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

         1. STOCK CONVERSION ELECTION. I understand that, in lieu of receiving
the cash compensation payable to me in exchange for my 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 Southwest Bancorporation of Texas,
Inc. (the "Company") and/or of the Board of Directors of Southwest Bank of Texas
National Association (the "Bank"), during the 200 calendar year (my "Eligible
Compensation"), I may elect, pursuant to the Southwest Bancorporation of Texas,
Inc. Non-Employee Director Stock Plan (the "Plan"), to convert such Eligible
Compensation into nonforfeitable shares of the common stock of the Company, par
value $1.00 (the "Stock"), to be held in a custodial account ("Account") and
subject to the transfer restrictions set forth in the Plan until such time as I
terminate my service as a member of the Board of Directors of the Company and/or
of the Bank. I also understand that the number of shares of Stock to be held in
my Account in lieu of the receipt of my Eligible Compensation will be determined
in accordance with the terms of the Plan and will have a fair market value equal
to such Eligible Compensation.

         2. RIGHTS AS STOCKHOLDER. I understand that the custodian selected by
the committee administering the Plan to maintain my Account (the "Custodian")
will, on my behalf, reinvest any cash dividends attributable to the shares of
Stock in my Account in additional shares of Stock and, in accordance with
procedures established by the Custodian, facilitate my voting rights
attributable to the shares of Stock in my Account. I also understand that any
such Stock purchased with such cash dividends will be subject to the same
transfer restrictions as applied to the underlying Stock to which it is
attributable.

         3. DISTRIBUTION. I understand that following my termination of service
as a member of the Board of Directors of the Company and/or of the Bank, I will
receive a distribution of all the shares of Stock held in my Account (any
fractional share will be paid in cash).

         4. PLAN DOCUMENT; PROSPECTUS. I acknowledge receipt of a copy of the
Plan and understand that the shares of Stock held in my Account, and the
community property interest of my spouse, if any, in such shares will be subject
to all of the terms and provisions of the Plan, including amendments thereto. I
also acknowledge receipt of a copy of the Plan's prospectus.

         Based upon the foregoing, I hereby irrevocably elect to convert my
Eligible Compensation into nonforfeitable shares of Stock for the designated
calendar year as provided above and in accordance with the terms of the Plan.



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                                                SIGNATURE OF DIRECTOR


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                                                PRINTED NAME

RECEIVED BY THE COMPANY


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