to excise tax under Section 4999 of the Code (such
excise tax and any penalties and interest collectively, the “Penalty Tax”), the
Company shall pay to the Employee in cash an additional amount equal to the
Adjusted Gross Up Payment. The “Adjusted Gross Up Payment” shall be an amount
such that after payment by the Employee of all federal, state, local, employment
and medicare taxes thereon (and any penalties and interest with respect
thereto), the Employee retains on an after tax basis a portion of such amount
equal to the aggregate of 100% of the Penalty Tax imposed upon the Payment and
100% of the Penalty Tax imposed upon the Adjusted Gross Up Payment. For purposes
of determining the amount of the Adjusted Gross Up Payment, the value of any
non-cash benefits and deferred payments or benefits subject to the Penalty Tax
shall be determined by the Company's independent auditors in accordance with the
principles of Section 280G(d)(3) and (4) of the Code. The Adjusted Gross Up
Payment less required tax withholding shall be paid by the Company to the
Employee on the earlier of (i) the date the Company and/or any of its
subsidiaries is required to withhold tax with respect to any Payment or (ii) the
date any Penalty Tax is required to be paid by the Employee. In the event that,
after the Adjusted Gross Up Payment is made, the Employee becomes entitled to
receive a refund of any portion of the Penalty Tax, the Employee shall promptly
pay to the Company 100% of such Penalty Tax refund attributable to the Payment
(together with 100% of any interest paid or credited thereon by the Internal
Revenue Service) and 100% of the Penalty Tax refund attributable to the Adjusted
Gross Up Payment (together with 100% of any interest paid or credited thereon by
the Internal Revenue Service). As a result of the uncertainty regarding the
application of Section 4999 of the Code, it is possible that the Internal
Revenue Service may assert that the Penalty Tax due is in excess of the amount
of the anticipated Penalty Tax used in calculating the Adjusted Gross Up Payment
(such excess amount is hereafter referred to as the “Underpayment”). In such
event, the Company shall pay to the Employee, in immediately available funds, at
the time the Underpayment is assessed or otherwise determined, an additional
amount equal to the Additional Gross Up Payment. The “Additional Gross Up
Payment” shall be an amount such that after payment by the Employee of all
federal, state, local, employment and medicare taxes thereon (and any penalties
and interest with respect thereto), the Employee retains on an after tax basis a
portion of such amount equal to the aggregate of (i) 100% of the portion of the
Underpayment attributable to the Payment, (ii) 100% of the portion of the
Underpayment attributable to the Adjusted Gross Up Payment and (iii) 100% of the
Penalty Tax imposed on the Additional Gross Up Payment. Notwithstanding the
foregoing, in the event the Employee experiences a Termination for Cause or a
Voluntary Termination, in either case during the Term and prior to or within one
year after a Change in Control, then in that event, (a) if such termination
occurs prior to the payment to the Employee of any Adjusted Gross Up Payment,
then the Employee shall not be entitled to receive any Adjusted Gross Up Payment
or Additional Gross Up Payment or (b) if such termination occurs after an
Adjusted Gross Up Payment has been made to the Employee, then the Employee shall
remit to the Company within five days after such termination the full amount of
the Adjusted Gross Up Payment and Additional Gross Up Payments thereto for paid
to the Employee and the Employee shall not be entitled to receive any other
payments pursuant to this Section 2. However, if it is later determined that the
Employee’s Termination for Cause was improper, then the Employee shall be
entitled to receive the Adjusted Gross Up Payment and Additional Gross Up
Payment, together with any actual consequential and incidental damages arising
from the delay in his receipt of such payments.

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3. Final Agreement and Binding Effect. This Agreement represents the final
agreement between the parties relating to the subject matter hereof, and may
only be modified or amended by subsequent writing that is executed by the
parties. This Agreement shall be binding upon and inure to the benefit of the
Company, its successors and assigns and the Employee and his or her estate,
heirs and beneficiaries.

4. Governing Law. This Agreement shall be governed by the laws of the State of
Illinois.

5. Counterparts. This Agreement may be executed in one or more counterparts,
each of which shall be deemed an original.

This Agreement has been executed by the parties hereto as of the date first
above written.

                MB FINANCIAL, INC.

                By: ______________________________
                Authorized Officer

                EMPLOYEE
    

                By: _______________________________
                Richard M. Rieser, Jr.
 
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