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                                                                     EXHIBIT 4.8
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                              Fourth Amendment to
                            Southwest Bank of Texas
                              401(k) Savings Plan
                (As Amended and Restated as of January 1, 1994)



     WHEREAS, Southwest Bank of Texas, N.A., a corporation organized under the
laws of the State of Texas ("Southwest Bank"), maintains the Southwest Bank of
Texas 401(k) Savings Plan, as amended and restated as of January 1, 1994 (the
"Plan") for the benefit of its eligible employees and their beneficiaries; and

     WHEREAS, the Plan provides in Section 12.02 thereof that Southwest Bank has
the right at any time and from time to time to amend the Plan; and

     WHEREAS, Southwest Bank desires to amend the Plan;

     NOW, THEREFORE, the Plan shall be amended as follows, effective as of May
1, 1997, except as otherwise provided herein:

     1. The following new Section 1.13(A) shall be added to the Plan:

        "1.13(A)  'Employer Stock' means the common stock, par value $1.00 per
        share, of Southwest Bancorporation of Texas, Inc."

     2. Section 1.21 of the Plan shall be amended by deleting the word
        "Accounting" each place it appears in such section and substituting
        therefor the word "Valuation."

     3  The following new section 1.31(A) shall be added to the Plan:

        "1.31(A)   'Valuation Date' means each and every day of the Plan Year
        on which the New York Stock Exchange is open for business."

     4. The second paragraph of Section 3.09(a)(2) of the Plan which begins with
        "Special Allocation Provisions for Employer Matching Contributions
        Account and Qualified Matching Contributions Account." shall be deleted.

     5. The second sentence of Section 3.10 of the Plan shall be deleted and the
        following shall be substituted therefor:

        "Forfeitures not used to pay expenses shall be allocated under the
        Plan as of the last day of a Plan Year to Participants in the Plan
        pursuant to Section 3.11(c)."

     6. The second sentence of Section 3.11(c) of the Plan shall be deleted.
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     7.  The second sentence of Section 5.03 of the Plan shall be deleted.

     8.  The third sentence of Section 6.01 of the Plan shall be deleted and the
         following shall be substituted therefor:

         "A 'Distribution Date' under this Article VI, unless otherwise
         specified within the Plan, shall be the date which is as soon as
         administratively feasible after the date of Separation from Service or
         any later date as directed by the Participant; provided, however, that
         the portion of a Participant's Accrued Benefit credited for the periods
         prior to January 1, 1994 shall not be distributed prior to the
         expiration of the seven-day period that begins the day after the
         information required to be furnished pursuant to Section 6.05 has been
         furnished to the Participant."

     9.  The first sentence of Section 6.02 of the Plan shall be deleted and the
         following shall be substituted therefor:

         "A Participant's Accrued Benefit, credited for the periods beginning
         after December 31, 1993, shall be distributed only in a cash lump sum
         except that a Participant (or his designated Beneficiary, surviving
         spouse or legal representative in the case of a deceased Participant)
         may elect to have the portion of the Participant's Accounts invested in
         Employer Stock distributed (or transferred pursuant to Section 6.09) in
         full shares of Employer Stock with any balance of the Participant's
         Accounts invested in Employer Stock attributable to fractional shares
         to be paid or transferred in cash."

     10. The second sentence of Section 6.03 of the Plan shall be deleted and
         the following shall be substituted therefor:

         "A Participant's Account Balance is eligible for distribution as soon
         as administratively feasible following the date of the Participant's
         Separation from Service."

     11. The last sentence in the first paragraph of Section 6.07 of the Plan
         shall be deleted.

     12. Section 8.10 of the Plan shall be deleted and the following new Section
         8.10 shall be substituted therefor:

         "8.10  PARTICIPANT DIRECTION OF INVESTMENT.  A Participant may elect
         to have amounts credited to his Account invested in the investment
         funds made available by the Administrative Committee.

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               (a) Each Participant shall designate, in accordance with the
          procedures established from time to time by the Administrative
          Committee, the manner in which the amounts allocated to each of his
          Accounts shall be invested from among the investment funds made
          available from time to time by the Administrative Committee.  With
          respect to each of a Participant's Accounts, such Participant may
          designate one of such investment funds for all the amounts allocated
          to such Account or he may split the investment of the amounts
          allocated to such Account between such investment funds in such
          increments as the Administrative Committee may prescribe.  If a
          Participant fails to make a designation, then his Accounts shall be
          invested in the investment fund or funds designated by the
          Administrative Committee from time to time in a uniform and
          nondiscriminatory manner.

               (b) A Participant may change his investment designation for
          future contributions to be allocated to any one or all of his
          Accounts.  Any such change shall be made in accordance with the
          procedures established by the Administrative Committee, and the
          frequency of such changes may be limited by the Administrative
          Committee.

               (c) A Participant may elect to convert his investment designation
          with respect to the amounts already allocated to one or more of his
          Accounts.  Any such conversion shall be made in accordance with the
          procedures established by the Administrative Committee, and the
          frequency of such conversions may be limited by the Administrative
          Committee.

               (d) In the event that the Employer elects to make a Discretionary
          Contribution to the Plan, the Employer shall have the right to
          designate the investment fund or funds in which such Discretionary
          Contribution shall be invested and a Participant may not change the
          investment designation for such Discretionary Contribution unless and
          until permitted by the Administrative Committee.  If the Employer
          elects to make a Discretionary Contribution to the Plan and does not
          designate an investment fund or funds in which such Discretionary
          Contribution shall be invested, such amounts shall be subject to the
          provisions of Section 8.10(a) above."

     13. The second sentence in Section 9.10 of the Plan shall be deleted and
         the following shall be substituted therefor:

          "For purposes of a distribution under the Plan, the value of a
          Participant's Account balance is its value as of the Valuation Date

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          coincident with or immediately preceding the date of the
          distribution."

     14. The third paragraph of Section 9.11 of the Plan which begins with
         "Special Provisions for Employer Matching Contribution Account and 
         Qualified Matching Contributions Account" shall be deleted.

     15. The last sentence of Section 10.03 of the Plan shall be deleted.

     16. Section 10.08 of the Plan shall be deleted and the following new 
         section 10.08 shall be substituted therefor:

         "10.08 DISTRIBUTION OF CASH OR PROPERTY. The Trustee may make
         distribution under the Plan in cash or property, or partly in each, at
         its fair market value as determined by the Trustee. For purposes of a
         distribution to a Participant or to a Participant's designated
         Beneficiary or surviving spouse, "property" includes a nontransferable
         annuity contract, provided the contract satisfies the requirements of
         the Plan."

     17. Section 10.14 of the Plan shall be deleted and the following new 
         Section 10.14 shall be substituted therefor:

         "10.14 VALUATION OF TRUST. The Trustee shall value the Trust Fund as of
         each Accounting Date to determine the fair market value of each
         Participant's Accounts. The Trustee may also value the Trust Fund on
         such other interim Valuation Dates as the Trustee deems appropriate."

     18. As amended hereby, the Plan is specifically ratified and reaffirmed.

     Executed this 18th day of March, 1997.

                                        SOUTHWEST BANK OF TEXAS, N.A.


                                        By:   David C. Farries
                                           -------------------------------
                                            Executive Vice President

Attest:



  Cassandra Sweet
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