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                                                                   EXHIBIT 10.21

                          CHANGE IN CONTROL AGREEMENT

                                  [THREE-YEAR]

         This CHANGE IN CONTROL AGREEMENT ("Agreement), effective as of July 15,
2002, by and between Southwest Bancorporation of Texas, Inc., a Texas
corporation (the "Company"), and Scott J. McLean (the "Executive");

                              W I T N E S S E T H:

         WHEREAS, the Executive is a senior executive of the Company's
wholly-owned subsidiary, Southwest Bank of Texas National Association (the
"Bank") and has made and/or is expected to make or continue to make major
contributions to the profitability, growth and financial strength of the Company
and the Bank;

         WHEREAS, references herein to the Executive's employment by the Company
shall also mean his or her employment by the Bank, and references herein to
payments of any nature to be made by the Company to the Executive shall mean
that either the Company will make such payments or it will cause the Bank to
make such payments to the Executive;

         WHEREAS, the Company desires to assure itself of both present and
future continuity of management in the event of a Change in Control (as defined
hereafter) and desires to establish certain minimum compensation rights of its
key senior executives, including the Executive, applicable in the event of a
Change in Control;

         WHEREAS, the Company wishes to ensure that its senior executives are
not practically disabled from discharging their duties upon a Change in Control;

         WHEREAS, this Agreement is not intended to alter materially the
compensation and benefits which the Executive could reasonably expect to receive
from the Company or the Bank absent a Change in Control and, accordingly,
although effective and binding as of the date hereof, this Agreement shall
become operative only upon the occurrence of a Change in Control; and

         WHEREAS, the Executive is willing to render services to the Company and
the Bank on the terms and subject to the conditions set forth in this Agreement;

         NOW, THEREFORE, the Company and the Executive agree as follows:

         1.       OPERATION OF AGREEMENT.

                  (a) This Agreement shall be effective and binding as of the
         Effective Date, but, anything in this Agreement to the contrary
         notwithstanding, this Agreement shall not be operative unless and until
         there shall have occurred a Change in Control. For purposes
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         of this Agreement, a "Change in Control" shall have occurred if at any
         time during the Term (as that term is hereafter defined) any of the
         following events shall occur:

                           (i) The Company is merged, consolidated or
                  reorganized into or with or sells all or substantially all of
                  its assets to another corporation or other legal person, and
                  as a result of such merger, consolidation, reorganization or
                  sale (i) less than a majority of the combined voting power of
                  the then-outstanding securities of such corporation or person
                  immediately after such transaction are held in the aggregate
                  by the holders of Voting Stock (as that term is hereinafter
                  defined) of the Company immediately prior to such transaction
                  and (ii) it is intended that persons serving as Directors of
                  the Company immediately prior to the transaction will
                  constitute none of or less than a majority of the Directors of
                  the other corporation or legal person after consummation of
                  the transaction; or

                           (ii) If during any one (1) year period, individuals
                  who at the beginning of any such period constitute the
                  Directors of the Company cease for any reason to constitute at
                  least a majority thereof, unless the election, or the
                  nomination for election by the Company's shareholders, of each
                  Director of the Company first elected during such period was
                  approved by a vote of at least two-thirds of the Directors of
                  the Company then still in office who were Directors of the
                  Company at the beginning of any such period.

                  (b)      Upon occurrence of a Change in Control at any time
         during the Term, this Agreement shall become immediately operative.

                  (c)      The period during which this Agreement shall be in
         effect (the "Term") shall commence as of the date hereof and shall
         expire as of the later of (i) the close of business on December 31,
         2002 and (ii) the expiration of the Period of Employment (as that term
         is hereinafter defined); provided, however, that (A) commencing on
         December 31, 2003 and the last day of each of the Company's Fiscal
         Years thereafter, the Term of this Agreement shall automatically be
         extended for an additional year unless, not later than the last day of
         the immediately preceding September, the Company or the Executive shall
         have given notice that it or he, as the case may be, does not wish to
         have the Term extended and (B) subject to Section 9 hereof, if, prior
         to a Change in Control, the Executive ceases for any reason to be an
         employee of the Company, thereupon the Term shall be deemed to have
         expired and this Agreement shall immediately terminate and be of no
         further effect.

         2.       EMPLOYMENT; PERIOD OF EMPLOYMENT.

                  (a)      Subject to the terms and conditions of this
         Agreement, upon the occurrence of a Change in Control, the Company
         shall continue the Executive in its employ and the Executive shall
         remain in the employ of the Company for the period set forth in Section
         2(b) hereof (the "Period of Employment"), in the position and with
         substantially the same duties and responsibilities that he had
         immediately prior to the Change in Control, or to which the Company and
         the Executive may hereafter mutually agree in writing. Throughout the
         Period of Employment, the Executive shall devote

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         substantially all of his time during normal business hours (subject to
         vacations, sick leave and other absences in accordance with the
         policies of the Company as in effect for senior executives immediately
         prior to the Change in Control) to the business and affairs of the
         Company, but nothing in this Agreement shall preclude the Executive
         from devoting reasonable periods of time during normal business hours
         to (i) serving as a director, trustee or member of or participant in
         any organization or business so long as such activity would not
         constitute Competitive Activity (as that term is hereafter defined) if
         conducted by the Executive after the Executive's Termination Date (as
         that term is hereafter defined), (ii) engaging in charitable and
         community activities, or (iii) managing his personal investments.

                  (b)      The Period of Employment shall commence on the date
         of an occurrence of a Change in Control and, subject only to the
         provisions of Section 4 hereof, shall continue until the earlier of (i)
         the expiration of the third anniversary of the occurrence of the Change
         in Control or (ii) the Executive's death; provided, however, that
         commencing on each anniversary of the Change in Control, the Period of
         Employment shall automatically be extended for an additional year
         unless, not later than 90 calendar days prior to such anniversary date,
         the Company or the Executive shall have given notice that it or he or
         she, as the case may be, does not wish to have the Term extended.

         3.       COMPENSATION DURING PERIOD OF EMPLOYMENT.

                  (a)      Upon the occurrence of a Change in Control, the
         Executive shall receive during the Period of Employment (i) annual base
         salary at a rate not less than the Executive's annual fixed or base
         compensation payable monthly or otherwise as in effect for senior
         executives of the Company immediately prior to the occurrence of a
         Change in Control or such higher rate as may be determined from time to
         time by the Board of Directors of the Company (the "Board") or the
         Compensation Committee thereof (the "Committee") (which base salary at
         such rate is herein referred to as "Base Pay") and (ii) an annual cash
         bonus in an amount determined for the Executive in accordance with the
         Company's incentive compensation plan or plans in effect at the time of
         the Change in Control or in accordance with an annual bonus, incentive,
         profit-sharing, performance, discretionary pay or similar policy, plan,
         program or arrangement of the Company or any successor thereto
         providing benefits at least as great as the benefits payable thereunder
         prior to the Change in Control ("Incentive Pay"); provided, however,
         that nothing herein shall preclude a change in the mix between Base Pay
         and Incentive Pay so long as the aggregate cash compensation received
         by the Executive in any one calendar year is not reduced in connection
         therewith or as a result thereof and, provided further, however, that
         in no event shall any increase in the Executive's aggregate cash
         compensation or any portion thereof in any way diminish any other
         obligation of the Company under this Agreement.

                  (b)      For his service pursuant to Section 2(a) hereof,
         during the Period of Employment the Executive shall, if and on the same
         basis as he participated therein immediately prior to the Change in
         Control, be a full participant in, and shall be entitled to the
         perquisites, benefits and service credit for benefits as provided under
         any and all employee retirement income and welfare benefit policies,
         plans, programs or

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         arrangements in which senior executives of the Company participate,
         including without limitation any stock option, stock purchase, stock
         appreciation, savings, pension, supplemental executive retirement or
         other retirement income or welfare benefit, deferred compensation,
         incentive compensation, group and/or executive life, accident, health,
         dental, medical/hospital or other insurance (whether funded by actual
         insurance or self-insured by the Company), disability, salary
         continuation, expense reimbursement and other employee benefit
         policies, plans, programs or arrangements that may now exist or any
         equivalent successor policies, plans, programs or arrangements that may
         be adopted hereafter by the Company providing perquisites, benefits and
         service credit for benefits at least as great as are payable thereunder
         prior to a Change in Control (collectively, "Employee Benefits");
         provided, however, that the Executive's rights thereunder shall be
         governed by the terms thereof and shall not be enlarged hereunder or
         otherwise affected hereby. Subject to the proviso in the immediately
         preceding sentence, if and to the extent such perquisites, benefits or
         service credit for benefits are not payable or provided under any such
         policy, plan, program or arrangement as a result of the amendment or
         termination thereof, then the Company shall itself pay or provide
         therefor. Nothing in this Agreement shall preclude improvement or
         enhancement of any such Employee Benefits, provided that no such
         improvement shall in any way diminish any other obligation of the
         Company under this Agreement.

                  (c)      The Company has determined that the amounts payable
         pursuant to this Section 3 constitute reasonable compensation.
         Accordingly, notwithstanding any other provision hereof, unless such
         action would be expressly prohibited by applicable law, if any amount
         paid or payable pursuant to this Section 3 is subject to the excise tax
         imposed by Section 4999 of the Internal Revenue Code of 1986, as
         amended (the "Code"), the Company will pay to the Executive an
         additional amount in cash equal to the amount necessary to cause the
         aggregate remuneration received by the Executive under this Section 3,
         including such additional cash payment (net of all federal, state and
         local income taxes and all taxes payable as the result of the
         application of Sections 280G and 4999 of the Code) to be equal to the
         aggregate remuneration the Executive would have received under this
         Section 3, excluding such additional payment (net of all federal, state
         and local income taxes), as if Sections 280G and 4999 of the Code (and
         any successor provisions thereto) had not been enacted into law.

         4.       TERMINATION FOLLOWING A CHANGE IN CONTROL.

                  (a)      In the event of the occurrence of a Change in
         Control, this Agreement may be terminated by the Company during the
         Period of Employment only upon the occurrence of one or more of the
         following events:

                           (i)      If the Executive is unable to perform the
                  essential functions of his job (with or without reasonable
                  accommodation) because he has become permanently disabled
                  within the meaning of, and actually begins to receive
                  disability benefits pursuant to, the long-term disability plan
                  in effect for senior executives or, if applicable, employees
                  of the Company immediately prior to the Change in Control; or

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                           (ii)     For "Cause", which for purposes of this
                  Agreement shall mean that, prior to any termination pursuant
                  to Section 4(b) hereof, the Executive shall have committed:

                                    (A)     Gross negligence or willful
                           misconduct in connection with his duties or in the
                           course of his employment with the Company;

                                    (B)     an act of fraud, embezzlement or
                           theft in connection with his duties or in the course
                           of his employment with the Company;

                                    (C)     intentional wrongful damage to
                           property of the Company;

                                    (D)     intentional wrongful disclosure of
                           secret processes or confidential information of the
                           Company;

                                    (E)     intentional wrongful engagement in
                           any Competitive Activity; or

                                    (F)     an act leading to a conviction of a
                           felony or a misdemeanor involving moral turpitude.

         For purposes of this Agreement, no act, or failure to act, on the part
of the Executive shall be deemed "intentional" if it was due primarily to an
error in judgment or negligence, but shall be deemed "intentional" only if done,
or omitted to be done, by the Executive not in good faith and without reasonable
belief that his action or omission was in the best interest of the Company.
Notwithstanding the foregoing, the Executive shall not be deemed to have been
terminated for "Cause" hereunder unless and until there shall have been
delivered to the Executive a copy of a resolution duly adopted by the
affirmative vote of not less than three-quarters of the Board then in office at
a meeting of the Board called and held for such purpose (after reasonable notice
to the Executive and an opportunity for the Executive, together with his
counsel, to be heard before the Board), finding that, in the good faith opinion
of the Board, the Executive had committed an act set forth above in this Section
4(a)(ii) and specifying the particulars thereof in detail. Nothing herein shall
limit the right of the Executive or his beneficiaries to contest the validity or
propriety of any such determination.

                  (b)      in the event of the occurrence of a Change in
         Control, this Agreement may be terminated by the Executive during the
         Period of Employment with the right to benefits as provided in Section
         5 hereof upon the occurrence of one or more of the following events:

                           (i)      Any termination by the Company of the
                  employment of the Executive for any reason other than for
                  Cause or as a result of the death of the Executive or by
                  reason of the Executive's disability and the actual receipt of
                  disability benefits in accordance with Section 4(a)(i) hereof;
                  or

                           (ii)     Termination by the Executive of his
                  employment with the Company within three years after the
                  Change in Control upon the occurrence of any of the following
                  events:


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                                    (A)     A reduction in the aggregate of the
                           Executive's Base Pay and Incentive Pay received from
                           the Company, or the termination of the Executive's
                           rights to any Employee Benefits to which he was
                           entitled immediately prior to the Change in Control
                           or a reduction in scope or value thereof without the
                           prior written consent of the Executive, any of which
                           is not remedied within 10 calendar days after receipt
                           by the Company of written notice from the Executive
                           of such change, reduction or termination, as the case
                           may be;

                                    (B)     The liquidation, dissolution,
                           merger, consolidation or reorganization of the
                           Company or transfer of all or a significant portion
                           of its business and/or assets, unless the successor
                           or successors (by liquidation, merger, consolidation,
                           reorganization or otherwise) to which all or a
                           significant portion of its business and/or assets
                           have been transferred (directly or by operation of
                           law) shall have assumed all duties and obligations of
                           the Company under this Agreement pursuant to Section
                           11 hereof;

                                    (C)     The Company requires the Executive
                           to have his principal location of work changed to any
                           location which is in excess of 50 miles from the
                           location thereof immediately prior to the Change in
                           Control or to travel away from his office in the
                           course of discharging his responsibilities or duties
                           hereunder significantly more (in terms of either
                           consecutive days or aggregate days in any calendar
                           year) than was required of him prior to the Change in
                           Control without, in either case, his prior consent;
                           or

                                    (D)     Any material breach of this
                           Agreement by the Company or any successor thereto.

                  (c)      A termination by the Company pursuant to Section 4(a)
         hereof or by the Executive pursuant to Section 4(b) hereof shall not
         affect any rights which the Executive may have pursuant to any
         agreement, policy, plan, program or arrangement of the Company
         providing Employee Benefits, which rights shall be governed by the
         terms thereof. If this Agreement or the employment of the Executive is
         terminated under circumstances in which the Executive is not entitled
         to any payments under Sections 3 or 5 hereof, the Executive shall have
         no further obligation or liability to the Company hereunder with
         respect to his prior or any future employment by the Company.

         5.       SEVERANCE COMPENSATION.

                  (a)      If, following the occurrence of a Change in Control,
         the Company shall terminate the Executive's employment during the
         Period of Employment other than pursuant to Section 4(a) hereof, or if
         the Executive shall terminate his employment pursuant to Section 4(b)
         hereof, the Company shall pay to the Executive the amount specified in
         Section 5(a)(i) hereof within ten business days after the date (the
         "Termination Date") that the Executive's employment is terminated (the
         effective date of

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         which shall be the date of termination, or such other date that may be
         specified by the Executive if the termination is pursuant to Section
         4(b) hereof):

                           (i)      In lieu of any further payments to the
                  Executive for periods subsequent to the Termination Date, but
                  without affecting the rights of the Executive referred to in
                  Section 5(b) hereof, a lump sum payment (the "Severance
                  Payment") in an amount equal to the present value (using a
                  discount rate required to be utilized for purposes of
                  computations under Section 280G of the Code or any successor
                  provision thereto, or if no such rate is so required to be
                  used, a rate equal to the then-applicable interest rate
                  prescribed by the Pension Benefit Guaranty Corporation for
                  benefit valuations in connection with non-multiemployer
                  pension plan terminations assuming the immediate commencement
                  of benefit payments (the "Discount Rate")) of the sum of (A)
                  the aggregate Base Pay (at the highest rate in effect during
                  the Term prior to the Termination Date) for three years, plus
                  (B) the aggregate Incentive Pay for three years (based upon
                  the greatest amount of Incentive Pay paid or payable to the
                  Executive for any year during the three calendar years
                  preceding the year in which the Termination Date occurs);
                  provided, however, that the Severance Payment shall be reduced
                  so that the aggregate "present value" (as determined under
                  Section 280G of the Code or any successor provision thereto)
                  of the amount otherwise payable hereunder, when added to the
                  "present value" (as determined under Section 280G of the Code
                  or any successor provision thereto) of any other "parachute
                  payments" (as that term is defined in Section 280G of the Code
                  (without regard to Section 280G(b)(2)(A)(ii) thereof) or any
                  successor provision thereto) from the Company, shall not
                  exceed an amount (the "299% Amount") equal to 299% of the
                  Executive's "base amount" (as that term is defined in Section
                  280G of the Code or any successor provision thereto) so that
                  no portion of such amounts received by the Executive shall be
                  subject to the excise tax imposed by Section 4999 of the Code
                  if and only if such reduction produces a better net after-tax
                  position for the Executive (taking into account any applicable
                  excise tax under Section 4999 of the Code and any other
                  applicable taxes) than the full payment of the Severance
                  Payments and all other payments and benefits provided for in
                  this Agreement or otherwise would have produced.

                           (ii)     The determination of whether any amount
                  otherwise payable under Section 5(a)(i) causes the 299% Amount
                  to be exceeded shall be made, if requested by the Executive or
                  the Company, by tax counsel selected by the Company and
                  reasonably acceptable to the Executive. The costs of obtaining
                  such determination shall be borne by the Company. The fact
                  that the Executive shall have his right to the Severance
                  Payment reduced as a result of the existence of the
                  limitations contained in this Section 5(a) shall not limit or
                  otherwise affect any rights of the Executive to any Employee
                  Benefit, or other right arising other than pursuant to this
                  Agreement. Without limiting the generality of the foregoing,
                  upon the Executive's termination of employment as provided in
                  this Section 5, the Company shall pay over to him all vested
                  benefits to which he is entitled under and in accordance with
                  the terms of the Company's employee savings, stock

<PAGE>

                  ownership, supplemental executive retirement and similar Plans
                  in the event such payments are not otherwise made in
                  accordance with the terms of such plans.

                           (iii)    Except to the extent that the payments or
                  benefits pursuant to this Section 5(a)(iii) would result in a
                  reduction of the amount of the Severance Payment because they
                  would exceed the 299% Amount, (A) for the remainder of the
                  Period of Employment the Company shall arrange to provide the
                  Executive with Employee Benefits substantially similar to
                  those which the Executive was receiving or entitled to receive
                  immediately prior to the Termination Date (and if and to the
                  extent that such benefits shall not or cannot be paid or
                  provided under any policy, plan, program or arrangement of the
                  Company solely due to the fact that the Executive is no longer
                  an officer or employee of the Company, then the Company shall
                  itself pay or provide for the payment to the Executive, his
                  dependents and beneficiaries, such Employee Benefits) and (B)
                  without limiting the generality of the foregoing, the
                  remainder of the Period of Employment shall be considered
                  service with the Company for the purpose of service credits
                  under the Company's retirement income, supplemental executive
                  retirement and other benefit plans of the Company applicable
                  to the Executive or his beneficiaries immediately prior to the
                  Termination Date. Without otherwise limiting the purposes or
                  effect of Section 6 hereof, Employee Benefits payable to the
                  Executive pursuant to this Section 5(a)(iii) by reason of any
                  "welfare benefit plan" of the Company (as the term "welfare
                  benefit plan" is defined in Section 3(1) of the Employee
                  Retirement Income Security Act of 1974, as amended) shall be
                  reduced to the extent comparable welfare benefits are actually
                  received by the Executive from another employer during such
                  period following the Executive's Termination Date until the
                  expiration of the Period of Employment.

                           (iv)     Notwithstanding any provision of the Section
                  5(a) to the contrary, in the event the benefits intended to be
                  provided to the Executive pursuant to Section 5(a)(iii) hereof
                  are required to be reduced in whole or in part because the
                  value of such Employee Benefits, when added to the amount of
                  the Severance Payment under Section 5(a)(i), would exceed 299%
                  Amount, the Executive shall have the option to elect to
                  receive, in lieu of all or a portion of the Severance Payment
                  provided in Section 5(a)(i) hereof, one or more Employee
                  Benefits, provided that (A) prior to the receipt of any
                  payment under Section 5(a)(i) hereof, the Executive Benefit or
                  Employee Benefits so elected to be received, and (B) in no
                  event shall the "aggregate present value of the payments in
                  the nature of compensation" (as that phrase is used in Section
                  280G of the Code) received by the Executive as a result of the
                  receipt of such Employee Benefits, when added to the remaining
                  portion of the Severance Payment, if any, to be received by
                  the Executive, exceed the 299% Amount.

                           (v)      In addition to all other compensation due to
                  the Executive, the following shall occur immediately following
                  the occurrence of a Change in Control:

<PAGE>

                                    (A)     all Company stock options held by
                           the Executive prior to a Change in Control shall
                           become fully exercisable, regardless of whether or
                           not the vesting conditions set forth in the relevant
                           stock option agreements have been satisfied in full;
                           and

                                    (B)     all restrictions on any restricted
                           Company stock granted to the Executive prior to a
                           Change in Control shall be removed and the stock
                           shall be freely transferable, regardless of whether
                           the conditions set forth in the relevant restricted
                           stock agreements have been satisfied in full.

                  (b)      Upon written notice given by the Executive to the
         Company prior to the receipt of any payment pursuant to Section 5(a)
         hereof, the Executive, at his sole option, without reduction to reflect
         the present value of such amounts as aforesaid, may elect to have all
         or any of the Severance Payment payable pursuant to Section 5(a)(i)
         hereof paid to him on a quarterly or monthly basis during the remainder
         of the Period of Employment.

                  (c)      There shall be no right of set-off or counterclaim in
         respect of any claim, debt or obligation against any payment to or
         benefit for the Executive provided for in this Agreement.

                  (d)      Without limiting the rights of the Executive at law
         or in equity, if the Company fails to make any payment required to be
         made hereunder on a timely basis, the Company shall pay interest on the
         amount thereof at an annualized rate of interest equal to the
         then-applicable Discount Rate or, if lesser, the highest rate allowed
         by applicable usury laws.

         6.       NO MITIGATION OBLIGATION. The Company hereby acknowledges that
it will be difficult, and may be impossible, for the Executive to find
reasonably comparable employment following the Termination Date and that the
non-competition covenant contained in Section 7 hereof will further limit the
employment opportunities for the Executive. Accordingly, the parties hereto
expressly agree that the payment of the severance compensation by the Company to
the Executive in accordance with the terms of this Agreement will be liquidated
damages, and that the Executive shall not be required to mitigate the amount of
any payment provided for in this Agreement by seeking other employment or
otherwise, nor shall any profits, income, earnings or other benefits from any
source whatsoever create any mitigation, offset, reduction or any other
obligation on the part of the Executive hereunder or otherwise, except as
expressly provided in Section 5(a)(iii) hereof.

         7.       COMPETITIVE ACTIVITY. During a period ending one year
following the Termination Date, if the Executive shall have received or shall be
receiving benefits under Section 5(a) hereof, the Executive shall not, without
the prior written consent by the Company, directly or indirectly engage in the
business of commercial banking in competition with the business of the Company
within Harris County, Fort Bend County and Montgomery County, Texas and any
other geographical area served by the Company during the twelve (12) month
period immediately preceding termination of employment nor will the Executive
engage, within this geographical area, in the design, development, distribution,
or sale of a product or service in

<PAGE>

competition with any product or service being marketed or planned by the Company
at such time, the plans, designs or specifications of which have been revealed
to the Executive. The Executive acknowledges that these limited prohibitions are
reasonable as to time, geographical area and scope of activities to be
restrained and that the limited prohibitions do not impose a greater restraint
than is necessary to protect the Company's goodwill, proprietary information and
other business interests. "Competitive Activity" shall mean the prohibitions set
forth above in this Section 7, but shall not include (i) the mere ownership of
securities in any such enterprise and exercise of rights appurtenant thereto or
(ii) participation in management of any such enterprise or business operation
thereof other than in connection with the competitive operation of such
enterprise.

         8.       LEGAL FEES AND EXPENSES. In the event of a breach of this
Agreement by the Company, it is the intent of the Company that the Executive not
be required to incur the expenses associated with the enforcement of his rights
under this Agreement by litigation or other legal action because the cost and
expense thereof would substantially detract from the benefits intended to be
extended to the Executive hereunder. Accordingly, if the Company fails to comply
with any of its obligations under this Agreement or in the event that the
Company or any other person takes any action to declare this Agreement void or
unenforceable, or institutes any litigation designed to deny, or to recover
from, the Executive the benefits intended to be provided to the Executive
hereunder, the Company irrevocably authorizes the Executive from time to time to
retain counsel of his choice, at the expense of the Company as hereafter
provided, to represent the Executive in connection with the initiation or
defense of any litigation or other legal action, whether by or against the
Company or any Director, officer, shareholder or other person affiliated with
the Company, in any jurisdiction. Notwithstanding any existing or prior
attorney-client relationship between the Company and such counsel, the Company
irrevocably consents to the Executive's entering into an attorney-client
relationship with such counsel (other than Vinson & Elkins L.L.P.), and in that
connection the Company and the Executive agree that a confidential relationship
shall exist between the Executive and such counsel. The Company shall pay or
cause to be paid and shall be solely responsible for any and all attorneys' and
related fees and expenses incurred by the Executive as a result of the Company's
failure to perform this Agreement or any provision thereof or as a result of the
Company or any person contesting the validity or enforceability of this
Agreement or any provision thereof as aforesaid. If the Company should prevail
in any litigation regarding this Agreement, however, the Company shall not be
responsible for any attorneys' and related fees and expenses incurred by
Employee in connection with such litigation.

         9.       EMPLOYMENT RIGHTS. Nothing expressed or implied in this
Agreement shall create any right or duty on the part of the Company or the
Executive to have the Executive remain in the employment of the Company prior to
any Change in Control; provided, however, that any termination of employment of
the Executive or removal of the Executive as an Officer of the Company following
the commencement of any discussion with a third person that ultimately results
in a Change in Control shall be deemed to be a termination or removal of the
Executive after a Change in Control for purposes of this Agreement.

         10.      WITHHOLDING OF TAXES. The Company may withhold from any
amounts payable under this Agreement all federal, state, city or other taxes as
shall be required pursuant to any law or government regulation or ruling.

<PAGE>

         11.      SUCCESSORS AND BINDING AGREEMENT.

                  (a)      The Company shall require any successor (whether
         direct or indirect, by purchase, merger, consolidation, reorganization
         or otherwise) to all or substantially all of the business and/or assets
         of the Company to execute an agreement pursuant to which the successor
         expressly assumes all of the liabilities and obligations of the Company
         hereunder and agrees to perform this Agreement in the same manner and
         to the same extent the Company would be required to perform if no such
         succession had taken place. This Agreement shall be binding upon and
         inure to the benefit of the Company and any successor to the Company,
         including without limitation any persons acquiring directly or
         indirectly all or substantially all of the business and/or assets of
         the Company whether by purchase, merger, consolidation, reorganization
         or otherwise (and such successor shall thereafter be deemed the
         "Company" for the purposes of this Agreement), but shall not otherwise
         be assignable, transferable or delegable by the Company.

                  (b)      This Agreement shall inure to the benefit of and be
         enforceable by the Executive's personal or legal representatives,
         executors, administrators, successors, heirs, distributes and/or
         legatees.

                  (c)      This Agreement is personal in nature and neither of
         the parties hereto shall, without the consent of the other, assign,
         transfer or delegate this Agreement or any rights or obligations
         hereunder except as expressly provided in Section 11(a) hereof. Without
         limiting the generality of the foregoing, the Executive's right to
         receive payments hereunder shall not be assignable, transferable or
         delegable, whether by pledge, creation of a security interest or
         otherwise, other than by a transfer by the Executive's will or by the
         laws of descent and distribution and, in the event of any attempted
         assignment or transfer contrary to this Section 11(c), the Company
         shall have no liability to pay any amount so attempted to be assigned,
         transferred or delegated.

                  (d)      The Company and the Executive recognize that each
         party will have no adequate remedy at law for breach by the other of
         any of the agreements contained herein and, in the event of any such
         breach, the Company and the Executive hereby agree and consent that the
         other shall be entitled to a decree of specific performance, mandamus
         or other appropriate remedy to enforce performance of this Agreement.

         12.      NOTICE. For all purposes of this Agreement, all communications
provided for herein shall be in writing and shall be deemed to have been duly
given when delivered or three business days after having been mailed by United
States registered or certified mail, return receipt requested, postage prepaid,
addressed to the Company (to the attention of the Secretary of the Company) at
its principal executive office and to the Executive at his principal residence,
or to such other address as any party may have furnished to the other in writing
and in accordance herewith, except that notices of change of address shall be
effective only upon receipt.

         13.      GOVERNING LAW. The validity, interpretation, construction and
performance of this Agreement shall be governed by the laws of the State of
Texas, without giving effect to the principles of conflict of laws of such
State.

<PAGE>

         14.      VALIDITY. If any provision of this Agreement or the
application of any provision hereof to any person or circumstances is held
invalid, unenforceable or otherwise illegal, the remainder of this Agreement and
the application of such provision to any other person or circumstances shall not
be affected, and the provision so held to be invalid, unenforceable or otherwise
illegal shall be reformed to the extent (and only to the extent) necessary to
make it enforceable, valid and legal.

         15.      MISCELLANEOUS. No provisions of this Agreement may be
modified, waived or discharged unless such waiver, modification or discharge is
agreed to in writing signed by the Executive and the Company. No waiver by
either party hereto at any time of any breach by the other party hereto or
compliance with any condition or provision of this Agreement to be performed by
such other party shall be deemed a waiver of similar or dissimilar provisions or
conditions at the same or at any prior or subsequent time. No agreements or
representations, oral or otherwise, expressed or implied with respect to the
subject matter hereof have been made by either party which are not set forth
expressly in this Agreement.

         16.      PRIOR AGREEMENTS. This Agreement is voluntarily entered into
and supersedes and takes the place of any prior change in control, severance or
employment agreements between the parties hereto. The parties hereto expressly
agree and hereby declare that any and all prior change in control, severance or
employment agreements between the parties are terminated and of no force or
effect.

         17.      COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original but all of which
together will constitute one and the same agreement.

         IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed and delivered as of the date first above written.

                                        SOUTHWEST BANCORPORATION OF TEXAS, INC.

                                        By:   /s/ Paul B. Murphy
                                        -----------------------------------

                                        EXECUTIVE:

                                        /s/ Scott J. McLean
                                        -----------------------------------
                                        Scott J. McLean