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                            ARTICLES OF INCORPORATION
                                       OF
                     SOUTHWEST BANCORPORATION OF TEXAS, INC.
                          (Restated as of May 1, 2001)


         The undersigned, a natural person of the age of eighteen years or more,
acting as sole incorporator of a corporation under the provisions of the Texas
Business Corporation Act, adopts the following Articles of Incorporation:

                                   ARTICLE 1.

         The name of the Corporation is Southwest Bancorporation, Inc.

                                   ARTICLE 2.

         The period of duration of the Corporation is perpetual.

                                   ARTICLE 3.

         The purpose for which the Corporation is organized is the transaction
of any or all lawful business.

                                   ARTICLE 4.

         Section 4.1. Authorized Shares. The aggregate number of all classes of
stock which the Corporation has authority to issue is 151,000,000 shares divided
into (A) one class of 150,000,000 shares of Common Stock with a par value of
$1.00 per share, and (B) one class of 1,000,000 shares of Preferred Stock with a
par value of $0.01 per share, which may be divided into and issued in series as
set forth in this Article 4.

         Section 4.2. Authorization of Directors to Determine Certain Rights of
Preferred Stock. The Board of Directors is authorized, from time to time, to
divide the Preferred Stock into series, to designate each series, to fix and
determine separately for each series any one or more of the following relative
rights and preferences, and to issue shares of any series then or previously
designated, fixed and determined:

         (A) the rate of dividend;

         (B) cumulativity of dividends;

         (C) the price at and the terms and conditions on which shares may be
redeemed;

         (D) the amount payable upon shares in event of involuntary liquidation;

         (E) the amount payable upon shares in event of voluntary liquidation;

         (F) sinking fund provisions (if any) for the redemption or purchase of
shares;
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         (G) the terms and conditions on which shares may be converted if the
shares of any series are issued with the privilege of conversion; and

         (H) voting rights (including the number of votes per share, the matters
on which the shares can vote, and the contingencies which make the voting rights
effective).

         Section 4.3. Preferences, Limitations and Relative Rights of All
Classes of Capital Stock.

         (A) General. All shares of Common Stock shall have rights identical to
those of all other such shares. Except as they may vary among series established
pursuant to Section 4.2 of this Article 4, all shares of Preferred Stock shall
have preferences, limitations, and relative rights identical to those of all
other such shares. Except as otherwise expressly provided by law, shares of
Preferred Stock shall have only the preferences and relative rights expressly
stated in this Article 4.

         (B) Dividends.

             (1) Amount; Time. Each series of Preferred Stock at the time
outstanding shall be entitled to receive, when and as declared by the Board of
Directors, out of any funds legally available therefor, dividends at the rate
fixed by the Board of Directors pursuant to Section 4.2 of this Article 4, and
no more.

             (2) Cumulativity. Dividends on Preferred Stock may be cumulative,
noncumulative or partially cumulative as determined by the Board of Directors
pursuant to Section 4.2 of this Article 4. Any such cumulations, of dividends
shall not bear interest.

             (3) Priority over Common Stock: Restriction on Purchases of Common
Stock. No dividend shall be declared or paid on Common Stock, and no Common
Stock shall be purchased by the Corporation, unless (a) dividends cumulated for
all prior dividend periods shall have been declared and paid or shall then be
paid at the same time upon all series of Preferred Stock then outstanding on
which cumulative dividends are authorized by the Board of Directors pursuant to
Section 4.2 of this Article 4, and (b) a dividend for the same period shall have
been paid at the same time upon all series of Preferred Stock then outstanding.

             (4) Parity Among Series. No dividend shall be declared on any
series of Preferred Stock (a) for any dividend period unless all dividends
cumulated for all prior dividend periods shall have been declared or shall then
be declared at the same time upon all series of Preferred Stock then outstanding
on which cumulative dividends are authorized by the Board of Directors pursuant
to Section 4.2 of this Article 4, and (b) unless a dividend for the same period
shall be declared at the same time upon all series of Preferred Stock then
outstanding.

         (C) Liquidation Preference. In the event of dissolution, liquidation,
or winding up of the Corporation (whether voluntary or involuntary), after
payment or provision for payment of debts but before any distribution to the
holders of Common Stock, the holders of each series of Preferred Stock then
outstanding shall be entitled to receive the amount fixed by the Board of
Directors pursuant to Section 4.2 of this Article 4 plus a sum equal to all
cumulated but unpaid dividends (whether or not earned or declared), if any, to
the date fixed for distribution, and no

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more. All remaining assets shall be distributed pro rata among the holders of
Common Stock. If the assets distributable among the holders of Preferred Stock
are insufficient to permit full payment to them, the entire assets shall be
distributed among the holders of the Preferred Stock in proportion to their
respective liquidation preferences. Neither the consolidation, merger, or
reorganization of the Corporation with any other corporation or corporations,
nor the sale of all or substantially all the assets of the Corporation, nor the
purchase or redemption by the Corporation of any of its outstanding shares shall
be deemed to be a dissolution, liquidation, or winding up within the meaning of
this paragraph.

         (D) Redemption.

             (1) Right; Method. All or any part of any one or more series of
Preferred Stock may be redeemed at any time or times at the option of the
Corporation, by resolution of the Board of Directors, in accordance with the
terms and conditions of this Article 4 and those fixed by the Board of Directors
pursuant to Section 4.2 of this Article 4. The Corporation may redeem shares of
any one or more series without redeeming shares of any other series. If less
than all the shares of any series are to be redeemed, the shares of the series
to be redeemed shall be selected ratably or by lot or by any other equitable
method determined by the Board of Directors.

             (2) Notice. Notice shall be given to the holders of shares to be
redeemed, either personally or by mail, not less than twenty nor more than fifty
days before the date fixed for redemption.

             (3) Payment. Holders of redeemed shares shall be paid in cash the
amount fixed by the Board of Directors pursuant to Section 4.2 of this Article 4
plus a sum equal to all cumulated but unpaid dividends (whether or not earned or
declared), if any, to the date fixed for redemption, and no more.

             (4) Provision for Payment. On or before the date fixed for
redemption, the Corporation may provide for payment of a sum sufficient to
redeem the shares called for redemption either (a) by setting aside the sum,
separate from its other funds, in trust for the benefit of the holders of the
shares to be redeemed, or (b) by depositing such sum in a bank or trust company
(either one in Texas having capital and surplus of at least $10,000,000
according to its latest statement of condition, or one anywhere in the United
States duly appointed and acting as transfer agent of the Corporation) as a
trust fund, with irrevocable instructions and authority to the bank or trust
company to give or complete the notice of redemption and to pay to the holders
of the shares to be redeemed, on or after the date fixed for redemption, the
redemption price on surrender of their respective share certificates. The
holders of shares to be redeemed may be evidenced by a list certified by the
Corporation (by its president or a vice president and by its secretary or an
assistant secretary) or by its transfer agent. If the Corporation so provides
for payment, then from and after the date fixed for redemption (a) the shares
shall be deemed to be redeemed, (b) dividends thereon shall cease to accrue, (c)
such setting aside or deposit shall be deemed to constitute full payment for the
shares, (d) the shares shall no longer be deemed to be outstanding, (e) the
holders thereof shall cease to be shareholders with respect to such shares, and
(f) the holders shall have no rights with respect thereto except the right to
receive (without interest) their proportionate shares of the funds so set aside
or deposited upon surrender of their respective certificates, and any right to
convert such shares which may exist.

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Any interest accrued on funds so set aside or deposited shall belong to the
Corporation. If the holders of the shares do not, within six years after such
deposit, claim any amount so deposited for redemption thereof, the bank or trust
company shall upon demand pay over to the Corporation the balance of the funds
so deposited, and the bank or trust company shall thereupon be relieved of all
responsibility to such holders.

             (5) Status of Redeemed Shares. Shares of Preferred Stock which are
redeemed shall be cancelled and shall be restored to the status of authorized
but unissued shares.

         (E) Purchase. Except as specified in Section 4.3(B)(3) of this Article
4, nothing herein shall limit the right of the Corporation to purchase any of
its outstanding shares in accordance with law, by public or private transaction.

         (F) Voting. Except as fixed by the Board of Directors pursuant to
Section 4.2 of this Article 4, and except as otherwise expressly provided by
law, all voting power shall be in the Common Stock and none in the Preferred
Stock. Except as fixed by the Board of Directors pursuant to Section 4.2 of this
Article 4, and except as otherwise expressly provided by law, where one or more
series of Preferred Stock have voting power, all series of Preferred Stock
having such power shall not be entitled to vote as a separate class.

         (G) Denial of Preemptive Rights and Cumulative Voting. No shareholder
or any other person shall have any preemptive right whatsoever, and cumulative
voting shall not be permitted.

                                   ARTICLE 5.

         The Corporation will not commence business until it has received for
the issuance of its shares consideration of the value of at least $1,000.

                                   ARTICLE 6.

         Without necessity for action by its shareholders, the Corporation may
purchase, directly or indirectly, its own shares to the extent of the aggregate
of unrestricted capital surplus available therefor and unrestricted reduction
surplus available therefor.

                                   ARTICLE 7.

         Section 7.1. Voting Requirement. Notwithstanding any provision of the
Texas Business Corporation Act which requires the vote or concurrence of the
holders of more than a majority of the shares of the Corporation entitled to
vote to take an action, the vote or concurrence of the holders of a majority of
the shares of the Corporation entitled to vote shall be sufficient to take such
action.

         Section 7.2. Quorum Requirement. The holders of at least a majority of
the shares of the Corporation entitled to vote, represented in person or by
proxy, shall constitute a quorum at any meeting of shareholders of the
Corporation.

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         Section 7.3. Interested Transactions. No contract or other transaction
between the Corporation and one or more of its directors, officers or
securityholders or between the Corporation and another corporation, partnership,
joint venture, trust or other enterprise of which one or more of the
Corporation's directors, officers or securityholders are members, officers,
securityholders, directors or employees or in which they are otherwise
interested, directly or indirectly, shall be invalid solely because of such
relationship, or solely because such director, officer or securityholder is
present at or participates in the meeting of the Board of Directors or committee
thereof which authorizes the contract or other transaction, or solely because
his or their votes are counted for such purpose, if (A) the material facts as to
his relationship or interest and as to the contract or other transaction are
known or disclosed to the Board of Directors or committee thereof, and such
board or committee in good faith authorizes the contract or other transaction by
the affirmative vote of a majority of the disinterested directors even though
the disinterested directors be less than a quorum, or (B) the material facts as
to his relationship or interest and as to the contract or other transaction are
known or disclosed to the shareholders entitled to vote thereon, and the
contract or other transaction is approved in good faith by vote of the
shareholders, or (C) the contract or other transaction is fair as to the
Corporation as of the time it is entered into.

         Section 7.4. Special Meetings of Shareholders. The shareholders of the
Corporation shall have the power to call a special meeting of the shareholders
of the Corporation only upon a written request delivered to the Corporation
signed by holders of at least one-third of the outstanding shares entitled to
vote at the proposed special meeting.

         Section 7.5. Amendment of Bylaws. The power to amend the Bylaws of the
Corporation shall be vested exclusively in the Board of Directors.

                                   ARTICLE 8.

         Section 8.1. Indemnification. As permitted by Section G of Article
2.02-1 of the Texas Business Corporation Act as in effect on the date of the
filing of these Articles of Incorporation with the Secretary of State of the
State of Texas ("Indemnification Article"), the Corporation hereby:

         (A) makes mandatory the indemnification permitted under Section B of
the Indemnification Article as contemplated by Section G thereof;

         (B) makes mandatory its payment or reimbursement of the reasonable
expenses incurred by a director who was, is, or is threatened to be made a named
defendant or respondent in a proceeding upon such director's compliance with the
requirements of Section K of the Indemnification Article; and

         (C) extends the mandatory indemnification referred to in Section 8.1
(A) above and the mandatory payment or reimbursement of expenses referred to in
Section 8.1 (B) above (i) to all officers of the Corporation and (H) to all
persons who are or were serving at the request of the Corporation as a director,
officer, partner or trustee of another foreign or domestic corporation,
partnership, joint venture, trust or employee benefit plan, to the same extent
that the Corporation is obligated to indemnify and pay or reimburse expenses to
directors.

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         Section 8.2. Insurance. The Corporation may purchase and maintain
insurance or another arrangement on behalf of any person who is or was a
director, officer, employee, or agent of the Corporation, or who is or was
serving at the request of the Corporation as a director, officer, partner,
venturer, proprietor, trustee, employee, agent, or similar functionary of
another foreign or domestic corporation, partnership, joint venture, sole
proprietorship, trust, employee benefit plan, or other enterprise, against any
liability asserted against him and incurred by him in such a capacity or arising
out of his status as such a person, whether or not the Corporation would have
the power to indemnify him against that liability under the Indemnification
Article.

         Section 8.3. Non-Exclusivity. The provisions of Sections 8.1 and 8.2 of
this Article 8 shall not be deemed exclusive of any other rights to which any
such director, officer or other person may be entitled under any other
agreement, pursuant to a vote of directors or any committee thereof or a vote of
shareholders, as a matter of law or otherwise, either as to action in his
official capacity or as to action in another capacity while holding such office,
and shall continue as to a person who has ceased to be a director or officer and
shall inure to the benefit of the heirs, executors and administrators of such a
person. No person shall be entitled to indemnification pursuant to this Article
8 in relation to any matter as to which indemnification shall not be permitted
by law.

                                   ARTICLE 9.

         In performing his duties, a director of the Corporation shall be
entitled to rely on information, opinions, reports or statements, including
financial statements and other financial data, in each case prepared or
presented by (A) one or more officers or employees of the Corporation whom the
director reasonably believes to be reliable and competent in the matters
presented, (B) counsel, public accountants or other persons as to matters which
the director reasonably believes to be within such person's professional or
expert competence, or (C) a committee of the Board of Directors upon which he
does not serve, duly designated in accordance with a provision of the bylaws, as
to matters within its designated authority, which committee the director deems
to merit confidence, but he shall not be considered to be acting in good faith
if he has knowledge concerning the matter in question that would cause such
reliance to be unwarranted. A person who so performs his duties shall have no
liability to the Corporation (whether asserted directly or derivatively) by
reason of being or having been a director of the Corporation.

         No director of the Corporation shall be liable to the Corporation or
its stockholders for monetary damages for an act or omission in the director's
capacity as a director, except to the extent that the foregoing exemption from
liability is not permitted under the applicable provision of the Texas
Miscellaneous Corporation Laws Act (or any successor or replacement statute) as
the same now exists or may hereafter be amended.

         Any repeal or modification of the foregoing paragraph shall not
adversely affect any right or protection of a director of the Corporation
existing at the time of such repeal or modification.

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                                  ARTICLE 10.

         The address of the initial registered office of the Corporation is 4295
San Felipe, Houston, Texas 77027, and the name of the initial registered agent
of the Corporation at such address is Walter E. Johnson.

                                  ARTICLE 11.

         The initial Board of Directors shall consist of six (6) members who
shall serve as directors until the first annual meeting of shareholders or until
their successors shall have been elected and qualified, and whose names and
addresses are as follows:

NAME                                    ADDRESS
----                                    -------
Walter E. Johnson                       4295 San Felipe
                                        Houston, Texas 77027

Paul B. Murphy, Jr.                     4295 San Felipe
                                        Houston, Texas 77027

John W. Johnson                         4295 San Felipe
                                        Houston, Texas 77027

Beth R. Morian                          4295 San Felipe
                                        Houston, Texas 77027

Michael T. Willis                       4295 San Felipe
                                        Houston, Texas 77027

Ernest H. Cockrell                      4295 San Felipe
                                        Houston, Texas 77027

                                   ARTICLE 12.

         The name and address of the incorporator of the Corporation is as
follows:

NAME                                    ADDRESS
----                                    -------
Duncan W. Stewart                       711 Louisiana, Suite 2900
                                        Houston, Texas 77002

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         IN WITNESS WHEREOF, I have hereunto set my hand this 27th day of March,
1996.


                                     /s/ DUNCAN W. STEWART
                                         Duncan W. Stewart

Sworn to on March 27, 1996, by the above named incorporator.

                                     /s/ MARY ANN MOUSER
                                     Notary Public in and for the State of Texas


                                     Print Name: Mary Ann Mouser
                                     My Commission Expires: 2/6/97

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