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                     SOUTHWEST BANCORPORATION OF TEXAS, INC.
                        NON-EMPLOYEE DIRECTOR STOCK PLAN


         1. PURPOSE. The SOUTHWEST BANCORPORATION OF TEXAS, INC. NON-EMPLOYEE
DIRECTOR STOCK PLAN is intended to allow non-employee directors of Southwest
Bancorporation of Texas, Inc. (the "Company") and/or of Southwest Bank of Texas
National Association (the "Bank") to acquire or increase a proprietary interest
in the Company by providing the opportunity to receive shares of the Company's
common stock in lieu of certain cash compensation.

         2. DEFINITIONS. Where the following words and phrases are used in the
Plan, they shall have the respective meanings set forth below, unless the
context clearly indicates to the contrary:

            (a) "Account" means an individual account for each Non-Employee
         Director which is credited with shares of Stock in accordance with such
         Non-Employee Director's Stock Conversion Elections and which is
         maintained pursuant to the terms of paragraph 6(c).

            (b) "Affiliate" means any corporation, partnership, limited
         liability company or partnership, association, trust or other
         organization which, directly or indirectly, controls, is controlled by,
         or is under common control with, the Company. For purposes of the
         preceding sentence, "control" (including, with correlative meanings,
         the terms "controlled by" and "under common control with"), as used
         with respect to any entity or organization, shall mean the possession,
         directly or indirectly, of the power (i) to vote more than 50% of the
         securities having ordinary voting power for the election of directors
         of the controlled entity or organization, or (ii) to direct or cause
         the direction of the management and policies of the controlled entity
         or organization, whether through the ownership of voting securities or
         by contract or otherwise.

            (c) "Bank" means Southwest Bank of Texas National Association, a
         national banking association.

            (d) "Board" means the Board of Directors of the Company.

            (e) "Committee" means a committee appointed from time to time by the
         Board to administer the Plan as provided in paragraph 3.

            (f) "Company" means Southwest Bancorporation of Texas, Inc., a Texas
         corporation.

            (g) "Custodian" means the custodian selected by the Committee to
         maintain Non-Employee Directors' Accounts in accordance with the terms
         of the Plan.
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            (h) "Election Period" means, with respect to the 2001 Plan Year, the
         period beginning January 1, 2001 and ending March 31, 2001, and with
         respect to all subsequent Plan Years, the period beginning on the
         January 1 of such Plan Year and ending on the January 31 of such Plan
         Year.

            (i) "Eligible Compensation" means, with respect to a Plan Year, the
         sum total of cash compensation that is payable to a Non-Employee
         Director by the Company or by the Bank in exchange for such
         Non-Employee Director's committee chairmanship and/or attendance at one
         or more committee meetings and/or attendance at one or more meetings of
         the board of directors of the Company and/or of the Bank during such
         Plan Year.

            (j) "Non-Employee Director" means an individual (who is not in an
         employment relationship with the Company, the Bank or any Affiliate)
         elected to the board of directors of the Company and/or of the Bank by
         its stockholders or by such board of directors under applicable
         corporate law who is serving on such board of directors on the date the
         Plan is adopted by the Board or is elected to such board of directors
         after such date.

            (k) "Plan" means this Southwest Bancorporation of Texas, Inc.
         Non-Employee Director Stock Plan, as amended from time to time.

            (l) "Plan Year" means the twelve-consecutive month period commencing
         January 1 of each year.

            (m) "Stock" means the common stock, par value $1.00 per share of the
         Company, or any security into which such Stock may be changed by reason
         of any transaction or event of the type described in paragraph 9.

            (n) "Stock Conversion Election" means an election made pursuant to
         paragraph 6.

            (o) "Termination of Service" means the termination of a Non-Employee
         Director's service as a member of the board of directors of the Company
         and/or of the Bank for any reason.

         3. ADMINISTRATION OF THE PLAN. The Plan shall be administered by the
Committee, the members of which shall be appointed from time to time by the
Board. Each member of the Committee shall serve for a term commencing on a date
specified by the Board and continuing until he dies, resigns, or is removed from
office by the Board. Subject to the provisions of the Plan, the Committee shall
interpret the Plan and all Stock Conversion Elections under the Plan, make such
rules as it deems necessary for the proper administration of the Plan, and make
all other determinations necessary or advisable for the administration of the
Plan. In addition, the Committee shall correct any defect or supply any omission
or reconcile any inconsistency in the Plan, or in any Stock Conversion Election
under the Plan, in the manner and to the extent that the Committee deems

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desirable to carry the Plan or any Stock Conversion Election into effect. The
Committee shall, in its sole discretion, make such decisions or determinations
and take such actions as it shall deem necessary, advisable, convenient or
proper, and all such decisions, determinations and actions taken or made by the
Committee pursuant to this and the other paragraphs of the Plan shall be
conclusive and binding on all parties. The Committee shall not be liable for any
decision, determination or action taken in good faith in connection with the
administration of the Plan. The Committee shall have the authority to delegate
routine day-to-day administration of the Plan to such officers and employees of
the Company as the Committee deems appropriate.

         4. ELIGIBILITY. Each individual who is a Non-Employee Director during a
Plan Year and who has not incurred a Termination of Service shall be eligible to
execute a Stock Conversion Election with respect to his Eligible Compensation
for such Plan Year.

         5. STOCK SUBJECT TO THE PLAN. Subject to the provisions of paragraph 9,
the aggregate number of shares of Stock which may be delivered to the Custodian
pursuant to Stock Conversion Elections under the Plan shall not exceed 25,000
shares, which shares may be unissued shares or reacquired shares, including
shares bought on the market or otherwise for purposes of the Plan. Any shares
that are not delivered to the Custodian pursuant to Stock Conversion Elections
previously executed upon the termination of the Plan shall cease to be subject
to the Plan.

         6. STOCK CONVERSION ELECTIONS.

            (a) IN GENERAL. For each Plan Year, a Non-Employee Director who
meets the eligibility requirements of paragraph 4 may execute a Stock Conversion
Election whereby such Non-Employee Director elects to convert his Eligible
Compensation for such Plan Year into nonforfeitable shares of Stock in
accordance with subparagraph (b) below. A Non-Employee Director's Stock
Conversion Election for a Plan Year must be made by executing and delivering to
the Committee during the Election Period for such Plan Year the form prescribed
by the Committee for such purpose. A Stock Conversion Election for a Plan Year
shall be with respect to such Plan Year only and shall not remain in force and
effect for any subsequent Plan Year.

            (b) NUMBER OF SHARES. Upon a Non-Employee Director's execution of a
Stock Conversion Election with respect to a Plan Year in accordance with
subparagraph (a) above, such Non-Employee Director's Eligible Compensation for
such Plan Year shall be converted as paid into a number of nonforfeitable shares
of Stock equal to the quotient of (i) an amount equal to such Non-Employee
Director's Eligible Compensation as paid during such Plan Year, divided by (ii)
the fair market value of a share of Stock on the applicable date of payment. For
purposes of the Plan, the fair market value of a share of Stock on a particular
date shall be equal to the closing price of the Stock on the National Market
System of NASDAQ on that date (or, if no shares of Stock have been traded on
that date, on the next regular business date on which shares of Stock are so
traded).

            (c) DELIVERY OF SHARE CERTIFICATES; NON-EMPLOYEE DIRECTORS'
ACCOUNTS. As soon as practicable following each date of payment of Eligible
Compensation, the Company shall

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deliver to the Custodian certificates representing (or shall otherwise cause to
be credited to the account of the Custodian) the total number of whole shares of
Stock resulting from the aggregate Non-Employee Director's Stock Conversion
Elections applicable thereto. Any remaining amount representing a fractional
share with respect to such aggregate Non-Employee Director's Stock Conversion
Elections shall not be certificated (or otherwise so credited) but shall be paid
to the Custodian by the Company in cash. The Custodian shall establish and
maintain an Account for each such Non-Employee Director and shall credit each
such Account with any shares of Stock (both whole and fractional) delivered by
the Company to the Custodian on each such Non-Employee Director's behalf. The
Custodian shall keep accurate records of the number and value of shares of Stock
credited to each Non-Employee Director's Account, and shall provide each such
Non-Employee Director with quarterly or such other periodic statements with
respect thereto as may be directed by the Committee.

            (d) TRANSFER RESTRICTIONS. A Non-Employee Director may not sell,
assign, pledge, exchange, hypothecate or otherwise transfer, encumber or dispose
of the shares of Stock in his Account prior to such Non-Employee Director's
Termination of Service; provided, however, that such transfer restrictions shall
not apply to the transfer, exchange or conversion of such shares of Stock by
reason of any transaction or event of the type described in paragraph 9, but the
stock, securities or other property (other than cash) received upon any such
transfer, exchange or conversion shall also become subject to the same transfer
restrictions applicable to the original shares of Stock, and shall be held by
the Custodian in such Non-Employee Director's Account, pursuant to the
provisions hereof. Upon the occurrence of a Non-Employee Director's Termination
of Service, the transfer restrictions set forth in this subparagraph 6(d) shall
cease to apply to the shares of Stock held in such Non-Employee Director's
Account as provided in paragraph 7 below. The Committee may cause the Stock
delivered to the Custodian pursuant to Stock Conversion Elections under the Plan
and held in Non-Employee Directors' Accounts to bear such legends or other
appropriate restrictions, and the Committee may take such other actions, as it
deems appropriate in order to reflect the transfer restrictions set forth in
this subparagraph 6(d) and to assure compliance with applicable laws.

         7. TERMINATION OF PARTICIPATION.

            (a) GENERAL STATEMENT. A Non-Employee Director shall cease to be
eligible to execute Stock Conversion Elections under the Plan upon the
occurrence of his Termination of Service for any reason.

            (b) LAPSE OF TRANSFER RESTRICTIONS; DISTRIBUTION. Upon the
occurrence of a Non-Employee Director's Termination of Service, the transfer
restrictions set forth in subparagraph 6(d) shall cease to apply and the
Committee shall direct the Custodian to cause a distribution of all of the whole
shares of Stock in such Non-Employee Director's Account to be made to such
Non-Employee Director (or the person or persons designated as such Non-Employee
Director's beneficiary pursuant to a will or the laws of descent and
distribution) as soon as practicable following such termination. At the time of
distribution of such shares, any fractional share of Stock

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in such Non-Employee Director's Account shall be converted to cash based on the
fair market value of the Stock on the date of distribution and such cash shall
be paid to the Non-Employee Director by the Custodian.

         8. RIGHTS AS STOCKHOLDER. With respect to a Non-Employee Director's
Stock held by the Custodian pursuant to paragraph 6, the Custodian shall
reinvest any cash dividends attributable thereto on behalf of the Non-Employee
Director in additional shares of Stock and shall, in accordance with procedures
adopted by the Custodian, facilitate the Non-Employee Director's voting rights
attributable thereto. Any such Stock purchased with such cash dividends shall be
held by the Custodian in such Non-Employee Director's Account and shall be
subject to the transfer restrictions set forth in subparagraph 6(d).

         9. CHANGES IN STOCK; ADJUSTMENTS. Whenever any change is made in the
outstanding Stock by reason of recapitalizations, reorganizations, mergers,
consolidations, combinations, split-ups, split-offs, spin-offs, exchanges or
other relevant changes in capitalization or distributions to the holders of
Stock, appropriate action will be taken by the Committee in its discretion to
adjust accordingly the shares subject to the Plan and the shares held in
Non-Employee Directors' Accounts. Any such adjustment or determination made by
the Committee shall be conclusive and binding on all parties.

         10. TERM OF THE PLAN. The Plan shall be effective as of January 1,
2001. If not sooner terminated under the provisions of paragraph 11, the Plan
shall terminate upon and no further Stock Conversion Elections shall be made on
or after January 1, 2011.

         11. AMENDMENT OR TERMINATION OF THE PLAN. The Board in its discretion
may terminate the Plan at any time with respect to any shares of Stock for which
Stock Conversion Elections have not theretofore been executed. The Board shall
have the right to alter or amend the Plan or any part thereof from time to time;
provided, however, that no change in the Plan may be made that would impair the
rights of any Non-Employee Director with respect to the shares of Stock in his
Account without the consent of such Non-Employee Director, and provided further,
that the Board may not, without approval of the stockholders of the Company,
amend the Plan to increase the maximum aggregate number of shares that may be
issued under the Plan other than pursuant to paragraph 9.

         12. SECURITIES LAWS. The Company shall not be obligated to issue or
deliver any shares of Stock pursuant to any Stock Conversion Election under the
Plan at any time when the offer, issuance or sale of shares covered by such
Stock Conversion Election has not been registered under the Securities Act of
1933, as amended, or does not comply with such other state, federal or foreign
laws, rules or regulations, or the requirements of any stock exchange upon which
the Stock may then be listed, as the Company or the Committee deems applicable
and, in the opinion of legal counsel for the Company, there is no exemption from
the requirements of such laws, rules, regulations or requirements available for
the offer, issuance and sale of such shares. Further, all Stock acquired
pursuant to the Plan shall be subject to the Company's policies concerning
compliance with securities laws and regulations, as such policies may be amended
from time to time.

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         13. NO RESTRICTION ON CORPORATE ACTION. Nothing contained in the Plan
shall be construed to affect in any way the right or power of the Board or the
stockholders of the Company to make or authorize any adjustment,
recapitalization, reorganization or other change in the Company's or any
Affiliate's capital structure or its business, any merger or consolidation of
the Company or any Affiliate, any issue of debt or equity securities ahead of or
affecting Stock or the rights thereof, the dissolution or liquidation of the
Company or any Affiliate or any sale, lease, exchange or other disposition of
all or any part of its assets or business or any other corporate act or
proceeding.

         14. MISCELLANEOUS PROVISIONS.

             (a) NUMBER AND GENDER. Wherever appropriate herein, words used in
the singular shall be considered to include the plural and words used in the
plural shall be considered to include the singular. The masculine gender, where
appearing in the Plan, shall be deemed to include the feminine gender.

             (b) HEADINGS. The headings and subheadings in the Plan are included
solely for convenience, and if there is any conflict between such headings or
subheadings and the text of the Plan, the text shall control.

             (c) COMPLIANCE WITH APPLICABLE LAWS. The Company's obligation to
offer, issue, sell or deliver Stock under the Plan is at all times subject to
all approvals of and compliance with any governmental authorities (whether
domestic or foreign) required in connection with the authorization, offer,
issuance, sale or delivery of Stock as well as all federal, state, local and
foreign laws. Without limiting the scope of the preceding sentence, and
notwithstanding any other provision in the Plan, the Company shall not be
obligated to offer, issue, sell or deliver Stock under the Plan to any person
who is a citizen or resident of a jurisdiction the laws of which, for reasons of
its public policy, prohibit the Company from taking any such action with respect
to such person.

             (d) SEVERABILITY. If any provision of the Plan shall be held
illegal or invalid for any reason, said illegality or invalidity shall not
affect the remaining provisions hereof; instead, each provision shall be fully
severable and the Plan shall be construed and enforced as if said illegal or
invalid provision had never been included herein.

             (e) GOVERNING LAW. All provisions of the Plan shall be construed in
accordance with the laws of Texas except to the extent preempted by federal law.

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