S-3/A

As filed with the Securities and Exchange Commission on May 18, 2005

Registration No. 333-124502

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

PRE-EFFECTIVE AMENDMENT NO. 1
FORM S-3
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

Southwest Bancorp, Inc.
(Exact name of registrant as specified in its charter)

Oklahoma	73-1136584
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification Number)

608 South Main Street
Stillwater, Oklahoma 74074
405.372.2230
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Rick Green
President and Chief Executive Officer
Southwest Bancorp, Inc.
608 South Main Street
Stillwater, Oklahoma 74074
405.372.2230
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

James I. Lundy, III, Esquire
1700 Pennsylvania Avenue, NW
Suite 400
Washington, D.C. 20006
202.349.7130
202.318.4623 (fax) Noel M. Gruber, Esquire
Kennedy & Baris, L.L.P.
4701 Sangamore Road, Suite P-15
Bethesda, Maryland 20816
301.229.3400
301.229.2443(fax) James L. Nouss, Jr., Esquire
Harold R. Burroughs, Esquire
Bryan Cave LLP
211 North Broadway, Suite 3600
St. Louis, Missouri 63102
314.259.2000
314.552.8706 (fax)

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this Registration Statement.

If any of the securities being registered on this form are to be offered pursuant to dividend or interest reinvestment plans, please check the following box.     

If the only securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under
the Securities Act of 1933, other than securities offered in connection with dividend or interest reinvestment plans, check the
following box.     

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please
check the following box and list the Securities Act registration statement number of the earlier effective registration statement for
the same offering.      ____________

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.     ____________

If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box.     

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Amount to be Registered	Proposed Maximum Offering Price per Share(1)	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(1)
Common stock, $1.00 par value(2)	2,415,000	$18.46	$44,580,900	$5,185.00

(1) Estimated solely for the purpose of computing the registration fee pursuant to Rule 457(c) under the Securities Act, based on the average of the high and low prices of the registrant’s common stock as reported on the Nasdaq National Market on May 16, 2005. Fee includes $4,794.00 paid with initial filing.

(2) Includes the attendant preferred stock purchase rights pursuant to the rights agreement dated as of April 22, 1999, between the registrant and Harris Trust and Savings Bank, as rights agent.

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

SUBJECT TO COMPLETION, DATED MAY 18, 2005

PROSPECTUS

2,100,000 Shares

Common Stock

We are offering 2,100,000 shares of our common stock.

Our common stock is traded on the Nasdaq National Market under the symbol “OKSB.” The last reported sale price of our common stock on the Nasdaq National Market on May 16, 2005 was $18.58 per share.

Investing in our common stock involves risks. See “Risk Factors,” beginning on page 8.

	Per Share	Total
Public offering price	$	$
Underwriting discount	$	$
Proceeds to us (before expenses)	$	$

This is a firm commitment underwriting. We have granted the underwriters a 30-day option to purchase up to an additional 315,000 shares of common stock at the same price to cover over-allotments, if any.

These securities are not deposits, savings accounts, or other obligations of any bank or savings association and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

The underwriters expect to deliver the common stock to purchasers on or about      , 2005, subject to customary closing conditions.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Stifel, Nicolaus & Company

                 Incorporated

Edward Jones

Friedman, Billings, Ramsey & Co., Inc.

Keefe, Bruyette & Woods

SunTrust Robinson Humphrey

                , 2005

The information in this prospectus is not complete and may be changed. We may not sell these securities until the Securities and Exchange Commission declares our registration statement effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PROSPECTUS SUMMARY

This summary highlights information that is contained elsewhere in, or incorporated by reference into this prospectus. This summary does not contain all of the information that you should consider before investing in our common stock. You should read the entire prospectus as well as the documents incorporated by reference into this prospectus before making an investment decision. Except as otherwise indicated by the context, references in the prospectus to “we,” “our,” or “us” are to the combined business of Southwest Bancorp, Inc. From time to time we use the term “Southwest” to refer to Southwest Bancorp, Inc., the term “Stillwater National” to refer to Stillwater National Bank and Trust Company, and the term “SNB Wichita” to refer to SNB Bank of Wichita. Unless otherwise indicated, the information contained in this prospectus assumes that the underwriters will not exercise their option to purchase additional shares to cover over-allotments.

Southwest Bancorp, Inc.

Southwest Bancorp, Inc. is the financial holding company for Stillwater National Bank and Trust Company, SNB Bank of Wichita, and two consulting subsidiaries, Business Consulting Group, Inc. and Healthcare Strategic Support, Inc. We offer commercial and consumer lending, deposit, and investment services, and specialized cash management, consulting, and other financial services from twelve full-service offices in Oklahoma City, Tulsa, Chickasha, and Stillwater, Oklahoma; Dallas, Austin, and San Antonio, Texas; and Wichita, Kansas; loan production offices in Kansas City, Kansas, and on the campuses of the University of Oklahoma Health Sciences Center and Oklahoma State University-Tulsa; a marketing presence in the Student Union at Oklahoma State University-Stillwater; and on the Internet, through SNB DirectBanker^®. We were organized in 1981 as the holding company for Stillwater National, which was chartered in 1894.

Historical Growth and Performance

At March 31, 2005, we had total assets of $2.0 billion, deposits of $1.6 billion, and shareholders’ equity of $129.7 million. We became a public company in late 1993 with assets of approximately $434.0 million.

Over the five years ending on December 31, 2004, we increased our:

• Loans at an average annual rate of 14.0% per year;

• Assets at 11.5% per year;

• Net income at 16.1% per year;

• Book value per share at 13.6%; and

• Diluted earnings per share at 15.3% per year.

Our growth to date has been accomplished internally, without mergers or acquisitions, through the establishment of new offices in markets that we believed would allow us to capitalize on our strengths.

The following table highlights our recent growth and performance.

	As of and for the Three Months Ended March 31,						As of and for the Years Ended December 31,
	2005			2004			2004			2003			2002			2001			2000
	(Dollars in thousands, except per share data)
Net income	$	5,386		$	4,202		$	18,629		$	14,892		$	13,419		$	11,752		$	10,205
Diluted earnings per share		0.43			0.34			1.48			1.22			1.11			1.00			0.88
Total assets		1,994,569			1,695,241			1,913,787			1,581,564			1,351,279			1,217,796			1,204,940
Total loans (including loans held for sale)		1,673,778			1,419,282			1,623,875			1,308,836			1,101,112			931,046			912,550
Total deposits		1,628,934			1,291,626			1,500,058			1,204,125			1,021,757			904,796			945,102
Total shareholders’ equity		129,734			114,906			125,984			109,935			96,372			85,125			73,239
Book value per share		10.64			9.55			10.41			9.20			8.35			7.47			6.44
Net interest margin		4.42	%		3.96	%		4.16	%		3.80	%		3.75	%		3.53	%		3.57	%
Efficiency ratio		48.94			56.11			51.31			54.95			56.92			59.62			60.93
Return on average assets		1.08			1.02			1.03			0.99			1.05			0.96			0.87
Return on average equity		16.73			14.99			15.80			14.59			14.94			14.87			14.89

All per share information has been restated to reflect the three-for-two stock split effected in the form of a stock dividend paid August 29, 2001, and the two-for-one stock split effected in the form of a stock dividend paid August 29, 2003.

Reflects the retroactive reclassification of the allowance related to unfunded loan commitments from the allowance for loan losses to a reserve for unfunded loan commitments, which is now shown as a liability on the statement of financial condition.

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Strategic Focus

Our banking philosophy is to provide a high level of customer service, a wide range of financial services, and products responsive to customer needs. We focus on serving healthcare and health professionals, businesses and their managers and owners, and commercial and commercial real estate borrowers. Our banking philosophy has led to the development of a line of deposit, lending, and other financial products that respond to professional and commercial customer needs for speed, efficiency, and information, and complement our more traditional banking products. Our specialized financial services include integrated document imaging and cash management services designed to help our customers in the healthcare industry and other record-intensive enterprises operate more efficiently. We seek to build close relationships with businesses, professionals and their principals and to service their banking needs throughout their business development and professional lives.

We have established two management consulting subsidiaries that complement our commercial services and help to differentiate us from our competitors. Healthcare Strategic Support, Inc. provides management consulting services for physicians, hospitals, and healthcare groups. Business Consulting Group, Inc. provides marketing, strategic, logistics, and operations consulting for small and large commercial enterprises. We believe that our consulting subsidiaries help us to gain new banking customers and expand our relationship with existing customers.

Growth Strategy

We use three business models to take advantage of selected growth opportunities in markets with characteristics that we believe will allow us to capitalize on our strengths.

Niche Banking Model.     Our traditional areas of expertise focus on the special financial needs of healthcare and health professionals, businesses and their managers and owners, and commercial and commercial real estate borrowers. We developed our niche banking model in connection with our expansion into Oklahoma City in 1982 and Tulsa in 1985. Since 2002, we have used this model to expand into Dallas, Austin, and San Antonio, Texas; and Wichita and Kansas City, Kansas. At March 31, 2005, our five Texas and two Kansas offices accounted for $399.3 million in loans, excluding loan participations sold to other financial institutions.

We plan to open additional offices under our niche banking model using the following, tested approach:

• Identify markets for expansion based upon geographic concentrations of customers in our traditional areas of expertise: healthcare and health professionals, businesses and their managers and owners, and commercial and commercial real estate lending.

• Hire one or more experienced senior lenders with knowledge of the market. Specialists in cash management and other services based at other locations provide sales and support assistance. Staff is added as needed to generate and support business.

• Establish an attractive “private banking” style loan production office.

• Convert the loan production office into a full service banking office of Stillwater National or SNB Wichita after we determine that the office is likely to be successful based upon its business base, loans in process, potential deposit growth from its customers and acceptance by the community.

In our experience, it takes approximately fourteen months from establishment for a niche banking office to become profitable on a monthly basis, and twenty-seven total months to recover our initial investment.

Community Banking Model.     We began as a community bank in 1894. We continue to operate our community banking model in Stillwater, our home market, and Chickasha, Oklahoma. In those markets, we are a full-service community bank emphasizing both commercial and consumer lending. We have more than 60% of the banking deposits in the Stillwater/Payne County market. We intend to employ this community banking model to expand in favorable markets that may not meet our market criteria for our niche banking model but that we believe will support our overall growth strategy.

Secondary Market Model.     We have a long history of student and residential mortgage lending. Our secondary market activities have contributed significantly to our total loans, assets, revenues, and net income. Secondary market loan volumes and profits may vary significantly from period to period. We offer both government guaranteed and privately guaranteed student loans. During fiscal year 2004, we were one of the top 40

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student lenders in the nation by dollar volume of new guarantees originated, according to the Department of Education. We market student lending programs directly to financial aid directors at post-secondary schools. Our residential mortgage lending activities focus on one-to-four family residential borrowers in our banking markets.

We plan to continue the expansion of our secondary market activities, in particular student lending, due to the attractive nature of the business, including its government guarantees, low cost of dedicated funding, and low incremental overhead needed to maintain a larger portfolio. Our expansion in this area may slow, however, as our niche banking and community banking models continue to grow and require us to reallocate capital to those businesses.

We anticipate that part of our planned banking expansion may be accomplished through establishment of new offices as well as through acquisitions of existing banks. Our growth to date has been accomplished without banking acquisitions. We have considered acquisitions of other financial institutions and other companies, from time to time, and intend to pursue possible bank acquisitions in the future, although we do not have any specific agreements or understandings for any such acquisition at present. See “Use of Proceeds” on page 14.

Centralized Support and Control

Our support and control functions and our credit policies, including loan review, funds management, accounting, audit, compliance, and human resources, are uniform and centralized, but we have established their structure to allow prompt and flexible decision making. We offer products that are technology based, or that otherwise are more efficiently offered centrally, through our home office. These include products that are marketed through the regional offices, such as Southwest’s internet banking product for commercial and retail customers (SNB DirectBanker^®), commercial information, and item processing services (Business Mail Processing), and products marketed and managed directly by central staff, such as cash dispensing machines.

We plan to use offering proceeds to support growth.

We intend to use the net proceeds of the offering:

• To support continued expansion using our niche banking model in our current markets and in carefully selected new markets;

• To support funding and asset growth using our community banking model in favorable markets;

• To support higher levels of secondary market lending to make full use of capital while our core banking assets grow; and

• For general corporate purposes, including investment in Stillwater National or SNB Wichita.

Our principal executive offices are located at 608 South Main Street, Stillwater, Oklahoma 74074. Our telephone number is (405) 372-2230.

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THE OFFERING

Company	Southwest Bancorp, Inc.
Common stock offered by:
Southwest Bancorp, Inc. (1)	2,100,000 shares
Offering price per share	$
Shares of common stock outstanding after the offering (1)(2)	13,605,205
Net proceeds to us (1)(3)	We estimate that the net proceeds to us from the sale of 2,100,000 shares of our common stock in this offering will be approximately $36.2 million, after deducting the underwriting discount and the offering expenses payable by us.
Use of proceeds	We intend to use our net proceeds to support continued expansion in current or new markets, to support higher levels of secondary market lending, and for general corporate purposes, including investment in Stillwater National and SNB Wichita. There are no definitive plans for any acquisitions. Pending these uses, we may invest net proceeds in marketable investment securities or short-term, interest-bearing assets. See “Use of Proceeds” on page 14.
Risk factors	See “Risk Factors” beginning on page 8 and other information included or incorporated by reference in this prospectus for a discussion of factors that you should consider before investing in our common stock.
Dividends on common stock	Our quarterly dividends declared for the year ended December 31, 2004, totaled $0.28 per share. On April 1, 2005, we paid a dividend of $0.075 per share to shareholders of record on March 17, 2005. See “Price Range of Common Stock and Dividends” on page 15.
Nasdaq National Market symbol	“OKSB”

(1) Assumes that the underwriters will not exercise their option to purchase up to an additional 315,000 shares of our common stock to cover over-allotments, if any. See “Underwriting” beginning on page 25.

(2) The number of shares outstanding after the offering is based on the number of shares outstanding as of May 13, 2005, less the 689,796 shares repurchased or to be repurchased by us pursuant to a selling shareholder agreement, and plus the number of shares of common stock offered by us. If the underwriters exercise their option in full, 13,920,205 shares of our common stock will be outstanding immediately after the offering. The number of shares of our common stock outstanding after the offering shown above excludes a total of:

• 1,035,982 shares that we may issue upon the exercise of stock options outstanding as of March 31, 2005, at a weighted average exercise price of $10.93 per share; and

• 485,427 additional shares that we may issue under the Southwest Bancorp 1999 Stock Option Plan, as amended, as of March 31, 2005. See “Recent Developments” on page 5.

(3) Based upon an assumed public offering price of $18.58 per share, the last reported sale price for our common stock on the Nasdaq National Market on May 16, 2005.

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RECENT DEVELOPMENTS

Planned Redemption of Subordinated Debentures

We previously announced that we intend to redeem all of the $25.8 million of 9.30% Junior Subordinated Deferrable Interest Debentures due 2027, effective June 24, 2005. The redemption of the subordinated debentures will be concurrent with the redemption of the 9.30% Cumulative Trust Preferred Securities issued by Southwest’s subsidiary, SBI Capital Trust, which holds all of these subordinated debentures. These trust preferred securities were originally issued in June 1997, and are listed on the Nasdaq National Market under the symbol “OKSBO.” We are funding this redemption with proceeds from our issuance of trust preferred securities and subordinated debentures in October 2003. We delayed this redemption pending issuance of federal regulatory capital rules for trust preferred securities, which occurred earlier this year. We expect that the write-off of unamortized costs in connection with the redemption will reduce net income in the second quarter of 2005 by approximately $593,000. We believe that the redemption will benefit net income in future periods as the subordinated debentures are replaced with funds that bear lower interest rates. See “Capitalization” on page 16.

Purchase of Common Stock

On May 13, 2005, we entered into a Selling Shareholder Agreement with Betty B. Kerns, the Joyce P. Berry Revocable Trust, the Joe M. Berry Trust, the Berry Charitable Remainder Trust, and BKP, L.L.C. This agreement provides for the sale by these selling shareholders of a total of 689,796 shares of our common stock at a price of $18.00 per share and for the cancellation of all of the outstanding stock options previously granted to Ms. Kerns in return for a payment equal to the excess of $18.00 over the exercise price per share of options for the 10,826 shares that were exercisable by Ms. Kerns on May 13, 2005. The total consideration payable by us to the selling shareholders under the agreement is approximately $12.5 million. The shares to be repurchased under the agreement represent approximately 5.65% of the 12.2 million shares outstanding on May 13, 2005.

Approximately 680,000 of the shares subject to the agreement were held by entities related to the estate of Joyce P. Berry, who died earlier this year. The selling shareholders have indicated that a significant portion of the proceeds from their sale will be used for payment of estate related taxes. Ms. Kerns is a management official or trustee of, or has a financial interest in, each of the other selling shareholders. Ms. Kerns resigned from our board of directors on May 13, 2005.

On May 16, 2005, Southwest acquired 669,302 shares of common stock under the agreement, and all of the stock options previously granted to Ms. Kerns were cancelled. We expect to acquire the remaining 20,494 shares under the agreement on or before May 20, 2005.

Southwest, Stillwater National, and SNB Wichita will remain well-capitalized for regulatory purposes after the repurchase of shares and cancellation of options required by the agreement.

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SUMMARY CONSOLIDATED FINANCIAL DATA

The following table presents our summary consolidated financial data for each of the five years in the period ended December 31, 2004 and for the quarterly periods ending March 31, 2005 and 2004. The summary consolidated financial data should be read in conjunction with our “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and consolidated financial statements, including the accompanying notes, included in our Annual Report on Form 10-K for the year ended December 31, 2004, and our Quarterly Report on Form 10-Q for the quarter ended March 31, 2005, which are incorporated by reference in this prospectus. The financial data as of and for each of the five years ended December 31, 2000 through 2004 are derived from our audited financial statements. The financial data as of and for the quarterly periods ending March 31, 2005 and 2004 are unaudited, but include all adjustments that we believe are necessary for a fair presentation. Past performance is not necessarily predictive of future performance, and prior results should not be considered indicative of the results to be expected for any future period.

	As of and for the Three Months Ended March 31,						As of and for the Years Ended December 31,
	2005			2004			2004			2003			2002			2001			2000
	(Dollars in thousands, except per share data)
Operations Data:
Interest income	$	31,946		$	22,758		$	104,723		$	84,079		$	76,495		$	90,400		$	97,274
Interest expense		10,854			7,140			32,246			28,611			30,678			48,939			57,227
Net interest income		21,092			15,618			72,477			55,468			45,817			41,461			40,047
Provision for loan losses		4,309			1,649			12,982			8,522			5,443			4,000			3,550
Other income		3,720			3,118			14,085			14,500			12,718			10,813			8,561
Other expense		12,144			10,512			44,412			38,448			33,319			31,165			29,615
Income before taxes		8,359			6,575			29,168			22,998			19,773			17,109			15,443
Taxes on income		2,973			2,373			10,539			8,106			6,354			5,357			5,238
Net income	$	5,386		$	4,202		$	18,629		$	14,892		$	13,419		$	11,752		$	10,205
Per Share Data: (1)
Basic earnings per share	$	0.44		$	0.35		$	1.54		$	1.26		$	1.17		$	1.03		$	0.89
Diluted earnings per share		0.43			0.34			1.48			1.22			1.11			1.00			0.88
Cash dividends declared per share		0.075			0.07			0.28			0.25			0.22			0.16			0.15
Book value per share (2)		10.64			9.55			10.41			9.20			8.35			7.47			6.44
Tangible book value per share		10.62			9.53			10.39			9.18			8.33			7.45			6.42
Weighted average shares outstanding:
Basic		12,154,300			11,955,400			12,060,842			11,798,810			11,490,166			11,386,258			11,467,248
Diluted		12,628,862			12,463,367			12,548,059			12,159,620			12,052,118			11,728,844			11,585,704
Financial Condition Data: (2)
Investment securities	$	215,494		$	211,237		$	220,051		$	204,266		$	188,689		$	227,346		$	229,792
Total loans (including loans held for sale) (3)		1,673,778			1,419,282			1,623,875			1,308,836			1,101,112			931,046			912,550
Total assets (4)		1,994,569			1,695,241			1,913,787			1,581,564			1,351,279			1,217,796			1,204,940
Total deposits		1,628,934			1,291,626			1,500,058			1,204,125			1,021,757			904,796			945,102
Other borrowings		147,908			202,678			200,065			183,850			199,282			195,367			150,498
Subordinated debentures		72,180			72,180			72,180			72,180			25,787			25,787			25,787
Total shareholders’ equity		129,734			114,906			125,984			109,935			96,372			85,125			73,239
Mortgage servicing portfolio		126,202			122,751			125,353			124,366			107,733			91,120			94,545
Performance Ratios:
Return on average assets		1.08	%		1.02	%		1.03	%		0.99	%		1.05	%		0.96	%		0.87	%
Return on average equity		16.73			14.99			15.80			14.59			14.94			14.87			14.89
Net interest margin		4.42			3.96			4.16			3.80			3.75			3.53			3.57
Ratio of total dividends declared to net income		16.96			20.04			18.14			19.87			18.87			15.52			16.44
Efficiency ratio (5)		48.94			56.11			51.31			54.95			56.92			59.62			60.93
Average assets per employee (6)	$	5,502		$	4,955		$	5,098		$	4,382		$	3,938		$	3,919		$	3,783
Asset Quality Ratios:
Nonperforming assets to total loans and other real estate owned (2)(7)		1.53	%		1.25	%		1.72	%		1.34	%		1.24	%		1.06	%		1.45	%
Nonperforming loans to total loans (2)(8)		0.83			1.11			1.43			1.22			1.17			0.99			1.32
Net loan charge-offs to average total loans		0.86			0.37			0.58			0.36			0.50			0.49			0.29
Allowance for loan losses to total loans (2)(4)		1.17			1.09			1.17			1.15			1.01			1.18			1.26
Allowance for loan losses to nonperforming loans (2)(4)(8)		141.91			97.86			82.00			94.31			86.49			118.98			95.82

(continued)

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	As of and for the Three Months Ended March 31,						As of and for the Years Ended December 31,
	2005			2004			2004			2003			2002			2001			2000
Capital Ratios:
Average total shareholders’ equity to average assets		6.47	%		6.83	%		6.51	%		6.75	%		7.04	%		6.44	%		5.81	%
Tangible equity to tangible assets (2)(4)(9)		6.49			6.77			6.57			6.94			7.12			6.97			6.06
Tier 1 capital to risk-weighted assets (2)		11.03			11.10			10.88			11.13			10.38			11.15			10.36
Total capital to risk-weighted assets (2)		13.89			14.63			13.92			14.90			11.42			12.34			11.68
Leverage ratio		8.75			9.21			8.61			9.32			8.99			8.84			8.08

(1) All share and per share information has been restated to reflect the three-for-two stock split effected in the form of a stock dividend paid August 29, 2001, and the two-for-one stock split effected in the form of a stock dividend paid August 29, 2003.

(2) At period end.

(3) Net of unearned discounts but before deduction of allowance for loan losses.

(4) Reflects the retroactive reclassification of the allowance related to unfunded loan commitments from the allowance for loan losses to a reserve for unfunded loan commitments, which is now shown as a liability on the statement of financial condition.

(5) The efficiency ratio is calculated by dividing other expenses by the total of net interest income plus total other income.

(6) Average assets per employee is calculated by dividing year-to-date average assets by the number of FTE employees at period end.

(7) Nonperforming assets consist of nonperforming loans and other real estate owned.

(8) Nonperforming loans consist of nonaccrual loans, loans contractually past due 90 days or more, and loans with restructured terms.

(9) Tangible equity to tangible assets is calculated by dividing total shareholders’ equity minus goodwill by total assets minus goodwill. Mortgage loan and other loan servicing intangibles are not subtracted for purposes of this calculation.

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RISK FACTORS

Investing in our common stock involves risks. You should carefully consider the following risk factors before you decide to buy our common stock. The risk factors may cause our future earnings to be lower or our financial condition to be less favorable than we expect. In addition, other risks of which we are not aware, or which we do not believe are material, may cause earnings to be lower, or hurt our financial condition. You should also consider the other information in this prospectus, as well as in the documents incorporated by reference into this prospectus.

We may be unable to execute our growth strategy.

We have pursued, and intend to continue to pursue, an internal growth strategy, the success of which will depend primarily on generating an increasing level of loans and funding at acceptable risk and expense. There can be no assurance that we will be successful in continuing our growth strategy, however, since it depends upon economic conditions, our ability to identify appropriate markets for expansion, our ability to recruit and retain qualified personnel, our ability to fund growth at reasonable cost, sufficient capital, competitive factors, banking laws, and other factors described in this prospectus.

We intend to use the proceeds of the offering to support further growth in the level of our assets and deposits and the number of our offices, including offices in new markets that may be considerable distances from our current markets and executive headquarters. We cannot be certain as to our ability to manage increased levels of assets and liabilities, or offices in these new markets, without increased expenses and higher levels of non performing assets. We may be required to make additional investments in equipment and personnel to manage higher asset levels and loan balances, which may adversely affect earnings, shareholder returns, and our efficiency ratio. Increases in operating expenses or nonperforming assets may decrease the value of our common stock.

In addition, in the future we may acquire banks, branches of other financial institutions, or other businesses. We cannot assure you that we will be able to adequately or profitably manage any such acquisitions. The acquisition of banks, bank branches, and other businesses involves risks, including exposure to unknown or contingent liabilities, the uncertainties of asset quality assessment, the difficulty and expense of integrating the operations and personnel of the acquired companies with ours, the potential negative effects on our other operations of the diversion of management’s time and attention, and the possible loss of key employees and customers of the banks, businesses, or branches we acquire. Our failure to execute our internal growth strategy or our acquisition strategy could adversely affect our business, results of operations, financial condition and future prospects.

Changes in interest rates and other factors beyond our control may adversely affect our earnings and financial condition.

Our net income depends to a great extent upon the level of our net interest income. Changes in interest rates can increase or decrease net interest income and net income. Net interest income is the difference between the interest income we earn on loans, investments and other interest-earning assets, and the interest we pay on interest-bearing liabilities, such as deposits and borrowings. Net interest income is affected by changes in market interest rates, because different types of assets and liabilities may react differently, and at different times, to market interest rate changes. When interest-bearing liabilities mature or reprice more quickly than interest-earning assets in a period, an increase in market rates of interest could reduce net interest income. Similarly, when interest-earning assets mature or reprice more quickly than interest-bearing liabilities, falling interest rates could reduce net interest income.

Changes in market interest rates are affected by many factors beyond our control, including inflation, unemployment, money supply, international events, and events in world financial markets. We attempt to manage our risk from changes in market interest rates by adjusting the rates, maturity, repricing, and balances of the different types of interest-earning assets and interest-bearing liabilities, but interest rate risk management techniques are not exact. As a result, a rapid increase or decrease in interest rates could have an adverse effect on our net interest margin and results of operations. Changes in the market interest rates for

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types of products and services in our various markets also may vary significantly from location to location and over time based upon competition and local or regional economic factors. At March 31, 2005, our interest rate sensitivity simulation model projected that net income would decrease by 9.01% if interest rates immediately fell by 100 basis points, and would increase by 12.73% if interest rates immediately rose by 100 basis points. The model projected that net income would decrease by 5.72% if interest rates gradually fell by 100 basis points over a one-year period, and would increase by 7.79% if interest rates gradually rose by 100 basis points over a one-year period. The results of our interest rate sensitivity simulation model depend upon a number of assumptions which may not prove to be accurate. There can be no assurance that we will be able to successfully manage our interest rate risk.

Changes in local economic conditions could adversely affect our business.

Our commercial and commercial real estate lending operations are concentrated in the metropolitan areas of Stillwater, Oklahoma City, and Tulsa, Oklahoma; Dallas, Austin, and San Antonio, Texas; and Wichita and Kansas City, Kansas. Our success depends in part upon economic conditions in these markets. Adverse changes in economic conditions in these markets could reduce our growth in loans and deposits, impair our ability to collect our loans, increase our problem loans and charge-offs, and otherwise negatively affect our performance and financial condition.

Adverse changes in healthcare-related businesses could lead to slower loan growth and higher levels of problem loans and charge-offs.

We have a substantial amount of loans to individuals and businesses involved in the healthcare industry, including business and personal loans to physicians, dentists and other healthcare professionals, and loans to for-profit hospitals, nursing homes, suppliers and other healthcare-related businesses. At March 31, 2005, $370.2 million of our loans, or 29% of our portfolio loans (excluding loans held for sale), involved loans to individuals and businesses in the healthcare industry. Our strategy calls for continued growth in healthcare lending. This concentration exposes us to the risk that adverse developments in the healthcare industry could hurt our profitability and financial condition as a result of increased levels of nonperforming loans and charge-offs, and reduced loan demand and deposit growth.

Income from our secondary market activities can vary significantly from year to year. Our ability to conduct student lending activities and the profitability of our student lending operations are highly dependent on Sallie Mae and federal law.

Our secondary market activities, which consist of student lending to post-secondary students and residential mortgage lending, contribute a significant portion of our consolidated net income. The volume of residential mortgage and mortgage loans and profits depend on market interest rates, economic conditions in our markets, and competition, and can vary significantly from year to year. A significant increase in interest rates would be likely to reduce residential lending loan volume and profits.

Our student lending activities include government guaranteed loans and private student loans. Our ability to conduct our student lending operations depends significantly on the SLM Corporation, which we refer to as Sallie Mae. Sallie Mae provides substantially all of the servicing for government guaranteed and private student loans; provides liquidity through its purchases of student loans and lines of credit; and guarantees substantially all of our private student loans through its subsidiary, HEMAR Insurance Corporation of America. The majority of our private student loans have been made to students who attend schools owned by Career Education Corporation, which we refer to as CEC, through our agreements with Sallie Mae and CEC. At March 31, 2005, approximately 56% of total student loans were private CEC-related loans. The profitability of these CEC-related loans will decrease significantly, beginning in the second quarter of 2005, due to a decision by Sallie Mae to increase its servicing fees on CEC-related credits. Future changes in servicing fees or in our ability to generate private loans from CEC and other private lenders may adversely affect our net income.

The volume and profitability of our government guaranteed student loans depends upon our ability to generate loans from schools and individuals and upon federal laws and regulations that authorize government

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guaranteed student loans made by banks and other lenders and establish their terms. Although they are not possible to predict, adverse changes in these laws and regulations may reduce, or even eliminate our ability to make government guaranteed student loans, and adversely affect our net income.

Our allowance for loan losses may not be adequate to cover our actual loan losses, which could adversely affect our earnings.

We maintain an allowance for loan losses in an amount which we believe is adequate to provide for losses inherent in the portfolio. While we strive to carefully monitor credit quality and to identify loans that may become nonperforming, at any time there are loans included in the portfolio that will result in losses, but that have not been identified as nonperforming or potential problem loans. We cannot be sure that we will be able to identify deteriorating loans before they become nonperforming assets, or that we will be able to limit losses on those loans that are identified. As a result, future additions to the allowance may be necessary. Additionally, future additions may be required based on changes in the loans comprising the portfolio and changes in the financial condition of borrowers, such as may result from changes in economic conditions, or as a result of incorrect assumptions by management in determining the allowance. Additionally, federal banking regulators, as an integral part of their supervisory function, periodically review our allowance for loan losses. These regulatory agencies may require us to increase our provision for loan losses or to recognize further loan charge-offs based upon their judgments, which may be different from ours. Any increase in the allowance for loan losses could have a negative effect on our financial condition and results of operations.

Our loan portfolio contains a high percentage of commercial and commercial real estate loans in relation to our total loans and total assets. Commercial and commercial real estate loans generally are viewed as having more risk of default than residential real estate loans or other loans or investments. These types of loans also typically are larger than residential real estate loans and other consumer loans. Because the loan portfolio contains a significant number of commercial and commercial real estate loans with relatively large balances, the deterioration of one or a few of these loans may cause a significant increase in nonperforming assets. An increase in nonperforming loans could result in: a loss of earnings from these loans, an increase in the provision for loan losses, or an increase in loan charge-offs, which could have an adverse impact on our results of operations and financial condition.

Unseasoned loans may increase the risk of credit defaults in the future.

Due to our rapid growth over the past several years, a large portion of the loans in our loan portfolio and of our lending relationships are of relatively recent origin. In general, loans do not begin to show signs of credit deterioration or default until they have been outstanding for some period of time, a process referred to as “seasoning.” As a result, a portfolio of older loans may behave more predictably than a newer portfolio. Because a significant portion of our loan portfolio is relatively new, the current level of delinquencies and defaults may not be representative of the level that will prevail when the portfolio becomes more seasoned, which may be higher than current levels. If delinquencies and defaults increase, we may be required to increase our provision for loan losses, which would adversely affect our results of operations and financial condition.

We use wholesale funding sources to supplement our core deposits, which exposes us to liquidity risk and potential earnings volatility or other adverse effects if we are unable to secure adequate funding.

We rely on wholesale funding, including Federal Home Loan Bank borrowings and brokered deposits, to supplement core deposits to fund our business. At March 31, 2005, these wholesale funding sources constituted approximately 33% of our total deposits and other borrowings. Wholesale funding sources are affected by general market conditions and the condition and performance of the borrower, and the availability of funding from wholesale lenders may be dependent on the confidence these investors have in our operations. The continued availability to us of these funding sources cannot be assured, and we may find it difficult to retain or replace them at attractive rates as they mature. Our liquidity will be constrained if we are unable to renew our wholesale funding sources or if adequate financing is not available to us in the future at acceptable rates of interest or at all. We may not have sufficient liquidity to continue to fund new loans, and we may need to liquidate loans or other assets unexpectedly in order to repay obligations as they mature. If

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we do not have adequate sources of liquidity at attractive rates, we may have to restrain the growth of assets or reduce our asset size, which may adversely affect shareholder value.

We rely on our management and other key personnel, and the loss of any of them may adversely affect our operations.

We are and will continue to be dependent upon the services of our executive management team. In addition, we will continue to depend on our ability to retain and recruit key commercial loan officers. The unexpected loss of services of any key management personnel, or the inability to recruit and retain qualified personnel in the future, could have an adverse effect on our business and financial condition.

The market price for our common stock may be highly volatile.

The market price for our common stock has fluctuated, ranging between $16.50 and $27.10 per share during the 12 months ended May 16, 2005. The overall market and the price of our common stock may continue to be volatile. There may be a significant impact on the market price for our common stock due to, among other things:

• Variations in our anticipated or actual operating results or the results of our competitors;

• Changes in investors’ or analysts’ perceptions of the risks and conditions of our business;

• The size of the public float of our common stock;

• Regulatory developments;

• The announcement of acquisitions or new branch locations by us or our competitors;

• Market conditions; and

• General economic conditions.

Additionally, the average daily trading volume for our common stock as reported on the Nasdaq National Market was approximately 32,000 shares during the twelve months ended May 16, 2005, with daily volume ranging from a low of 3,000 shares to a high of approximately 193,500 shares. There can be no assurance that a more active or consistent trading market in our common stock will develop. As a result, relatively small trades could have a significant impact on the price of our common stock.

Competition may decrease our growth or profits.

We compete for loans, deposits, and investment dollars with other banks and other financial institutions and enterprises, such as securities firms, insurance companies, savings associations, credit unions, mortgage brokers, and private lenders, many of which have substantially greater resources than ours. Credit unions have federal tax exemptions, which may allow them to offer lower rates on loans and higher rates on deposits than taxpaying financial institutions such as commercial banks. In addition, non-depository institution competitors are generally not subject to the extensive regulation applicable to institutions that offer federally insured deposits. Other institutions may have other competitive advantages in particular markets or may be willing to accept lower profit margins on certain products. These differences in resources, regulation, competitive advantages, and business strategy may decrease our net interest margin, may increase our operating costs, and may make it harder for us to compete profitably.

We will have broad discretion in applying the net proceeds of this offering and the use of proceeds may not enhance the market value of our common stock.

We have significant flexibility in applying the proceeds of this offering. We are not required to allocate the proceeds to any specific investment or transaction or other use. As part of your investment decision, you will not be able to assess or direct how we apply the net proceeds. We may not be able to fully or profitably deploy the proceeds of this offering. The price of our common stock may decline if the market does not view our use of the proceeds from this offering favorably.

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Government regulation significantly affects our business.

The banking industry is heavily regulated. Banking regulations are primarily intended to protect the federal deposit insurance funds and depositors, not shareholders. Stillwater National is subject to regulation and supervision by the Office of the Comptroller of the Currency. SNB Wichita is subject to regulation and supervision by the Office of Thrift Supervision. Southwest is subject to regulation and supervision by the Board of Governors of the Federal Reserve System. The burden imposed by federal and state regulations puts banks at a competitive disadvantage compared to less regulated competitors such as finance companies, mortgage banking companies and leasing companies. Changes in the laws, regulations, and regulatory practices affecting the banking industry may increase our costs of doing business or otherwise adversely affect us and create competitive advantages for others. Regulations affecting banks and financial services companies undergo continuous change, and we cannot predict the ultimate effect of these changes, which could have a material adverse effect on our profitability or financial condition. Federal economic and monetary policy may also affect our ability to attract deposits and other funding sources, make loans and investments, and achieve satisfactory interest spreads.

Our ability to pay dividends is limited by law and contract.

Our ability to pay dividends to our shareholders largely depends on Southwest’s receipt of dividends from Stillwater National. SNB Wichita does not currently pay dividends, and is not expected to do so during the next several years. The amount of dividends that Stillwater National may pay to Southwest is limited by federal laws and regulations. We also may decide to limit the payment of dividends even when we have the legal ability to pay them in order to retain earnings for use in our business. We also are prohibited from paying dividends on our common stock if the required payments on our subordinated debentures have not been made.

Restrictions on unfriendly acquisitions could prevent a takeover.

Our certificate of incorporation and bylaws contain provisions that could discourage takeover attempts that are not approved by the board of directors. The Oklahoma General Corporation Act includes provisions that make an acquisition of Southwest more difficult. These provisions may prevent a future takeover attempt in which our shareholders otherwise might receive a substantial premium for their shares over then-current market prices.

These provisions include supermajority provisions for the approval of certain business combinations and certain provisions relating to meetings of shareholders. Our certificate of incorporation also authorizes the issuance of additional shares without shareholder approval on terms or in circumstances that could deter a future takeover attempt.

In addition, we have adopted a shareholder rights plan designed to protect our shareholders against acquisitions that our board of directors believes are unfair or otherwise not in the best interests of Southwest and its shareholders. Under the rights plan, adopted in 1999 and expiring in 2009, each holder of record of our common stock, subject to the limits of the rights plan, has received, or will receive, one right per common share. The rights generally become exercisable if an acquiring party accumulates, or announces an offer to acquire, 10% or more of our voting stock. Each right entitles the holder (other than the acquiring party) to buy, under specified circumstances, shares of our common stock or equivalent securities, or shares of the acquiror’s securities, having a value of twice the right’s exercise price. Under the rights plan, we also may exchange each right, other than rights owned by an acquiring party, for a share of our common stock or equivalent securities.

Future sales of our common stock or other securities may dilute the value of our common stock.

In many situations, our board of directors has the authority, without any vote of our shareholders, to issue shares of our authorized but unissued stock, including shares authorized and unissued under our stock option plans. In the future, we may issue additional securities, through public or private offerings, in order to raise additional capital. Any such issuance would dilute the percentage of ownership interest of existing shareholders and may dilute the per share book value of the common stock. In addition, option holders may

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exercise their options at a time when we would otherwise be able to obtain additional equity capital on more favorable terms.

The sale, or availability for sale, of a substantial number of shares of common stock in the public market as a result of or following this offering could adversely affect the price of our common stock and could impair our ability to raise additional capital through the sale of equity securities.

CAUTIONARY NOTICE REGARDING FORWARD-LOOKING STATEMENTS

We make forward-looking statements in this prospectus that are subject to risks and uncertainties. We intend these statements to be covered by the safe harbor provision for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. These statements often are identifiable by the use of the words “estimate,” “goal,” “assess,” “project,” “pro forma,” “believe,” “intend,” “plan,” “anticipate,” “expect,” “target,” “objective,” “assumption,” and similar words.

These forward-looking statements include:

• statements of our goals, intentions, and expectations;

• estimates of risks and of future costs and benefits;

• expectations regarding our future financial performance and the financial performance of our operating segments;

• assessments of loan quality, probable loan losses, and the amount and timing of loan payoffs;

• assessments of liquidity, off-balance sheet risk, and interest rate risk; and

• statements of our ability to achieve financial and other goals.

These forward-looking statements are subject to significant uncertainties because they are based upon: the amount and timing of future changes in interest rates, market behavior, and other economic conditions; future laws, regulations and accounting principles; and a variety of other matters. Because of these uncertainties, the actual future results may be materially different from the results indicated by these forward-looking statements. In addition, our past growth and performance do not necessarily indicate our future results. For other factors, risks and uncertainties that could cause our actual results to differ materially from estimates and projections contained in forward-looking statements, please read the “Risk Factors” section beginning on page 8.

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USE OF PROCEEDS

Based on an assumed public offering price of $18.58 per share, the last reported sale price of our common stock on the Nasdaq National Market on May 16, 2005, we estimate that the net proceeds from the sale by us of 2,100,000 shares of our common stock in this offering will be $36.2 million ($41.7 million if the underwriters’ over-allotment option is exercised in full), after deducting the underwriting discount and the aggregate offering expenses payable by us.

We intend to use the net proceeds of the offering:

• To support continued expansion using our niche banking model in our current markets and carefully selected new markets;

• To support funding and asset growth using our community banking model in favorable markets;

• To support higher levels of secondary market lending to make full use of capital while our core banking assets grow; and

• For general corporate purposes, including investment in Stillwater National or SNB Wichita.

We anticipate that a part of our planned banking expansion may be accomplished through acquisitions of existing banks, as well as through establishment of new offices. We do not, however, have any specific plans, arrangements, agreements or understandings with any other person for any acquisitions, or for the establishment of new branches or other offices.

Pending such uses, we may invest the net proceeds in marketable investment securities, short-term, interest-bearing assets including federal funds transactions, interest-bearing deposits in other banks and similar investments.

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PRICE RANGE OF COMMON STOCK AND DIVIDENDS

Historical Stock Prices.     Our common stock is traded on the Nasdaq National Market under the symbol “OKSB.” At May 16, 2005, there were approximately 2,500 record holders of our common stock. The following table shows the range of high and low sale prices for our common stock as reported on the Nasdaq National Market for the periods indicated and the cash dividends declared per share during those periods. All share price and dividend information has been adjusted to reflect the two-for-one stock split effected in the form of a stock dividend paid on August 29, 2003.

	High		Low		Dividends Declared
2003
First Quarter	$	13.36	$	11.07	$	0.0625
Second Quarter		13.71		11.18		0.0625
Third Quarter		17.83		13.63		0.0625
Fourth Quarter		18.91		14.37		0.0625
2004
First Quarter	$	18.94	$	16.11	$	0.07
Second Quarter		18.75		15.75		0.07
Third Quarter		22.21		17.70		0.07
Fourth Quarter		27.10		21.50		0.07
2005
First Quarter	$	25.45	$	17.11	$	0.075
Second Quarter (through May 16, 2005)		19.40		16.78		—

Dividend Policy.     Holders of our common stock are entitled to receive dividends that our board of directors may declare from time to time. Our board of directors establishes the dividend amount each quarter. In making this decision, the board considers operating results, financial condition, capital adequacy, regulatory requirements, shareholder returns, and other factors.

Our ability to pay dividends largely depends upon Southwest’s receipt of dividends from Stillwater National. SNB Wichita does not currently pay dividends, and is not expected to do so during the next several years. The amount of dividends that Stillwater National may pay to Southwest is limited by federal laws and regulations. Bank regulatory agencies also have authority to prohibit a bank or bank holding company from paying dividends if such payment is deemed to be an unsafe or unsound practice. In addition, we are prohibited from paying dividends on our common stock if the required payments on our subordinated debentures have not been made.

Regular dividends have been declared and paid every year since 1981, the year Southwest was organized. We have increased our dividends per common share each year since going public in 1993. We currently expect to continue to pay quarterly cash dividends, although there can be no assurance that we will continue to do so. See “Risk Factors,” beginning on page 8.

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CAPITALIZATION

The following table sets forth our capitalization at March 31, 2005. Our capitalization is presented on a historical basis, on an as adjusted basis giving effect to our common stock repurchase, on an as adjusted basis giving effect to our common stock repurchase and the sale of the shares offered by this prospectus, and on an as adjusted basis giving effect to our common stock repurchase, the sale of shares offered by this prospectus, and the redemption of our $25.8 million of 9.3% Junior Subordinated Deferrable Interest Debentures, assuming:

• the estimated net proceeds to us from the sale of 2,100,000 shares of common stock in this offering, based on an assumed public offering price of $18.58 per share, the last reported sale price of our common stock as reported on the Nasdaq National Market on May 16, 2005, after deducting the underwriting discounts and aggregate offering expenses payable by us, are $36.2 million; and

• the underwriters’ over-allotment option is not exercised.

The following information should be read in conjunction with our Management’s Discussion and Analysis of Financial Condition and Results of Operations, and our consolidated financial statements, including the accompanying notes, which are contained in our Annual Report on Form 10-K for the year ended December 31, 2004 and our Quarterly Report on Form 10-Q for the quarter ended March 31, 2005, each of which is incorporated by reference in this prospectus.

	Actual			As Adjusted for the Share Repurchase(1)			As Adjusted for the Share Repurchase and the Offering			As Adjusted for the Share Repurchase, the Offering, and the Redemption(2)
Long-term debt:
Subordinated debentures	$	72,180		$	72,180		$	72,180		$	46,393
Shareholders’ equity:
Serial preferred stock—
Undesignated, $1 par value; 1,000,000 shares authorized; none issued		—			—			—			—
Series B, $1 par value; 1,000,000 shares authorized; none issued		—			—			—			—
Common stock, $1 par value; 20,000,000 shares authorized; 12,243,042 shares issued and outstanding actual and as adjusted for the share repurchase; 14,343,042 shares issued and outstanding as adjusted for the share repurchase and the offering		12,243			12,243			14,343			14,343
Additional paid in capital		8,347			8,347			42,424			42,424
Retained earnings		112,377			112,316			112,316			111,723
Accumulated other comprehensive income		(2,709	)		(2,709	)		(2,709	)		(2,709	)
Treasury stock at cost, 49,915 shares actual; 739,711 shares as adjusted		(524	)		(12,940	)		(12,940	)		(12,940	)
Total shareholders’ equity		129,734			117,257			153,434			152,841
Total capitalization	$	201,914		$	189,437		$	225,614		$	199,234
Consolidated capital ratios:
Average equity to average total assets		6.47	%		5.88	%		7.55	%		7.52	%
Tangible equity to tangible assets		6.49			5.91			7.59			7.56
Leverage ratio		8.75			7.97			10.19			9.82
Tier 1 risk-based capital ratio		11.03			10.03			12.90			12.43
Total risk-based capital ratio		13.89			13.16			15.27			13.68

(1) On May 13, 2005, we entered into a Selling Shareholder Agreement with Betty B. Kerns, the Joyce P. Berry Revocable Trust, the Joe M. Berry Trust, the Berry Charitable Remainder Trust, and BKP, L.L.C. This agreement provides for the sale by these selling shareholders of a total of 689,796 shares of our common stock at a price of $18.00 per share, and for the cancellation of all of the outstanding stock options previously granted to Ms. Kerns in return for a payment equal to the excess of $18.00 over the exercise price per share of options to purchase 10,826 shares that were exercisable by Ms. Kerns on

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May 13, 2005. The total consideration payable by us to the selling shareholders under the agreement is approximately $12.5 million. See “Recent Developments” on page 5.

(2)

We previously announced that we intend to redeem all of the $25.8 million of 9.30% Junior Subordinated Deferrable Interest Debentures due 2027, effective June 24, 2005. The redemption of the subordinated debentures will be concurrent with the redemption of the 9.30% Cumulative Trust Preferred Securities issued by Southwest’s subsidiary, SBI Capital Trust, which holds all of these subordinated debentures. These trust preferred securities were originally issued in June 1997, and are listed on the Nasdaq National Market under the symbol “OKSBO.” We are funding this redemption with proceeds from our issuance of trust preferred securities and subordinated debentures in October 2003. We have invested those proceeds in marketable securities pending issuance of federal regulatory capital rules for trust preferred securities, which occurred earlier this year. We expect that the write-off of unamortized costs in connection with the redemption will reduce net income in the second quarter of 2005 by approximately $593,000. We believe that the redemption will benefit net income in future periods as the subordinated debentures are replaced with funds that bear lower interest rates.

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MANAGEMENT

The following table sets forth information regarding the executive officers of Southwest, Stillwater National, and SNB Wichita.

Name	Age	Position
Kerby E. Crowell	55	Executive Vice President, Chief Financial Officer, and Secretary of Southwest and Stillwater National; Director, Chief Financial Officer, and Secretary of SNB Wichita
L. Allen Glenn	35	Managing Director, Business Consulting Group, Inc., Vice President, Stillwater National
Steven M. Gobel	53	Executive Vice President, Stillwater National
Rick Green	57	President, Chief Executive Officer, and Director and Vice Chairman of the Boards of Southwest and Stillwater National, Director and Vice Chairman of the Board of SNB Wichita
Steven N. Hadley	47	President, SNB Bank of Wichita
Rex E. Horning	53	President, Stillwater Division of Stillwater National
Jerry L. Lanier	57	Executive Vice President and Chief Lending Officer of Stillwater National
Len McLaughlin	52	President, Dallas Division of Stillwater National
J. Randall Mills	50	President, Healthcare Strategic Support, Inc.
Steven M. Peterson	40	President, Austin Division of Stillwater National
Joseph P. Root	41	President, Central Oklahoma Division of Stillwater National
Kimberly G. Sinclair	49	Executive Vice President and Chief Administrative Officer of Stillwater National
Charles H. Westerheide	56	Executive Vice President and Treasurer of Stillwater National
David L. York	58	President, Tulsa Division of Stillwater National

The principal occupations and business experience of each executive officer of Southwest are shown below.

Kerby E. Crowell has served as Executive Vice President, Treasurer, and Chief Financial Officer of Southwest and Stillwater National since 1986, became Secretary of Southwest and Stillwater National in 2000, and was named Chief Financial Officer, Director, and Secretary of SNB Wichita in 2003. Mr. Crowell joined Stillwater National in 1969. He is a Past President and Board member of the Oklahoma City Chapter of the Financial Executives Institute and a Board member of the Independent Community Bankers of America’s, referred to as ICBA, credit card subsidiary, and MetaFund Corporation (an Oklahoma Community Development Financial Institution). He is past President and Director of the Oklahoma 4-H Foundation, Inc., Director and past President of the Payne County Affiliate of the American Diabetes Association, past President of the Stillwater Breakfast Kiwanis Club, the Bank Administration Institute’s Northern Oklahoma Chapter, and the North Central Chapter of Certified Public Accountants, a past member of the Payments and Technology Committee of the ICBA, and past Vice Chairman of the ICBA’s Bank Services Committee. He has also served on the Federal Reserve’s Industry Advisory Group on Electronic Check Presentment. Mr. Crowell is a graduate of the Leadership Stillwater Class XI.

L. Allen Glenn serves as Managing Director of the Business Consulting Group, Inc., a management consulting subsidiary of Southwest, and as a Vice President of Stillwater National. Mr. Glenn previously served as Vice President of Business Consulting Group, beginning in December 2001. From 2000 until

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joining Business Consulting Group and Stillwater National in December 2001, Mr. Glenn was President of Glenn Solutions, Inc., a management consulting firm that specialized in developing strategic and operational solutions for national retailers to improve their profitability and service levels. From 1995 to 2000, Mr. Glenn was a manager with Kurt Salmon Associates, an international management consulting firm to the retail consumer products and health care industries.

Steven M. Gobel serves as Executive Vice President, Audit Facilitator, and Associate Chief Financial Officer of Stillwater National. From 1990 until joining Stillwater National in September 2000, Mr. Gobel served as Senior Vice President-Finance and in other positions with Bank of America and predecessor institutions in Oklahoma and Kansas (previous institutions included NationsBank, Boatmen’s Bank of St. Louis, Bank IV of Wichita, Kansas, and Fourth National Bank of Tulsa). Mr. Gobel is a past member of the Board of Directors of the YMCA of Greater Tulsa and a past member and Chairman of the Board of Managers for the Downtown Branch of the YMCA of Greater Tulsa. From 1987 to 1990, Mr. Gobel served as a Vice President and Manager of Financial Reporting and Financial Planning for Sooner Federal Savings and Loan of Oklahoma. He is a Certified Public Accountant and prior to 1987 spent twelve years working for Touche Ross and Coopers & Lybrand in Tulsa, Oklahoma, New York City, and Milwaukee, Wisconsin.

Rick Green was appointed the Chief Executive Officer of Southwest effective January 1, 1999. Mr. Green joined Stillwater National in 1972, and prior to becoming Chief Executive Officer served as Chief Operating Officer, President of the Central Oklahoma division, and Executive Vice President of Stillwater National. He is a member of the Oklahoma City and Edmond Chambers of Commerce and has served as Chair/Ambassador of the Stillwater Chamber of Commerce, on the Oklahoma State University Alumni Association Homecoming and Honor Students Committees, as Chairman of Payne County Youth Services, as Co-Chairman of the United Way of Stillwater Fund Drive, and as a member of the Advisory Board of the Oklahoma State University Technical Institute. He is a member of the Commercial Real Estate Association of Oklahoma City, the Oklahoma and Oklahoma City Homebuilders Associations, and past member of the Stillwater Medical Center Committee on Physician Recruitment. Mr. Green is also a member of Leadership Stillwater and Leadership Oklahoma City. Mr. Green continues to be active as an alumnus of Oklahoma State University, serving on various committees and boards, including the Board of Governors of the Oklahoma State University Development Foundation, and is a member of the Oklahoma State University College of Business Alumni Hall of Fame.

Steven N. Hadley was named President and CEO of SNB Wichita in October 2004. Mr. Hadley has over twenty-three years of banking experience. Prior to joining SNB Wichita, Mr. Hadley spent four years with Commerce Bank in their Wichita and Garden City, Kansas markets. Before that, he was with Bank of America in Garden City, Kansas. Mr. Hadley holds a bachelors degree in Agricultural Economics from Kansas State University. He is a member of the booster club for the KAPAUN Mt. Carmel High School and is involved in the Wichita Swim Club and the St. Thomas Aquinas Catholic Church.

Rex E. Horning was appointed President of the Stillwater Division of Stillwater National in May 2001. Mr. Horning previously served as Senior Vice President of Central National Bank and Commerce Bank in Wichita, Kansas from 1998 to May 2001, and as President and Chief Executive Officer of First State Bank and Trust Company, Pittsburg, Kansas, from 1991 to 1998. Mr. Horning currently serves on the Executive Committee of the Oklahoma State University Alumni Association, is a Trustee for the Oklahoma State University Foundation, is Board Chairman of the Stillwater Chamber of Commerce, serves on the Board of Directors of the State Chamber of Commerce, and is President of Oklahoma State University’s William S. Spears’ College of Business Associates.

Jerry L. Lanier was appointed Executive Vice President and Chief Lending Officer of Stillwater National in 2001. Mr. Lanier previously served as Executive Vice President-Credit Administration beginning in December 1999, supervising this area company-wide, and from January 1998 to December 1999, served as Senior Vice President in Credit Administration. From 1992 until joining Stillwater National in 1998, Mr. Lanier was a consultant specializing in loan review. During this same period he also served as court-appointed receiver for a number of Oklahoma-based insurance companies. From 1982 to 1992, Mr. Lanier served as President of American National Bank and Trust Co. of Shawnee, Oklahoma including service as Chief Executive Officer from 1987 to 1992. From 1970 to 1981, he was a National Bank Examiner in

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Oklahoma City, Oklahoma and Dallas, Texas, and, while an examiner, served as Regional Director of Special Surveillance for the OCC from 1979 to 1981. Mr. Lanier has served as United Way Drive Chairman and President; Chairman of the Shawnee Advisory Board of Oklahoma Baptist University; Director of the Shawnee Chamber of Commerce; Director and Chairman of the Youth and Family Resource Center; and President and Trustee of the Shawnee Educational Foundation.

Len McLaughlin was appointed as President of SNB Bank of Dallas, the Texas Division of Stillwater National, in May 2002. Mr. McLaughlin previously served as President and CEO of First Independent National Bank in Plano, Texas, and as President/CEO of Preston National Bank in Dallas, Texas. From 1989 to 1998, Mr. McLaughlin was with Compass Bancshares, serving as President of a subsidiary bank, Central Bank N.A. in Anniston, Alabama; and later as Chief Retail Executive for Compass Bank in Dallas, Texas. Mr. McLaughlin began his banking career with First National Bank of Boston’s Dallas, Texas office. He has served as Chairman of the March of Dimes fund drive, United Way Fund Drive Chairman, President of the local chapter of the American Cancer Society, Director of the Little Light House, and is Honorary Co-Chairman of the Business Advisory Council of the National Republican Congressional Committee.

J. Randall Mills was appointed President of Healthcare Strategic Support, Inc. in 2003. Mr. Mills holds a Bachelor of Science degree in Accounting from Southwest Missouri State University; a Master of Health Administration from the University of Colorado; and a PhD in Sociology from Oklahoma State University. Prior to his employment with Healthcare Strategic Support, Inc., he was a healthcare consultant for Madole & Wagner, PLLC where he was responsible for marketing, administration, and client services for individual physicians, medical groups, and hospital clients on medical group practice, managed care, marketing, networking, strategic planning, and development issues. He is a fellow of the American College of Healthcare Executives, and a member of the Medical Group Management Association, American Society of Certified Public Accountants, and Oklahoma Society of Certified Public Accountants.

Steven M. Peterson was appointed President of SNB Bank of Austin in September 2004. Mr. Peterson previously served as City President for Compass Bank in Williamson County, Texas, and Commerce Bank in Wichita, Kansas from 1998 to August 2004. Mr. Peterson began his banking career with Fourth Financial Holding Company in Wichita, Kansas. Mr. Peterson currently serves as the President of the Georgetown Symphony and Director of the Chamber of Commerce. He has served as the Chairman of the 100,000 economic committee.

Joseph P. Root was appointed President of the Central Oklahoma Division of Stillwater National in 1997. Previously, Mr. Root was Senior Vice President in the Central Oklahoma division. Prior to joining Stillwater National in 1992, Mr. Root served as Credit Analyst from November 1987 to April 1989 and Private Banking Officer from May 1989 to July 1992 with Comerica Bank in Dallas, Texas. He is a member of the Advisory Board of the Greater Oklahoma City Chamber of Commerce, a member of the State Chamber of Commerce of Oklahoma, a graduate of Leadership Oklahoma City, and President of Infant Crisis Services, Inc., a local charitable organization that provides basic necessities to underprivileged children.

Kimberly G. Sinclair was appointed Chief Administrative Officer in 1995 and has been Executive Vice President of Stillwater National since 1991. Prior to 1991, she had been Senior Vice President and Chief Operations Officer of Stillwater National since 1985. Ms. Sinclair joined Stillwater National in 1975. She is a member of the Stillwater Junior Service Sustainers, and serves on the Executive Board of Directors for the Stillwater United Way, and chairs the annual Day of Caring. She is past Treasurer of the Board of Trustees of the Stillwater Public Education Foundation, and a graduate of the Leadership Stillwater Class IX. She has been an Ambassador with the Stillwater Chamber of Commerce and active with the Pioneer Booster Club and Stillwater PTA.

Charles H. Westerheide was appointed Executive Vice President and Treasurer of Stillwater National in 2000. Prior to that he served as Senior Vice President and Treasury Manager. He joined Stillwater National in 1997, coming from Bank of America (previously Bank IV and NationsBank), Wichita, Kansas, where he served as Treasury/Funding Manager. Prior to joining Bank IV, Mr. Westerheide served as Executive Vice President and Chief Financial Officer of Security Bank and Trust Co., Ponca City, Oklahoma. Mr. Westerheide has held a number of community leadership positions including Chairman of the Ponca City Chamber of

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Commerce, President of the Ponca City Foundation for Progress, Inc., and a director and officer of numerous community foundations and clubs. Mr. Westerheide is a graduate of Leadership Oklahoma, Class II.

David L. York was appointed President of the Tulsa Division in March 2004. Mr. York came to Stillwater National with over thirty years in the Tulsa banking market, most recently serving as Senior Vice President and Manager of the Professional Banking Group of The F&M Bank & Trust Company in Tulsa from 1989 to 2004. From 1983 to 1989, Mr. York served in various management and senior lending positions with Utica National Bank & Trust Company, which was acquired by F&M Bank. Mr. York began his banking career with the First National Bank and Trust Company of Tulsa in 1973 and served there until 1983 in various commercial lending and management capacities. Currently, Mr. York serves on the Board of Trustees of St. Simeon’s Episcopal Home, Inc., where he was President of the Board for four years, as well as serving as Vice President of its Foundation. Additionally, Mr. York has served on the Board of Trustees of Holland Hall School as its Treasurer. Mr. York is also an Advisory Director of the Tulsa Metro Chamber of Commerce.

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SHARE OWNERSHIP OF DIRECTORS, OFFICERS AND FIVE PERCENT BENEFICIAL OWNERS

The following table sets forth as of May 13, 2005, certain information with respect to:

• the ownership of common stock by:

• each of our directors,

• each of our executive officers who was named in the summary compensation table in our proxy statement for the annual meeting of shareholders held on April 28, 2005, and

• all directors and executive officers as a group; and

• each person known by us to be the beneficial owner of 5% or more of our outstanding common stock.

The number and percentage of shares beneficially owned after the share repurchase and the offering assumes that:

• we sell 2,100,000 shares of common stock in this offering; and

• the underwriters do not exercise their option to purchase additional shares in this offering to cover over-allotments, if any; and

• we repurchase 689,796 shares beneficially owned by Betty B. Kerns. See “Recent Developments” on page 5.

For purposes of the table below, unless otherwise noted, the number of shares of common stock outstanding and related percentages exclude:

• 1,035,982 shares that we may issue upon the exercise of stock options outstanding as of March 31, 2005, at a weighted average exercise price of $10.93 per share; and

• 485,427 additional shares at that we may issue under the Southwest Bancorp 1999 Stock Option Plan, as amended, at March 31, 2005.

Unless otherwise indicated, based on information furnished by such shareholders, we believe that each person has sole voting and investment power with respect to all shares beneficially owned by such person.

	Shares Beneficially Owned as of May 13, 2005(1)						Shares Beneficially Owned After the Share Repurchase and the Offering(1)
	Number			Percentage(2)			Number			Percentage(2)
James E. Berry II		251,996	(3)		2.06	%		251,996	(3)		1.85	%
Thomas D. Berry		62,057	(4)		*			62,057	(4)		*
Joe Berry Cannon		89,598	(5)		*			89,598	(5)		*
Rick Green		159,702	(6)		1.29			159,702	(6)		1.16
J. Berry Harrison		116,902	(7)		*			116,902	(7)		*
Erd M. Johnson		200,733	(8)		1.65			200,733	(8)		1.47
David P. Lambert		38,233	(9)		*			38,233	(9)		*
Linford R. Pitts		36,350	(10)		*			36,350	(10)		*
Robert B. Rodgers		71,922	(11)		*			71,922	(11)		*
Russell W. Teubner		52,534	(12)		*			52,534	(12)		*
Kerby E. Crowell		97,515	(13)		*			97,515	(13)		*
Jerry I. Lanier		44,134	(14)		*			44,134	(14)		*
Kimberly G. Sinclair		55,108	(15)		*			55,108	(15)		*
Joseph P. Root		17,468	(16)		*			17,468	(16)		*
All Directors and Executive Officers as a Group (23 persons)		1,418,961	(17)		11.13			1,418,961	(17)		10.02
FMR Corp		1,191,975	(18)		9.77			1,191,975	(18)		8.76
Betty B. Kerns		710,477	(19)		5.82			8,955	(19)		*
Delphi Management, Inc.		614,739	(20)		5.04			614,739	(20)		4.52

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* Less than one percent of shares outstanding.

(1) Beneficial ownership is defined by rules of the Securities and Exchange Commission, and includes shares that the person has or shares voting or investment power over and, for purposes of this chart, shares that the person has a right to acquire within 60 days from May 13, 2005. Unless otherwise indicated, ownership is direct and the named individual exercises sole voting and investment power over the shares listed as beneficially owned by such person. A decision to disclaim beneficial ownership is made by the individual, not Southwest.

(2) Calculated based upon shares reported as beneficially owned by the listed persons and shares of our common stock outstanding as of May 13, 2005. In calculating the percentage ownership of each named individual and the directors and executive officers as a group, the number of shares outstanding includes any shares that the person or the group has the right to acquire within 60 days of May 13, 2005.

(3) Excludes 28,423 shares held by his spouse and children and includes 10,826 shares that Mr. Berry has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(4) Excludes 4,639 shares held by the Tom D. Berry Profit Sharing Plan. Includes 10,826 shares that Mr. Berry has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(5) Excludes 54,810 shares beneficially owned by his spouse, as trustee. Includes 10,826 shares that Mr. Cannon has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(6) Excludes 7,220 shares held by his spouse and children. Includes 159,702 shares that Mr. Green has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(7) Includes 10,826 shares that Mr. Harrison has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(8) Excludes 35 shares held by his spouse. Includes 9,155 shares held by Johnson Oil Partnership of which Mr. Johnson is a general partner. Includes 7,175 shares that Mr. Johnson has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(9) Excludes 21,000 shares held by his spouse and 3,000 shares held by a trust of which he is co-trustee. Includes 10,826 shares that Mr. Lambert has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(10) Includes 10,826 shares that Mr. Pitts has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(11) Excludes any shares owned by his father, James W. Rodgers, Jr., and his mother, Sarah Jane Berry Rodgers. Excludes 2,276 shares held by his children. Includes 10,826 shares that Mr. Rodgers has the right to acquire with 60 days of May 13, 2005, pursuant to the exercise of stock options.

(12) Includes 10,826 shares that Mr. Teubner has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(13) Includes 76,341 shares that Mr. Crowell has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(14) Includes 43,788 shares that Mr. Lanier has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(15) Includes 43,184 shares that Ms. Sinclair has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(16) Includes 15,691 shares that Mr. Root has the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options.

(17) Includes shares held by certain directors and executive officers as custodians under Uniform Transfers to Minors Acts, by their spouses and children, and for the benefit of certain directors and executive officers as custodians under individual retirement accounts (“IRAs”) and living trusts. Includes 555,051 shares that executive officers and directors have the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options. Does not include shares beneficially owned by directors of Stillwater National Bank and Trust Company or SNB Bank of Wichita who are not also directors of Southwest.

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(18) The address of FMR Corp is 82 Devonshire Street, Boston, Massachusetts 02109.

(19) The number of shares beneficially owned as of May 13, 2005, includes 580,542 shares owned by trusts of which Ms. Kerns is a fiduciary, 100,000 shares owned by a family limited liability company, of which Ms. Kerns is a management official, 8,955 shares owned jointly with Ms. Kerns’ spouse, 900 shares of restricted stock and 10,826 additional shares that Ms. Kerns had the right to acquire within 60 days of May 13, 2005, pursuant to the exercise of stock options. Ms. Kerns resigned from our board on May 13, 2005. The address of Ms. Kerns is 4111 Deer Crossing Drive, Stillwater, Oklahoma 74074.

(20) The address of Delphi Management, Inc. is 50 Rowes Wharf, Suite 540, Boston, Massachusetts 02110.

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UNDERWRITING

Subject to the terms and conditions contained in the underwriting agreement between us and the underwriters named below, for whom Stifel, Nicolaus & Company, Incorporated is acting as representative, the underwriters have severally agreed to purchase from us and we have agreed to sell to them, an aggregate of      shares of our common stock in the numbers set forth below opposite their respective names.

Underwriters	Number of Shares
Stifel, Nicolaus & Company, Incorporated
Edward D. Jones & Co., L.L.P.
Friedman, Billings, Ramsey & Co., Inc.
Keefe, Bruyette & Woods, Inc.
SunTrust Capital Markets, Inc.
Total

Under the terms and conditions of the underwriting agreement, the underwriters are committed to accept and pay for all of the shares of our common stock in this offering, if any are taken. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of a non-defaulting underwriter may be increased or, in certain cases, the underwriting agreement may be terminated. In the underwriting agreement, the obligations of the underwriters are subject to approval of certain legal matters by their counsel, including, without limitation, the authorization and the validity of the shares of our common stock, and to various other conditions contained in the underwriting agreement, such as receipt by the underwriters of officers’ certificates and legal opinions.

The underwriters propose to offer the shares of our common stock directly to the public at the public offering price set forth on the cover page of this prospectus, and to certain selected dealers (who may include the underwriters) at this price, less a concession not in excess of $               per share of our common stock. The underwriters may allow, and the selected dealers may reallow, a concession not in excess of $         per share of our common stock to certain brokers and dealers. After the shares of our common stock are released for sale to the public, the offering price and other selling terms may from time to time be changed by the underwriters.

We have granted the underwriters an option, exercisable within 30 days after the date of this prospectus, to purchase up to      additional shares of our common stock at the initial public offering price less the underwriting discounts and commissions set forth on the cover page of this prospectus. If the underwriters purchase any of the additional shares of our common stock under this option, each underwriter will be committed to purchase the additional shares of our common stock in approximately the same proportion allocated to such underwriter in the table above. The underwriters may exercise the option only for the purpose of covering over-allotments, if any, made in connection with the distribution of our shares of common stock being offered.

The following table shows the per share, total offering price of the shares offered, the total underwriting discounts and commissions that we will pay to the underwriters, and the proceeds we will receive before expenses. The amounts are shown assuming both no exercise and full exercise of the underwriters’ over-allotment option to purchase additional shares. See “Use of Proceeds” on page 14.

	Per Share	Total if the Over- Allotment Option is Not Exercised	Total if the Over- Allotment Option is Exercised in Full
Public offering price	$	$	$
Underwriting discounts and commissions
Proceeds, before expenses, to us

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We expect to incur expenses of approximately $500,000 in connection with this offering. These expenses are estimated to include legal fees of $250,000, accounting fees of $75,000, printing costs of $75,000, and miscellaneous expenses of $100,000.

The offering of the shares of our common stock is made for delivery when, as and if accepted by the underwriters and subject to prior sale and to withdrawal, cancellation or modification of the offering without notice. The underwriters reserve the right to reject any order for the purchase of the shares of our common stock.

We and our executive officers and directors have agreed, for a period of 90 days after the date of this prospectus, not to offer, sell, contract to sell, pledge or otherwise dispose of, directly or indirectly, any shares of our common stock or securities convertible into or exchangeable or exercisable for any shares of our common stock, enter into a transaction that would have the same effect, or enter into any swap, hedge or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of our common stock, whether any of these transactions is to be settled by delivery of our common stock or other securities, in cash or otherwise, or publicly disclose the intention to make any such offer, sale, pledge or disposition, or to enter into any such transaction, swap, hedge or other arrangement, without, in each case, the prior written consent of the representatives of the underwriters. Each of the persons who agreed to sell common stock to us under the selling shareholder agreement agreed to the same selling restrictions applicable to our executive officers and directors from the date of that agreement until the earlier of the termination of the agreement or 180 days after the date of the agreement, and additionally agreed to enter into an agreement with the underwriters, upon the underwriters’ request, subjecting the selling shareholders to the same selling restrictions applicable to our executive officers, and directors for a period of 90 days after the date of the prospectus. See “Recent Developments” on page 5.

We have agreed to indemnify the several underwriters against, or contribute to payments the underwriters may be required to make in respect of, several liabilities, including liabilities under the Securities Act of 1933.

The common stock is traded on the Nasdaq National Market under the symbol “OKSB.”

In connection with the offering, the underwriters may engage in transactions that are intended to stabilize, maintain or otherwise affect the price of the shares of our common stock during and after the offering.

• Stabilizing transactions permit bids to purchase shares of our common stock so long as the stabilizing bids do not exceed a specified maximum.

• Over-allotment transactions involve sales by the underwriters of shares of our common stock in excess of the number of shares the underwriters are obligated to purchase. This creates a syndicate short position which may be either a covered short position or a naked short position. In a covered short position, the number of shares over-allotted by the underwriters is not greater than the number of shares that they may purchase in the over-allotment option. In a naked short position, the number of shares involved is greater than the number of shares in the over-allotment option. The underwriters may close out any short position by either exercising their over-allotment option and/or by purchasing shares in the open market.

• Syndicate covering transactions involve purchases of common stock in the open market after the distribution has been completed in order to cover syndicate short positions. In determining the source of shares to close out the short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared with the price at which they may purchase shares through exercise of the over-allotment option. If the underwriters sell more shares than could be covered through exercise of the over-allotment option and, therefore, have a naked short position, the position can be closed out only by buying shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that after pricing there could be downward pressure on the price of the shares in the open market that could adversely affect investors who purchase in the offering.

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• Penalty bids permit the representatives to reclaim a selling concession from a syndicate member when any shares of our common stock originally sold by that syndicate member are purchased in a stabilizing or syndicate cover transaction to cover syndicate short positions.

The effect of these transactions may be to stabilize or maintain the market price of the shares of our common stock at a level above that which might otherwise prevail in the open market. The imposition of a penalty bid may also affect the price of the shares of our common stock to the extent that it discourages resales. No representation is made as to the magnitude or effect of any such stabilization or other transactions. Such transactions may be effected on the Nasdaq National Market or otherwise and, if commenced, may be discontinued at any time.

In connection with this offering, some underwriters and any selling group members who are qualified market makers on the Nasdaq National Market may engage in passive market making transactions in our common stock on the Nasdaq National Market in accordance with Rule 103 of Regulation M under the Securities Act. Rule 103 permits passive market making during the period when Regulation M would otherwise prohibit market making activity by the participants in our common stock offering. Passive market making may occur during the business day before the pricing of our offering, before the commencement of offers or sales of our common stock. Passive market makers must comply with applicable volume and price limitations and must be identified as a passive market maker. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for the security. If all independent bids are lowered below the bid of the passive market maker, however, the bid must then be lowered when purchase limits are exceeded. Net purchases by a passive market maker on each day are limited to a specified percentage of the passive market maker’s average daily trading volume in our common stock during a specified period and must be discontinued when that limit is reached. The underwriters and other dealers are not required to engage in passive market making and may end passive market making activities at any time.

Certain of the underwriters and their affiliates have provided from time to time, and may provide in the future, investment or commercial banking services for us or our affiliates for which they have received or expect to receive customary fees and commissions.

LEGAL MATTERS

The validity of the shares of our common stock offered by this prospectus and selected other legal matters in connection with the offering will be passed upon for us by the law firms of Kennedy & Baris, L.L.P., Bethesda, Maryland and James I. Lundy, III, Attorney at Law, Washington, D.C. Certain legal matters related to this offering are being passed upon for the underwriters by the law firm of Bryan Cave LLP, St. Louis, Missouri.

EXPERTS

The consolidated financial statements of Southwest appearing in Southwest’s Annual Report (Form 10-K) for the year ended December 31, 2004 and Southwest management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2004 included therein, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements and management’s assessment are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any reports, statements or other information that we file with the SEC at the SEC’s public reference room at 450 Fifth Street, N.W., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference room. The SEC maintains a web site on the Internet at “http://www.sec.gov” that contains reports, proxy and information statements, and other information regarding companies, including Southwest Bancorp, Inc., that file electronically with the SEC. Our SEC filings also are available on our web site at http://www.oksb.com. Information on our website is not incorporated by reference into this prospectus and you should not consider information contained in our website as part of this prospectus.

We have filed a Registration Statement on Form S-3 to register the common stock to be sold in the offering. This prospectus is a part of that Registration Statement. As allowed by SEC rules, this prospectus does not contain all the information you can find in the Registration Statement or the exhibits to the Registration Statement. SEC regulations require us to “incorporate by reference” information into this prospectus, which means that important information is disclosed by referring you to another document filed separately with the SEC. The information incorporated by reference is considered part of this prospectus. Information incorporated by reference from earlier documents is superseded by information that is included in this prospectus or is incorporated by reference from more recent documents, to the extent that they are inconsistent.

DOCUMENTS INCORPORATED BY REFERENCE

This prospectus incorporates by reference the documents listed below that we have previously filed with the SEC (file no. 000-23064).

(1) Annual Report on Form 10-K for the year ended December 31, 2004;

(2) Quarterly Report on Form 10-Q for the quarter ended March 31, 2005;

(3) Current Reports on Form 8-K filed January 10, 2005, January 26, 2005, January 27, 2005, February 28, 2005, March 23, 2005, April 21, 2005, April 28, 2005, and May 17, 2005; and

(4) The description of our common stock contained in the Form 8-A relating thereto, as amended by the information contained in Part II, Item 5 of our Form 10-Q for the period ended September 30, 1999, and the description of the preferred stock purchase rights attendant to our common stock contained in the Form 8-A relating thereto.

Also incorporated by reference are additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 after the date of this prospectus and before the termination of the offering. These additional documents will be deemed to be incorporated by reference, and to be a part of, this prospectus from the date of their filing. These documents include proxy statements and periodic reports, such as Annual Reports on Form 10-K, Quarterly Reports on Form 10- Q, and, to the extent they are considered filed, Current Reports on Form 8-K. Information incorporated by reference from later filed documents supersedes information that is included in this prospectus or is incorporated by reference from earlier documents, to the extent that they are inconsistent.

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You can obtain any of the documents incorporated by reference from us, the SEC or the SEC’s Internet web site as described above. Documents incorporated by reference, including any exhibits specifically incorporated by reference therein, are available from us without charge. You may obtain copies of documents incorporated by reference by requesting them in writing or by telephone from:

Kerby E. Crowell
Executive Vice President,
Chief Financial Officer and Corporate Secretary
Southwest Bancorp, Inc.
608 South Main Street
Stillwater, Oklahoma 74074
Telephone (405) 372-2230

You should rely only on the information contained or incorporated by reference in this prospectus. We have not authorized anyone to provide you with information that is different from what is contained in this prospectus. This prospectus is dated      , 2005. You should not assume that the information contained in this prospectus is accurate as of any date other than that date.

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TABLE OF CONTENTS
	Page
Prospectus Summary	1
Risk Factors	8
Cautionary Notice Regarding Forward-Looking Statements	13
Use of Proceeds	14
Price Range of Common Stock and Dividends	15
Capitalization	16
Management	18
Share Ownership of Directors, Officers and Five Percent Beneficial Owners	22
Underwriting	25
Legal Matters	27
Experts	27
Where You Can Find More Information	28
Documents Incorporated by Reference	28

• You should rely only on the information contained in or incorporated by reference into this prospectus. We have not, and the underwriters have not, authorized anyone to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it.

• You should assume that the information appearing in this prospectus is accurate only as of the date on the front cover of this prospectus.

• We are not, and the underwriters are not, making an offer of these securities in any jurisdiction where the offer or sale is not permitted. Furthermore, you should not consider this prospectus to be an offer or solicitation relating to these securities if the person making the offer or solicitation is not qualified to do so, or it is unlawful for you to receive such an offer or solicitation.

2,100,000 Shares

Common Stock

Prospectus
                          , 2005

Stifel, Nicolaus & Company
Incorporated

Edward Jones

Friedman, Billings, Ramsey & Co., Inc.

Keefe, Bruyette & Woods

SunTrust Robinson Humphrey

PART II: INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.     Other Expenses of Issuance and Distribution

The expenses payable by the Company in connection with the Offering described in this Registration Statement are as follows:

Registration Fee	$	5,185
*Blue Sky Filing Fees and Expenses (Including counsel fees)		5,000
NASD Corporate Finance Fee		5,500
*Nasdaq Listing Fees		19,000
*Legal Fees		250,000
*Printing, Engraving and Edgar		75,000
*Accounting Fees and Expenses		75,000
*Other Expenses		65,315
Total	$	500,000

* Estimated

Item 15.     Indemnification of Directors and Officers

Section 1031 of the Oklahoma General Corporation Act sets forth circumstances under which directors, officers, employees and agents may be insured or indemnified against liability which they may incur in their capacities.

Article XV of the Amended and Restated Certificate of Incorporation of the Company provides that the Company shall indemnify any individual who is or was a director, officer, employee or agent of the Company, and any individual who serves or served at the Company’s request as a director, officer, partner, trustee, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, in any proceeding in which the individual is made a party as a result of his or her service in such capacity, if the individual acted in good faith and in a manner reasonably believed to be in, or not opposed to, the best interests of the Company and, with respect to any criminal proceeding, he or she had no reasonable cause to believe the conduct was unlawful, unless such indemnification would be prohibited by law. An individual will not be indemnified in connection with a proceeding by or in the right of the Company in which the individual was adjudged liable to the Company, unless the court in which the suit was brought determines the individual is fairly and reasonably entitled to indemnification in view of all of the relevant circumstances.

Item 16.     Exhibits

The exhibits filed as part of this registration statement are as follows:

Exhibit Number	Description
1	Form of Underwriting Agreement
4	Rights Agreement, dated as of April 22, 1999, between Southwest Bancorp, Inc. and Harris Trust & Savings Bank, as rights agent and Form of Certificate of Designations setting forth terms of Class B, Series 1 Preferred Stock of Southwest Bancorp, Inc. referred to in the rights agreement (incorporated by reference to Exhibits 1 and 2 to Current Report on Form 8-K dated April 22, 1999)
5	Opinion of Kennedy & Baris, L.L.P., previously filed
10	Selling Shareholder Agreement dated May 13, 2005, by and among the shareholders identified on Schedule I thereto and Southwest Bancorp, Inc. (incorporated by reference to Exhibit 10.1 to Current Report on Form 8-K dated May 17, 2005)
23(a)	Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm
23(b)	Consent of Kennedy & Baris, L.L.P. (included in Exhibit 5)
23(c)	Consent of James I. Lundy, III, Attorney at Law, previously filed
24	Power of Attorney, previously filed

II-1

Item 17.     Undertakings

The undersigned registrant hereby undertakes to deliver or cause to be delivered with the prospectus, to each person to whom the prospectus is sent or given, the latest annual report to security holders that is incorporated by reference in the prospectus and furnished pursuant to and meeting the requirements of Rule 14a-3 or Rule 14c-3 under the Exchange Act; and, where interim financial information required to be presented by Article 3 of Regulation S-X is not set forth in the prospectus, to deliver, or cause to be delivered to each person to whom the prospectus is sent or given, the latest quarterly report that is specifically incorporated by reference in the prospectus to provide such interim financial information.

The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to section 15(d) of the Exchange Act) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act, and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

The undersigned registrant hereby undertakes that:

(1)      For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

(2)      For the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

II-2

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Stillwater, Oklahoma, on May 18, 2005.

	SOUTHWEST BANCORP, INC.
By:	/s/ RICK GREEN Rick Green President and Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this registration statement has been signed below by the following persons in the capacities indicated on May 18, 2005.

Name	Capacity
/s/ Rick Green	President and Chief Executive Officer, Director, Vice Chairman of the Board of Directors (Principal Executive Officer)
Rick Green
/s/ Kerby E. Crowell	Executive Vice President, Chief Financial Officer and Secretary (Principal Accounting and Financial Officer)
Kerby E. Crowell
/s/ James E. Berry II*	Director
James E. Berry II
/s/ Thomas D. Berry*	Director
Thomas D. Berry
/s/ Joe Berry Cannon*	Director
Joe Berry Cannon
/s/ J. Berry Harrison*	Director
J. Berry Harrison
/s/ Erd M. Johnson*	Director
Erd M. Johnson
/s/ David P. Lambert*	Director
David P. Lambert

II-3

Name	Capacity
/s/ Linford R. Pitts*	Director
Linford R. Pitts
/s/ Robert B. Rodgers*	Chairman of the Board of Directors
Robert B. Rodgers
/s/ Russell W. Teubner*	Director
Russell W. Teubner

* By: /s/ Rick Green, pursuant to power of attorney
Rick Green, Attorney in Fact

II-4

EX-1

                                                                       EXHIBIT 1

                                2,100,000 Shares

                             SOUTHWEST BANCORP, INC.

                                  Common Stock
                            Par Value $1.00 Per Share

                             UNDERWRITING AGREEMENT

                                                                   May ___, 2005

Stifel, Nicolaus & Company, Incorporated
Edward D. Jones & Co. L.L.P.
Friedman, Billings, Ramsey & Co., Inc.
Keefe, Bruyette & Woods, Inc.
Suntrust Capital Markets, Inc.
         As Representatives of the Several Underwriters
         named in Schedule I hereto
c/o Stifel, Nicolaus & Company, Incorporated
501 North Broadway, 9th Floor
St. Louis, Missouri 63102

Ladies and Gentlemen:

         Southwest Bancorp, Inc., an Oklahoma corporation (the "Company"),
proposes to issue and sell to the several underwriters listed on Schedule I
hereto (the "Underwriters"), pursuant to the terms of this Agreement, 2,100,000
shares of the Company's common stock, par value $1.00 per share (the "Common
Stock"). The 2,100,000 shares of Common Stock to be sold to the Underwriters are
referred to as the "Firm Shares". Solely for the purpose of covering
over-allotments in the sale of the Firm Shares, the Company further proposes to
issue and sell to the Underwriters, at their option, up to an additional 315,000
shares of Common Stock (the "Option Shares") upon exercise of the over-allotment
option granted in Section 1 hereof. The Firm Shares and any Option Shares are
herein collectively referred to as the "Shares." You are acting as
representatives of the Underwriters and in such capacity are sometimes herein
referred to as the "Representatives."

         The Company hereby confirms as follows its agreement with each of the
Underwriters in connection with the proposed purchase of the Shares.

         1. Sale, Purchase and Delivery of Shares. On the basis of the
representations, warranties and agreements herein contained, and subject to the
terms and conditions herein set forth, the Company hereby agrees to sell to each
of the Underwriters and each of the Underwriters agrees, severally and not
jointly, to purchase from the Company, at a purchase price per share of $_______
(the "Purchase Price") the respective number of Firm Shares set forth opposite
the name of such Underwriter in Schedule I plus any additional number of Firm
Shares which such Underwriter may become obligated to purchase pursuant to the
provisions of Section 9 of this Agreement. The Representatives may by notice to
the Company amend Schedule I to add, eliminate or substitute names set forth
therein (other than to eliminate the names of a Representative) and to amend the
number of Firm Shares to be purchased by any firm or corporation listed thereon,
provided that the total number of Firm Shares listed on Schedule I shall equal
2,100,000.

                                       1


         The number of Firm Shares to be purchased by each Underwriter from the
Company shall bear the same ratio to the total number of Firm Shares to be sold
by the Company as the total number of Firm Shares to be purchased by such
Underwriter bears to the total number of Firm Shares to be purchased by the
Underwriters; provided, however, that the Representatives shall adjust the
number of Firm Shares to be purchased by each Underwriter from the Company as
necessary to eliminate fractional shares.

         In addition, on the basis of the representations, warranties and
agreements herein contained and subject to the terms and conditions herein set
forth, the Company hereby grants to the Underwriters, severally and not jointly,
an option to purchase all or any portion of the 315,000 Option Shares, and upon
the exercise of such option in accordance with this Section 1, the Company
hereby agrees to sell to the Underwriters, severally and not jointly, all or any
portion of the Option Shares at the same Purchase Price per share paid for the
Firm Shares; provided, that the purchase price per share for any Option Shares
purchased upon exercise of the over-allotment option shall be reduced by an
amount equal to any dividends or distributions declared by the Company and
payable on the Firm Shares but not payable on the Option Shares. If any Option
Shares are to be purchased, each Underwriter, severally and not jointly, agrees
to purchase from the Company that proportion (subject to adjustment as you may
determine to avoid fractional shares) of the number of Option Shares to be
purchased that the number of Firm Shares set forth opposite the name of such
Underwriter in Schedule I hereto (or such number increased as set forth in
Section 9 hereof) bears to 315,000. The option hereby granted (the "Option")
shall expire 30 days after the date upon which the Registration Statement (as
hereinafter defined) becomes effective and may be exercised only for the purpose
of covering over-allotments which may be made in connection with the offering
and distribution of the Firm Shares. The Option may be exercised in whole or in
part at any time (but not more than once) by you giving notice (confirmed in
writing) to the Company setting forth the number of Option Shares as to which
the Underwriters are exercising the Option and the time, date and place for
payment and delivery of certificates for such Option Shares. Such time and date
of payment and delivery for the Option Shares (the "Option Closing Date") shall
be determined by you, but shall not be earlier than 2 nor later than 5 full
business days after the exercise of such Option, nor in any event prior to the
Closing Date (as hereinafter defined). The Option Closing Date may be the same
as the Closing Date.

         Payment of the Purchase Price and delivery of certificates for the Firm
Shares shall be made at the offices of Stifel, Nicolaus & Company, Incorporated,
501 North Broadway, 9th Floor, St. Louis, Missouri 63102, or such other place as
shall be agreed to by you and the Company, at 10:00 a.m., St. Louis time, on
___________, 2005, or at such other time not more than 5 full business days
thereafter as the Company and you shall determine (the "Closing Date") or unless
postponed in accordance with the provisions of Section 9. If the Underwriters
exercise the option to purchase any or all of the Option Shares, payment of the
Purchase Price and delivery of certificates for such Option Shares shall be made
on the Option Closing Date at the offices of Stifel, Nicolaus & Company,
Incorporated, or at such other place as the Company and you shall determine.
Such payments shall be made to an account designated by the Company by wire
transfer or certified or bank cashier's check, in same day funds, in the amount
of the Purchase Price therefor, against delivery by or on behalf of the Company
to you for the respective accounts of the Underwriters of certificates for the
Shares to be purchased by them.

         The Agreement contained herein with respect to the timing of the
Closing Date and Option Closing Date is intended to, and does, constitute an
express agreement, as described in Rule 15c6-1(a) and (d) promulgated under the
1934 Act (as defined herein), for a settlement date other than three business
days after the date of the contract.

         Certificates for Shares to be purchased by the Underwriters shall be
delivered in fully registered form in such authorized denominations and
registered in such names as you shall request in writing not later than 12:00
noon, St. Louis time, two business days prior to the Closing Date and, if
applicable, the Option Closing Date. Certificates for Shares to be purchased by
the Underwriters shall be made available to you for inspection, checking and
packaging at such office as you may designate in writing not later than 1:00
p.m., St. Louis time, on the last business day prior to the Closing Date and, if
applicable, on the last business day prior to the Option Closing Date. If the
Representatives so elects, delivery of the Shares may be made by credit to the
accounts at The Depository Trust Company designated by the Representatives.

                                       2


         Time shall be of the essence, and delivery of the certificates for the
Shares at the time and place specified pursuant to this Agreement is a further
condition of the obligations of each Underwriter hereunder.

         2. Representations and Warranties. The Company represents and warrants
to, and agrees with, each of the Underwriters that:

         (a) Except as amended or superseded by subsequently filed reports, the
reports filed with the Securities and Exchange Commission (the "Commission") by
the Company under the Securities Exchange Act of 1934, as amended (the "1934
Act") and the rules and regulations thereunder (the "1934 Act Regulations") at
the time they were filed with the Commission, complied as to form with the
requirements of the 1934 Act and the 1934 Act Regulations and did not contain an
untrue statement of fact or omit to state any fact required to be stated therein
or necessary to make the statements therein, in light of the circumstances in
which they were made, not misleading.

         (b) The Company has prepared and filed with the Commission a
registration statement on Form S-3 (File No. 333-124502) for the registration of
the Shares under the Securities Act of 1933, as amended (the "1933 Act"),
including the related prospectus subject to completion, and one or more
amendments to such registration statement may have been so filed, in each case
in conformity with the requirements of the 1933 Act and the rules and
regulations promulgated thereunder (the "1933 Act Regulations"). The Company
meets the requirements for use of Form S-3. Copies of such registration
statement, including any amendments thereto, each Preliminary Prospectus (as
defined herein) contained therein and the exhibits, financial statements and
schedules to such registration statement, as finally amended and revised, have
heretofore been delivered by the Company to the Representatives. After the
execution of this Agreement, the Company will file with the Commission (i) if
such registration statement, as it may have been amended, has been declared by
the Commission to be effective under the 1933 Act, a prospectus in the form most
recently included in an amendment to such registration statement (or, if no such
amendment shall have been filed, in such registration statement), with such
changes or insertions as are required by Rule 430A of the 1933 Act Regulations
("Rule 430A") or permitted by Rule 424(b) of the 1933 Act Regulations ("Rule
424(b)") and as have been provided to and not objected to by the Representatives
prior to (or as are agreed to by the Representatives subsequent to) the
execution of this Agreement, or (ii) if such registration statement, as it may
have been amended, has not been declared by the Commission to be effective under
the 1933 Act, an amendment to such registration statement, including a form of
final prospectus, necessary to permit such registration statement to become
effective, a copy of which amendment has been furnished to and not objected to
by the Representatives prior to (or is agreed to by the Representatives
subsequent to) the execution of this Agreement. The Company will not file any
amendment to the registration statement or any amended Preliminary Prospectus or
any amendment thereto, of which you have not been previously furnished a copy or
to which you or counsel for the Underwriters shall reasonably object. As used in
this Agreement, the term "Registration Statement" means such registration
statement, as amended at the time when it was or is declared effective under the
1933 Act, including (1) all financial schedules and exhibits thereto (2) all
documents (or portions thereof) incorporated by reference therein filed under
the 1934 Act, and (3) any information omitted therefrom pursuant to Rule 430A
and included in the Prospectus (as hereinafter defined) (and, in the event any
post-effective amendment thereto or any Rule 462(b) Registration Statement
becomes effective prior to the Closing Date, the term "Registration Statement"
also means such registration statement as so amended or such Rule 462(b)
Registration Statement, as the case may be); the term "Rule 462(b) Registration
Statement" means a registration statement and any amendments thereto filed
pursuant to Rule 462(b) of the 1933 Act Regulations relating to the offering
covered by the Registration Statement; the term "Preliminary Prospectus" means
each prospectus subject to completion filed with such registration statement or
any amendment thereto, including all documents (or portions thereof)
incorporated by reference therein under the 1934 Act (including the prospectus
subject to completion, if any, included in the Registration Statement and each
prospectus filed pursuant to Rule 424(a) under the 1933 Act); and the term
"Prospectus" means the prospectus first filed with the Commission pursuant to
Rule 424(b)(1) or (4) or, if no prospectus is required to be filed pursuant to
Rule 424(b)(1) or (4), the prospectus included in the Registration Statement, in
each case including the financial schedules and all documents (or portions
thereof) incorporated by reference therein under the 1934 Act. The date on which
the Registration Statement becomes effective is hereinafter referred to as the
"Effective Date."

                                       3


         (c) Except as amended or superseded by a subsequently filed document,
the documents incorporated by reference in the Preliminary Prospectus or
Prospectus or from which information is so incorporated by reference, when they
became effective or were filed with the Commission, as the case may be, complied
with the requirements of the 1934 Act and the 1934 Act Regulations and any
future documents incorporated by reference so filed, when they are filed, will
comply with the requirements of the 1934 Act and the 1934 Act Regulations; no
such incorporated document contained or will contain any untrue statement of
fact or omit to state any fact required to be stated therein or necessary to
make the statements therein not misleading, and when read together and with the
other information in the Preliminary Prospectus or Prospectus, as the case may
be, at the time the Registration Statement became or becomes effective and at
the Closing Date and any Option Closing Date, did not or will not, as the case
may be, contain an untrue statement of fact or omit to state any fact required
to be stated therein or necessary to make the statements therein, in light of
the circumstances under which they were made, not misleading.

         (d) No order preventing or suspending the effectiveness of the
Registration Statement or preventing or suspending the use of any Preliminary
Prospectus or the Prospectus or suspending the qualification or registration of
the Shares for offering or sale in any jurisdiction has been issued by the
Commission, any state or other jurisdiction or other regulatory body nor has the
Commission, any state or other jurisdiction or other regulatory body, to the
knowledge of the Company, threatened to issue such an order or instituted
proceedings for such purpose. Each Preliminary Prospectus, at the time of filing
thereof, (i) complied with the requirements of the 1933 Act and the 1933 Act
Regulations and (ii) did not contain an untrue statement of fact or omit to
state any fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading; provided, however, that this representation and warranty does not
apply to statements or omissions made in reliance upon and in conformity with
information furnished in writing to the Company by you expressly for inclusion
in the Prospectus beneath the heading "Underwriting" (such information referred
to herein as the "Underwriters' Information"). Each Preliminary Prospectus and
the Prospectus will be identical to the electronically transmitted copies
thereof filed with the Commission pursuant to its EDGAR system, except to the
extent permitted by Regulation S-T.

         (e) The Registration Statement has been declared effective under the
1933 Act, and no post-effective amendment to the Registration Statement has been
filed with the Commission as of the date of this Agreement. At the Effective
Date and at all times subsequent thereto, up to and including the Closing Date
and, if applicable, the Option Closing Date, the Registration Statement and any
post-effective amendment thereto (i) complied and will comply in all material
respects with the requirements of the 1933 Act and the 1933 Act Regulations and
(ii) did not and will not contain an untrue statement of a material fact or omit
to state any material fact required to be stated therein or necessary to make
the statements therein not misleading; provided, however, that this
representation and warranty does not apply to Underwriters' Information. At the
Effective Date and at all times when the Prospectus is required to be delivered
in connection with offers and sales of Shares, including, without limitation,
the Closing Date and, if applicable, the Option Closing Date, the Prospectus, as
amended or supplemented, (1) complied and will comply in all material respects
with the requirements of the 1933 Act and the 1933 Act Regulations and (2) did
not contain and will not contain an untrue statement of a material fact or omit
to state any material fact required to be stated therein or necessary to make
the statements therein, in light of the circumstances under which they were
made, not misleading; provided, however, that this representation and warranty
does not apply to Underwriters' Information. The Registration Statement will be
identical to the electronically transmitted copy thereof filed with the
Commission pursuant to its EDGAR system, except to the extent permitted by
Regulation S-T.

                                       4


         (f) The Company is duly organized, validly existing and in good
standing under the laws of the State of Oklahoma, with full corporate and other
power and authority to own, lease and operate its properties and conduct its
business as described in and contemplated by the Registration Statement and the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus) and as currently being conducted and is duly registered
as a financial holding company under the Bank Holding Company Act of 1956, as
amended (the "BHC Act").

         (g) The Company has 17 direct or indirect subsidiaries. Such
subsidiaries are listed on Exhibit A attached hereto and incorporated herein by
this reference (the "Subsidiaries"). The Company does not own or control,
directly or indirectly, more than 5% of any class of equity security of any
corporation, association or other entity other than the Subsidiaries. Each
Subsidiary is a national banking association, federal savings bank, business
trust, statutory trust or corporation duly incorporated or organized (as the
case may be), validly existing and in good standing under the laws of its
respective jurisdiction of incorporation or organization (as the case may be).
Each such Subsidiary has full corporate and other power and authority to own,
lease and operate its properties and to conduct its business as described in and
contemplated by the Registration Statement and the Prospectus (or, if the
Prospectus is not in existence, the most recent Preliminary Prospectus) and as
currently being conducted. The deposit accounts of Stillwater National Bank and
Trust Company, a national banking association ("Stillwater National Bank") and
SNB Bank of Wichita, a federal savings bank ("SNB Wichita;" and together with
Stillwater National Bank, the "Banks") are insured by the Bank Insurance Fund
administered by the Federal Deposit Insurance Corporation (the "FDIC") up to the
maximum amount provided by law, except to the extent the Prospectus discloses
such deposit accounts are insured by the Savings Association Insurance Fund
administered by the FDIC and to such extent the deposit accounts are so insured
up to the maximum amount provided by law; and no proceedings for the
modification, termination or revocation of any such insurance are pending or, to
the knowledge of the Company, threatened. Stillwater National Bank is a member
of the Federal Reserve System, and no proceedings for the termination or
revocation of such membership are pending or, to the knowledge of the Company,
threatened.

         (h) The Company and each of the Subsidiaries is duly qualified to
transact business as a foreign corporation and is in good standing in each other
jurisdiction in which it owns or leases property or conducts its business so as
to require such qualification and in which the failure to so qualify would,
individually or in the aggregate, have a material adverse effect on the
condition (financial or otherwise), earnings, business, prospects or results of
operations of the Company and the Subsidiaries on a consolidated basis. All of
the issued and outstanding shares of capital stock of the Subsidiaries (i) have
been duly authorized and are validly issued, (ii) are fully paid and
nonassessable except to the extent such shares may be deemed assessable under 12
U.S.C. Section 55 or 12 U.S.C. Section 1831o. Except as disclosed in the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus), all of the issued and outstanding shares of capital
stock of the Bank are directly owned by the Company free and clear of any
security interest, mortgage, pledge, lien, encumbrance, restriction upon voting
or transfer, preemptive rights, claim or equity. Except as disclosed in the
Prospectus, there are no outstanding rights, warrants or options to acquire or
instruments convertible into or exchangeable for any capital stock or equity
securities of the Subsidiaries, except for preemptive rights under the National
Bank Act.

                                       5


         (i) The capital stock of the Company conforms to the description
thereof contained in the Prospectus or, if the Prospectus is not in existence,
the most recent Preliminary Prospectus. The outstanding shares of capital stock
of the Company have been duly authorized and validly issued and are fully paid
and nonassessable, and no such shares were issued in violation of the preemptive
or similar rights of any security holder of the Company; no person has any
preemptive or similar right to purchase any shares of capital stock or equity
securities of the Company. Except as disclosed in the Prospectus (or, if the
Prospectus is not in existence, the most recent Preliminary Prospectus), there
are no outstanding rights, options or warrants to acquire any securities of the
Company other than options issued under the Company's 1994 Stock Option Plan and
the Company's 1999 Stock Option Plan, and there are no outstanding securities
convertible into or exchangeable for any such securities, and no restrictions
upon the voting or transfer of any capital stock of the Company pursuant to the
Company's corporate charter or by-laws or any agreement or other instrument to
which the Company is a party or by which it is bound.

         (j) The Company has all requisite power and authority to issue, sell
and deliver the Shares to be sold by the Company in accordance with and upon the
terms and conditions set forth in this Agreement and in the Registration
Statement and the Prospectus (or, if the Prospectus is not in existence, the
most recent Preliminary Prospectus). All corporate action required to be taken
by the Company for the authorization, issuance, sale and delivery of the Shares
to be sold by the Company has been validly and sufficiently taken. The Shares to
be sold by the Company, when delivered and paid for in accordance with this
Agreement, will be duly and validly issued and outstanding, fully paid and
nonassessable, and will conform to the description thereof in the Registration
Statement and the Prospectus (or, if the Prospectus is not in existence, the
most recent Preliminary Prospectus); and will not be issued in violation of or
subject to any preemptive or similar rights. None of the Shares, immediately
prior to delivery, will be subject to any security interest, lien, mortgage,
pledge, encumbrance, restriction upon voting or transfer, preemptive rights,
claim, equity or other defect.

         (k) The Company and each of the Subsidiaries (i) are in compliance with
Federal, state, local and foreign laws, statutes, ordinances, rules, regulations
and decrees including, but not limited to, those of self-regulatory
organizations, the BHC Act, the Bank Secrecy Act, the Gramm-Leach-Bliley Act,
International Money Laundering Abatement and Anti-Terrorist Financing Act of
2001, the USA PATRIOT Act of 2001 and those of the Board of Governors of the
Federal Reserve System (the "Federal Reserve"), the Oklahoma Banking
Commissioner ("OBC"), Oklahoma Banking Department ("OBD"), the Office of the
State Bank Commissioner or the State of Kansas ("SBCK"), the Texas Department of
Banking ("TDB"), the Federal Home Loan Mortgage Corporation ("FHLMC"), the
Federal Housing Administration (the "FHA"), the Federal National Mortgage
Association (the "FNMA"), the United States Department of Housing and Urban
Development ("HUD"), the Office of the Comptroller of Currency (the "OCC"), the
U.S. Department of Agriculture as Rural Housing and Community Development
Service Approved Center (the "USDA"), and the United States Department of
Veterans Affairs (the "UA") (collectively, "Laws"), applicable to their
businesses or their employees, including, without limitation, licensing and
certification Laws covering any aspect of the businesses of the Company or any
of the Subsidiaries, and neither the Company nor any of the Subsidiaries has
received any notification asserting any failure to comply with or violation of
any such Laws; (ii) are not, nor are any of their respective affiliates, subject
to a "statutory disability" as defined in Section 3(a)(39) of the 1934 Act, and
(iii) have filed all reports, registrations and statements, together with any
amendments required to be made with respect thereto, that were required to be
filed (A) with the Federal Reserve, HUD, the FHA, FHLMC, FNMA, FDIC, OCC, SBCK,
USDA, UA, TDB, OBC and OBD and (B) under any applicable statute, rule,
regulation, law or order, with any applicable governmental authority or
self-regulatory organization with jurisdiction over any of the activities of the
Company or the Subsidiaries, including reports relating to escheatment of funds
(collectively, the "Company Regulatory Reports"), and have paid all fees in
connection therewith, except where the failure to make any such filing would not
have a material adverse effect on the condition (financial or otherwise),
earnings, affairs, business, prospects, or results of operations of the Company
and the Subsidiaries on a consolidated basis. As of their respective dates, the
Company Regulatory Reports complied in all respects with the applicable
statutes, rules, regulations, laws and orders enforced or promulgated by the
governmental authority or self-regulatory organization with which they were
filed, except in all such cases described in clauses (i) - (iii) of the
preceding sentence where such noncompliance or violation would not have a
material adverse effect on the condition (financial or otherwise), earnings,
affairs, business, prospects, or results of operations of the Company and the
Subsidiaries on a consolidated basis, and did not contain any untrue statement
of a material fact or omit to state a material fact required to be stated
therein or necessary to make the statement therein, in the light of the
circumstances under which they were made, not misleading.

                                       6


         (l) The activities of the Company and the Subsidiaries are permitted
under applicable Federal and state banking laws and regulations. The Company has
all necessary approvals, including the approval of HUD, the FHA, FHLMC, FNMA,
SBCK, OBC, OBD, TDB, OCC, USDA, UA, and the Federal Reserve, as applicable, to
own the capital stock of its subsidiaries. Neither the Company nor any of its
Subsidiaries, nor, to the Company's knowledge, any of their respective
directors, officers or trustee, is party or subject to, or has received any
notice or advice that any of them may become party or subject to, any
investigation with respect to, any cease-and-desist order, agreement, memorandum
of understanding, commitment letter, directive or other regulatory enforcement
action, proceeding or order with or by, or has been a recipient of any
supervisory letter from, or has adopted any board resolutions at the request of,
any regulator (including HUD, the FHA, FHLMC, FNMA, SBCK, TDB, OBC, OBD, OCC,
USDA, UA, , the Federal Reserve, the FDIC, or any other federal or state agency
charged with the supervision or regulation of depository institutions, banks, or
financial holding companies, or engaged in the insurance of depository
institution deposits, or any court, administrative agency or commission or other
governmental agency, authority or instrumentality having supervisory or
regulatory authority with respect to the Company or any of its Subsidiaries
(each, a "Regulator")) that imposes any restrictions or requirements not
generally applicable to entities of the same type as the Company and the
Subsidiaries or currently restricts in any material respect the conduct of their
business or that in any material manner relates to their capital adequacy, their
credit policies, their ability or authority to pay dividends or make
distributions to their shareholders or make payments of principal or interest on
their debt obligations, their management or their business (each a "Regulatory
Agreement"), nor has the Company or any of its Subsidiaries been advised by any
Regulator that it is considering issuing or requesting any such Regulatory
Agreement, except for Regulatory Agreements that would not, individually or in
the aggregate, have a material adverse effect on the condition (financial or
otherwise), earnings, affairs, business, prospects, or results of operations of
the Company and the Subsidiaries on a consolidated basis. There is no material
unresolved violation, criticism or exception by any Regulator with respect to
any report or statement relating to any examinations of the Company or any of
its Subsidiaries.

         (m) The Company and the Subsidiaries have all material permits,
easements, consents, licenses, grants, certificates, orders, approvals,
franchises and other governmental and regulatory authorizations from all
appropriate federal, state, local or other public authorities ("Permits") as are
necessary to own or lease their properties and conduct their businesses in the
manner described in and contemplated by the Registration Statement and the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus) and as currently being conducted in all material
respects. All such Permits are in full force and effect and each of the Company
and the Subsidiaries are in all material respects complying therewith, and no
event has occurred that allows, or after notice or lapse of time would allow,
revocation or termination thereof or will result in any other material
impairment of the rights of the holder of any such Permit. Such Permits contain
no restrictions that would materially impair the ability of the Company or the
Subsidiaries to conduct their businesses in the manner consistent with their
past practices. Neither the Company nor any of the Subsidiaries has received
notice or otherwise has knowledge of any proceeding or action relating to the
revocation or modification of any such Permit.

                                       7


         (n) Neither of the Company nor any of the Subsidiaries is in breach or
violation of its corporate charter, by-laws or other governing documents.
Neither of the Company nor any of the Subsidiaries is, and to the knowledge of
the Company no other party is, in violation, breach or default (with or without
notice or lapse of time or both) in the performance or observance of any term,
covenant, agreement, obligation, representation, warranty or condition contained
in (i) any contract, indenture, mortgage, deed of trust, loan or credit
agreement, note, lease, franchise, license, Permit or any other agreement or
instrument to which it is a party or by which it or any of its properties may be
bound, which such breach, violation or default could have material adverse
consequences to the Company on a consolidated basis, and to the knowledge of the
Company, no other party has asserted that the Company or any of the Subsidiaries
is in such violation, breach or default (provided that the foregoing shall not
apply to defaults by borrowers from either of the Banks), or (ii) any order,
decree, judgment, rule or regulation, of any court, arbitrator, government, or
governmental agency or instrumentality, domestic or foreign, having jurisdiction
over the Company or the Subsidiaries or any of their respective properties the
breach, violation or default of which could have a material adverse effect on
the condition (financial or otherwise), earnings, affairs, business, prospects,
or results of operations of the Company and the Subsidiaries on a consolidated
basis.

         (o) The execution, delivery and performance of this Agreement and the
consummation of the transactions contemplated herein, in the Registration
Statement and in the Prospectus (or, if the Prospectus in not in existence, the
most recent Preliminary Prospectus) do not and will not conflict with, result in
the creation or imposition of any material lien, claim, charge, encumbrance or
restriction upon any property or assets of the Company or the Subsidiaries or
the Shares to be sold by the Company pursuant to, constitute a breach or
violation of, or constitute a default under, with or without notice or lapse of
time or both, any of the terms, provisions or conditions of the charter, by-laws
or any other governing document of the Company or the Subsidiaries, any
contract, indenture, mortgage, deed of trust, loan or credit agreement, note,
lease, franchise, license, Permit or any other agreement or instrument to which
the Company or any of the Subsidiaries is a party or by which any of them or any
of their respective properties may be bound or any order, decree, judgment, rule
or regulation of any court, arbitrator, government, or governmental agency or
instrumentality, domestic or foreign, having jurisdiction over the Company or
the Subsidiaries or any of their respective properties which conflict, creation,
imposition, breach, violation or default would have either singly or in the
aggregate have a material adverse effect on the condition (financial or
otherwise), earnings, affairs, business, prospects or results of operations of
the Company and the Subsidiaries on a consolidated basis. No authorization,
approval, consent or order of, or filing, registration or qualification with,
any person (including, without limitation, any court, governmental body or
authority) is required in connection with the transactions contemplated by this
Agreement, the Registration Statement and the Prospectus (or such Preliminary
Prospectus), except such as have been obtained under the 1933 Act and from the
Nasdaq National Market relating to the approval for quotation of the additional
shares of Common Stock, and such as may be required under state securities laws
or Interpretations or Rules of the National Association of Securities Dealers,
Inc. ("NASD") in connection with the purchase and distribution of the Shares by
the Underwriters.

                                       8


         (p) The Company has all requisite corporate power and authority to
enter into this Agreement and this Agreement has been duly and validly
authorized, executed and delivered by the Company and constitutes the legal,
valid and binding agreement of the Company, enforceable in accordance with its
terms, except as the enforcement thereof may be limited by general principles of
equity and by bankruptcy or other laws relating to or affecting creditors'
rights generally.

         (q) The Company and the Subsidiaries have good and marketable title in
fee simple to all real property and good title to all personal property owned by
them and material to their business on a consolidated basis, in each case free
and clear of all security interests, liens, mortgages, pledges, encumbrances,
restrictions, claims, equities and other defects except such as are referred to
in the Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus) or such as do not materially affect the value of such
property in the aggregate and do not materially interfere with the use made or
proposed to be made of such property; and all of the leases under which the
Company or any of the Subsidiaries holds real or personal property are valid,
existing and enforceable leases and in full force and effect with such
exceptions as are not material and do not materially interfere with the use made
or proposed to be made of such real or personal property, and neither the
Company nor any of the Subsidiaries is in default in any material respect of any
of the terms or provisions of any leases.

         (r) Ernst & Young LLP (the "Accountant"), who have audited the
consolidated financial statements of the Company and the Subsidiaries, including
the notes thereto, included by incorporation by reference or otherwise in the
Registration Statement and Prospectus, are independent public accountants with
respect to the Company and the Subsidiaries, as required by the 1933 Act and the
1933 Act Regulations. The Company has not engaged the Accountant to provide any
services to the Company that are impermissible under the 1934 Act, except as
permissible under the 1934 Act at the time such services were provided. All such
services had been approved by the Audit Committee of the Company's Board of
Directors as required by the 1934 Act.

         (s) The consolidated financial statements, including the notes thereto,
included by incorporation by reference or otherwise in the Registration
Statement and the Prospectus (or, if the Prospectus is not in existence, the
most recent Preliminary Prospectus) with respect to the Company and its
Subsidiaries comply in all material respects with the 1933 Act and the 1933 Act
Regulations and present fairly the consolidated financial position of the
Company and its Subsidiaries as of the dates indicated and the consolidated
results of operations, cash flows, shareholders' equity and comprehensive income
of the Company and its Subsidiaries for the periods specified have been prepared
in conformity with generally accepted accounting principles applied on a
consistent basis. The selected and summary consolidated financial data
concerning the Company and its Subsidiaries included or incorporated by
reference in the Registration Statement and the Prospectus (or such Preliminary
Prospectus) comply in all material respects with the 1933 Act and the 1933 Act
Regulations, present fairly the information set forth therein, and have been
compiled on a basis consistent with that of the consolidated financial
statements of the Company and its Subsidiaries in the Registration Statement and
the Prospectus (or such Preliminary Prospectus). The other financial,
statistical and numerical information included in the Registration Statement and
the Prospectus (or such Preliminary Prospectus) comply in all material respects
with the 1933 Act and the 1933 Act Regulations, present fairly the information
shown therein, and to the extent applicable have been compiled on a basis
consistent with the consolidated financial statements of the Company and its
Subsidiaries included in the Registration Statement and the Prospectus (or such
Preliminary Prospectus). There are no pro forma financial statements or other
pro forma financial information required to be included or incorporated by
reference in the Registration Statement or the Prospectus. No other financial
statements or schedules of the Company are required by the 1933 Act or the 1933
Act Regulations, or the 1934 Act or the 1934 Act Regulations to be included or
incorporated by reference in the Registration Statement or the Prospectus.

                                       9


         (t) The Company and each of the Subsidiaries maintains a system of
internal accounting controls sufficient to provide reasonable assurance (i)
regarding the reliability of financial reporting and the preparation of
financial statements for external purposes in accordance in generally accepted
accounting principles and (ii) that: (A) transactions are executed in accordance
with management's general or specific authorizations; (B) transactions are
recorded as necessary to permit preparation of financial statements in
conformity with generally accepted accounting principles and to maintain
accountability for assets; (C) access to assets is permitted only in accordance
with management's general or specific authorization; and (D) the recorded
accounts for assets is compared with the existing assets at reasonable intervals
and appropriate action is taken with respect to any differences. The
certifications of the Company's Chief Executive Officer and Chief Financial
Officer filed as exhibits to the Company's annual report on Form 10-K for the
fiscal year ended December 31, 2004, pursuant to Sections 302 and 906 of the
Sarbanes-Oxley Act, were accurate in all material respects as of the date such
certifications were made, and to the knowledge of the Company, such
certifications are accurate in all material respects as of the date hereof.

         (u) Based on the evaluation of its disclosure controls and procedures,
the Company is not aware of (i) any material weakness in the design or operation
of internal control over financial reporting that are reasonably likely to
adversely affect the Company's ability to record, process, summarize and report
financial information or (ii) any fraud, whether or not material, that involves
management or other employees who have a significant role in the Company's
internal control over financial reporting. There have been no changes in
internal control over financial reporting during the Company's most recent
fiscal quarter that have materially affected or are reasonably likely to
materially affect the Company's internal control over financial reporting.

         (v) Since the respective dates as of which information is given in the
Registration Statement and the Prospectus (or, if the Prospectus is not in
existence, the most recent Preliminary Prospectus), except as otherwise stated
therein:

                  (i) neither the Company nor any of its Subsidiaries has
         sustained any loss or interference with its business from fire,
         explosion, flood or other calamity, whether or not covered by
         insurance, or from any labor dispute or court or governmental action,
         order or decree which is material to the condition (financial or
         otherwise), earnings, business, prospects or results of operations of
         the Company and the Subsidiaries on a consolidated basis;

                  (ii) there has not been any material adverse change in, or any
         development which is likely to have a material adverse effect on, the
         condition (financial or otherwise), earnings, business, prospects or
         results of operations of the Company and the Subsidiaries on a
         consolidated basis, whether or not arising in the ordinary course of
         business;

                  (iii) neither the Company nor any of its Subsidiaries has
         incurred any liabilities or obligations, direct or contingent, or
         entered into any material transactions, other than in the ordinary
         course of business which is material to the condition (financial or
         otherwise), earnings, business, prospects or results of operations of
         the Company and the Subsidiaries on a consolidated basis;

                  (iv) the Company has not declared or paid any dividend, and
         neither the Company nor any of its Subsidiaries has become delinquent
         in the payment of principal or interest on any outstanding borrowings;
         and

                  (v) there has not been any change in the capital stock (except
         for the exercise of employee stock options issued under the Company's
         1994 Stock Option Plan or the Company's 1999 Stock Option Plan, and
         previously disclosed as outstanding options, stock issued pursuant to
         the Company's Employee Stock Purchase Plan and stock issued pursuant to
         the Company's Dividend Reinvestment Plan), long-term debt, obligations
         under capital leases or, other than in the ordinary course of business,
         short-term borrowings of the Company or the Subsidiaries.

                                       10


         (w) The Company and its Subsidiaries maintain insurance of the types
and in the amounts generally deemed adequate for its business, including, but
not limited to, directors' and officers' insurance, insurance covering real and
personal property owned or leased by the Company and its Subsidiaries against
theft, damage, destruction, acts of vandalism and all other risks customarily
insured against, all of which insurance is in full force and effect. Neither the
Company nor any of its Subsidiaries has been refused any insurance coverage
sought or applied for, and the Company has no reason to believe that it and its
Subsidiaries will not be able to renew their existing insurance coverage as and
when such coverage expires or to obtain similar coverage from similar insurers
as may be necessary to continue its business at a cost that would not have a
material adverse effect on the condition (financial or otherwise), earnings,
affairs, business, prospects or results of operations of the Company and the
Subsidiaries on a consolidated basis.

         (x) Except as set forth in the Registration Statement and the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus), no charge, investigation, action, suit or proceeding is
pending or, to the knowledge of the Company, threatened, against or affecting
the Company or the Subsidiaries or any of their respective properties before or
by any court or any regulatory, administrative or governmental official,
commission, board, agency or other authority or body, or any arbitrator, and
there is no factual basis for any such charge, investigation, action, suit or
proceeding wherein an unfavorable decision, ruling or finding could reasonably
be expected to have a material adverse effect on the consummation of this
Agreement or the transactions contemplated herein or the condition (financial or
otherwise), earnings, affairs, business, prospects or results of operations of
the Company and the Subsidiaries on a consolidated basis or which is required to
be disclosed in the Registration Statement or the Prospectus (or such
Preliminary Prospectus) and is not so disclosed.

         (y) There are no contracts or other documents required to be filed as
exhibits to the Registration Statement by the 1933 Act or the 1933 Act
Regulations which have not been filed as exhibits or incorporated by reference
to the Registration Statement, or that are required to be summarized in the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus) that are not so summarized.

         (z) The Company has not taken, directly or indirectly, any action
designed to result in or which has constituted or which might cause or result in
stabilization or manipulation of the price of any security of the Company to
facilitate the sale or resale of the Shares, and the Company is not aware of any
such action taken or to be taken by any affiliate of the Company. The Company
acknowledges that the Underwriters may engage in passive market-making
transactions in the Shares on the Nasdaq National Market in accordance with
Regulation M under the 1934 Act.

         (aa) The Company and the Subsidiaries own, or possess adequate rights
to use, all patents, copyrights, trademarks, service marks, trade names and
other rights necessary to conduct the businesses now conducted by them in all
material respects or as described in the Prospectus (or, if the Prospectus is
not in existence, the most recent Preliminary Prospectus) and neither the
Company nor any of the Subsidiaries has received any notice of infringement or
conflict with asserted rights of others with respect to any patents, copyrights,
trademarks, service marks, trade names or other rights, which, individually or
in the aggregate, if the subject of an unfavorable decision, ruling or finding,
would have a material adverse effect on the condition (financial or otherwise),
earnings, affairs, business, prospects or results of operations of the Company
and the Subsidiaries on a consolidated basis, and the Company does not know of
any basis for any such infringement or conflict.

                                       11


         (bb) No labor dispute involving the Company or the Subsidiaries exists
or, to the knowledge of the Company, is imminent which might be expected to have
a material adverse effect on the condition (financial or otherwise), earnings,
affairs, business, prospects or results of operations of the Company and the
Subsidiaries on a consolidated basis or which is required to be disclosed in the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus). Neither the Company nor any of the Subsidiaries has
received notice of any existing or threatened labor dispute by the employees of
any of its principal suppliers, customers or contractors which might be expected
to have a material adverse effect on the condition (financial or otherwise),
earnings, affairs, business, prospects or results of operations of the Company
and the Subsidiaries on a consolidated basis.

         (cc) The Company and the Subsidiaries have timely and properly prepared
and filed all necessary federal, state, local and foreign tax returns which are
required to be filed and have paid all taxes shown as due thereon and have paid
all other taxes and assessments to the extent that the same shall have become
due, except such as are being contested in good faith or where the failure to so
timely and properly prepare and file would not have a material adverse effect on
the condition (financial or otherwise), earnings, affairs, business, prospects
or results of operations of the Company and the Subsidiaries on a consolidated
basis. The Company has no knowledge of any tax deficiency which has been or
might be assessed against the Company or the Subsidiaries which, if the subject
of an unfavorable decision, ruling or finding, would have a material adverse
effect on the condition (financial or otherwise), earnings, affairs, business,
prospects or results of operations of the Company and the Subsidiaries on a
consolidated basis.

         (dd) The Company is in compliance with all material respects with all
presently applicable provisions of the Employee Retirement Income Security Act
of 1974, as amended, including the regulations and published interpretations
thereunder ("ERISA"); the Company has no "pension plan" (as defined in ERISA)
for which it would have any liability; the Company has not incurred and does not
expect to incur liability under (i) Title IV of ERISA with respect to
termination of, or withdrawal from, any "pension plan" or (ii) Sections 412 or
4971 of the Internal Revenue Code of 1986, as amended, including the regulations
and published interpretations thereunder (the "Code"); and each "pension plan"
for which the Company would have any liability that is intended to be qualified
under Section 401(a) of the Code is so qualified in all material respects and
nothing has occurred, whether by action or by failure to act, that would cause
the loss of such qualification.

         (ee) Each of the material contracts, agreements and instruments
described or referred to in the Registration Statement or the Prospectus (or, if
the Prospectus is not in existence, the most recent Preliminary Prospectus) and
each contract, agreement and instrument filed as an exhibit to the Registration
Statement or incorporated by reference into the Registration Statement or the
Prospectus (or, if the Prospectus is not in existence, the most recent
Preliminary Prospectus), is in full force and effect and is the legal, valid and
binding agreement of the Company or the Subsidiaries, enforceable in accordance
with its terms, except as the enforcement thereof may be limited by general
principles of equity and by bankruptcy or other laws relating to or affecting
creditors' rights generally. Except as disclosed in the Prospectus (or such
Preliminary Prospectus), to the knowledge of the Company, no other party to any
such agreement is (with or without notice or lapse of time or both) in breach or
default in any material respect thereunder; provided, however, that the
foregoing shall not apply to defaults by borrowers from the Banks.

         (ff) Except as described in the Registration Statement or Prospectus
(or, if the Prospectus is not in existence, the most recent Preliminary
Prospectus), neither the Company nor any of the Subsidiaries has sent or
received any notice indicating the termination of or intention to terminate any
of the material contracts, agreements or instruments described or referred to in
the Registration Statement or the Prospectus (or, if the Prospectus is not in
existence, the most recent Preliminary Prospectus), or filed as an exhibit to
the Registration Statement or any of the documents incorporated by reference
into the Registration Statement or the Prospectus (or, if the Prospectus is not
in existence, the most recent Preliminary Prospectus), the termination of which
would have a material adverse effect on the condition (financial or otherwise),
earnings, affairs, business, prospects or results of operations of the Company
and the Subsidiaries on a consolidated basis, and no such termination has been
threatened by the Company, any Subsidiary or any other party to such contract or
agreement, except as would not have material adverse effect on the condition
(financial or otherwise), earnings, affairs, business, prospects or results of
operations of the Company and the Subsidiaries on a consolidated basis.

                                       12


         (gg) No relationship, direct or indirect, exists between or among the
Company or the Subsidiaries, on the one hand, and the directors, officers,
trustees, stockholders, customers or suppliers of the Company or the
Subsidiaries, on the other hand, which is required to be described in the
Registration Statement and the Prospectus (or, if the Prospectus is not in
existence, the most recent Preliminary Prospectus) which is not adequately
described therein.

         (hh) No person has the right to request or require the Company or the
Subsidiaries to register any securities for offering and sale under the 1933 Act
by reason of the filing of the Registration Statement with the Commission, the
issuance of the Shares to be sold by the Company or the sale of the Shares.

         (ii) Additional shares of Common Stock have been approved for quotation
on the Nasdaq National Market subject to official notice of issuance, and will
be quoted on a "when issued" basis prior to the Closing, such that all of the
Shares are quoted on, or have been approved for quotation (subject to official
notice of issuance) on, the Nasdaq National Market.

         (jj) Except as described in the Prospectus (or, if the Prospectus is
not in existence, the most recent Preliminary Prospectus), there are no
contractual encumbrances or restrictions or legal restrictions, on the ability
of the Subsidiaries (A) to pay dividends or make any other distributions on its
capital stock or to pay any indebtedness owed to the Company, (B) to make any
loans or advances to, or investments in, the Company or (C) to transfer any of
its property or assets to the Company.

         (kk) Neither the Company nor any of the Subsidiaries is, nor will be
after receipt of payment for the Shares, an "investment company" or any entity
"controlled" by an "investment company" within the meaning of such term under
the Investment Company Act of 1940, as amended (the "Investment Company Act"),
and the rules and regulations of the Commission thereunder. The Company and the
Subsidiaries will conduct their business in a manner so that they will not
become subject to the Investment Company Act.

         (ll) The Company has not distributed and will not distribute prior to
the Closing Date any offering material in connection with the offering of the
Shares, other than a Preliminary Prospectus, the Prospectus, the Registration
Statement and the other materials permitted by the 1933 Act and the 1933 Act
Regulations and reviewed by the Representatives.

         (mm) There are no affiliations or associations between any member of
the NASD and any of the Company's officers, directors or 5% or greater security
holders.

         (nn) Neither the Company nor any of the Banks has received any notice
of non-compliance with the applicable provisions of the Community Reinvestment
Act ("CRA") and the regulations promulgated thereunder, and each of the Banks
has received a CRA rating of satisfactory or better from the FDIC or other
applicable governmental authority. The Company knows of no facts or
circumstances that would cause any of the Banks to fail to comply with such
provisions or cause the CRA rating of either of the Banks to fall below
satisfactory.

                                       13


         (oo) To the best knowledge of the Company, each of the Company and the
Subsidiaries has properly administered all accounts for which any of them acts
as a fiduciary, including, but not limited to, accounts for which any of them
serves as a trustee, agent, custodian, personal representative, guardian,
conservator or investment adviser, in accordance with the terms of the governing
documents and applicable state and Federal law and regulation and common law,
except where the failure to have so administered or to be in compliance would
not have a material adverse effect on the condition (financial or otherwise),
earnings, affairs, business, prospects, or results of operations of the Company
and the Subsidiaries on a consolidated basis. None of the Company, the
Subsidiaries or any of their respective directors, officers or employees has
committed any material breach of trust with respect to any such fiduciary
account, and the accountings for each such fiduciary account are true and
correct in all material respects and accurately reflect the assets of such
fiduciary account in all material respects.

         (pp) Each agreement under which the Company and the Subsidiaries
provides investment advisory service to any person that is subject to Section 15
of the Investment Company Act has been fully approved at all times in compliance
in all material respects with Section 15 of the Investment Company Act and
applicable Law. Except where the failure, either individually or in the
aggregate, would not have a material adverse effect on the condition (financial
or otherwise), earnings, affairs, business, prospects, or results of operations
of the Company and the Subsidiaries on a consolidated basis, each such
investment advisory contract has been performed in accordance with the
Investment Company Act and any other applicable Law.

         (qq) The information contained in the Registration Statement and the
Prospectus regarding the Company's expectations, plans and intentions, and any
other information that constitutes "forward-looking" information within the
meaning of the 1933 Act and the 1934 Act, were made by the Company and its
management on a reasonable basis and in the exercise of their reasonable
judgment, and reflect the Company's and its management's good faith belief or
estimate of the matters described therein.

         (rr) Any certificate signed by any officer of the Company and delivered
to the Representatives or counsel for the Underwriters in connection with the
offering of the Shares contemplated hereby shall be deemed a representation and
warranty by the Company made as of the date of such certificate (except to the
extent a date is specified in such representation or warranty, in which case
such representation or warranty shall be deemed made as of such date) to each
Underwriter and shall be deemed to be a part of this Section 2 and incorporated
herein by reference.

         (ss) The Company is in compliance in all material respects with the
applicable provisions of the Sarbanes-Oxley Act.

         3. Offering by the Underwriters. After the Registration Statement
becomes effective or, if the Registration Statement is already effective, after
this Agreement becomes effective, the Underwriters propose to offer the Firm
Shares for sale to the public upon the terms and conditions set forth in the
Prospectus. The Underwriters may from time to time thereafter reduce the public
offering price and change the other selling terms, provided the proceeds to the
Company shall not be reduced as a result of such reduction or change.

         The Underwriters may reserve and sell such of the Shares purchased by
the Underwriters as the Underwriters may elect to dealers chosen by them (the
"Selected Dealers") at the public offering price set forth in the Prospectus
less the applicable Selected Dealers' concessions set forth therein, for
re-offering by Selected Dealers to the public at the public offering price. The
Underwriters may allow, and Selected Dealers may re-allow, a concession set
forth in the Prospectus to certain other brokers and dealers.

                                       14


         4. Certain Covenants of the Company. The Company covenants with each of
the Underwriters as follows:

         (a) The Company shall use its best efforts to cause the Registration
Statement and any amendments thereto, if not effective at the time of execution
of this Agreement, to become effective as promptly as possible. If the
Registration Statement has become or becomes effective pursuant to Rule 430A and
information has been omitted therefrom in reliance on Rule 430A, then, the
Company will prepare and file in accordance with Rule 430A and Rule 424(b)
copies of the Prospectus or, if required by Rule 430A, a post-effective
amendment to the Registration Statement (including the Prospectus) containing
all information so omitted and will provide evidence satisfactory to the
Representatives of such timely filing.

         (b) The Company shall notify you immediately, and confirm such notice
in writing:

                  (i) when the Registration Statement, or any post-effective
         amendment to the Registration Statement, has become effective, or when
         the Prospectus or any supplement to the Prospectus or any amended
         Prospectus has been filed;

                  (ii) of the receipt of any comments or requests from the
         Commission relating in any way to the Registration Statement, any
         Preliminary Prospectus, the Prospectus, or any amendments or
         supplements to any of the aforementioned of any request of the
         Commission to amend or supplement the Registration Statement, any
         Preliminary Prospectus or the Prospectus or for additional information;
         and

                  (iii) of the issuance by the Commission or any state or other
         regulatory body of any stop order or other order suspending the
         effectiveness of the Registration Statement, preventing or suspending
         the use of any Preliminary Prospectus or the Prospectus, or suspending
         the qualification of any of the Shares for offering or sale in any
         jurisdiction or the institution or threat of institution of any
         proceedings for any of such purposes. The Company shall use its best
         efforts to prevent the issuance of any such stop order or of any other
         such order and if any such order is issued, to cause such order to be
         withdrawn or lifted as soon as possible.

         (c) The Company shall furnish to you, from time to time without charge,
as soon as available, as many copies as you may reasonably request of (i) the
registration statement as originally filed and of all amendments and supplements
thereto, in executed form, including exhibits, whether filed before or after the
Registration Statement becomes effective, (ii) all exhibits and documents
incorporated therein or filed therewith, (iii) all consents and certificates of
experts in executed form, (iv) each Preliminary Prospectus and all amendments
and supplements thereto, and (v) the Prospectus, and all amendments and
supplements thereto.

                                       15


         (d) During the time when a prospectus is required to be delivered under
the 1933 Act, the Company shall comply with the 1933 Act and the 1933 Act
Regulations and the 1934 Act and the 1934 Act Regulations so as to permit the
completion of the distribution of the Shares as contemplated herein and in the
Prospectus. The Company shall not file any amendment to the registration
statement as originally filed or to the Registration Statement and shall not
file any amendment thereto or make any amendment or supplement to any
Preliminary Prospectus or to the Prospectus and will not file any document under
the 1934 Act before the termination of the offering of the Shares by the
Underwriters if the document would be deemed to be incorporated by reference
into the Registration Statement or the Prospectus of which you shall not
previously have been advised in writing and provided a copy within a reasonable
time prior to the proposed filings thereof or to which you or your counsel shall
reasonably object. If it is necessary, in your reasonable opinion or in the
reasonable opinion of counsel for the Underwriters, to amend or supplement the
Registration Statement or the Prospectus in connection with the distribution of
the Shares, the Company shall forthwith amend or supplement the Registration
Statement or the Prospectus, as the case may be, by preparing and filing with
the Commission, and furnishing to you, such number of copies as you may
reasonably request of an amendment or amendments of, or a supplement or
supplements to, the Registration Statement or the Prospectus, as the case may be
(in form and substance reasonably satisfactory to you and to counsel for the
Underwriters). If any event shall occur as a result of which it is necessary to
amend or supplement the Prospectus to correct an untrue statement of fact or to
include any fact necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, or if for any reason
it is necessary at any time to amend or supplement the Prospectus to comply with
the 1933 Act and the 1933 Act Regulations, the Company shall, subject to the
second sentence of this subsection (d), forthwith amend or supplement the
Prospectus by preparing and filing with the Commission, and furnishing to you,
such number of copies as you may reasonably request of an amendment or
amendments of, or a supplement or supplements to, the Prospectus (in form and
substance satisfactory to you and to counsel for the Underwriters) so that, as
so amended or supplemented, the Prospectus shall not contain an untrue statement
of fact or omit to state any fact necessary to make the statements therein, in
light of the circumstances under which they were made, not misleading.

         (e) The Company shall cooperate with you and counsel for the
Underwriters in order to qualify the Shares for offering and sale under the
securities or blue sky laws of such jurisdictions as you may reasonably request
and shall continue such qualifications in effect so long as may be advisable for
distribution of the Shares; provided, however, that the Company shall not be
required to qualify to do business as a foreign corporation or file a general
consent to service of process in any jurisdiction in connection with the
foregoing. The Company shall file such statements and reports as may be required
by the laws of each jurisdiction in which the Shares have been qualified as
above. The Company will notify you immediately of, and confirm in writing, the
suspension of qualification of the Shares or threat thereof in any jurisdiction.

         (f) The Company shall make generally available to its security holders
in the manner contemplated by Rule 158 of the 1933 Act Regulations and furnish
to you as soon as practicable, but in any event not later than 16 months after
the Effective Date, a consolidated earnings statement of the Company conforming
with the requirements of Section 11(a) of the 1933 Act and Rule 158.

         (g) The Company shall use the proceeds from the sale of the Shares to
be sold by the Company hereunder in the manner specified in the Prospectus under
the caption "Use of Proceeds."

         (h) For 5 years from the Effective Date, the Company shall furnish to
the Representatives copies of all reports and communications (financial or
otherwise) furnished by the Company to the holders of the Common Stock as a
class, copies of all reports and financial statements filed with or furnished to
the Commission (other than portions for which confidential treatment has been
obtained from the Commission) or with any national securities exchange or the
Nasdaq National Market and such other documents, reports and information
concerning the business and financial condition of the Company as the
Representatives may reasonably request, other than such documents, reports and
information for which the Company has the legal obligation not to reveal to the
Representatives.

                                       16


         (i) For a period of 90 days from the date hereof, the Company shall
not, directly or indirectly, offer for sale, sell or agree to sell or otherwise
dispose of any shares of Common Stock, or any securities convertible into,
exercisable or exchangeable for, or that are the economic or voting equivalent
of, any such shares of Common Stock, or announce the offering of, or register
with the Commission, any shares of Common Stock or any such other securities,
without your prior written consent; and the Company will use its best efforts to
cause the persons listed on Schedules II and III hereto not to, directly or
indirectly, offer for sale, sell or agree to sell or otherwise dispose of
(except for bona fide gifts) any shares of Common Stock, or any securities
convertible into, exercisable or exchangeable for, or that are the economic or
voting equivalent of, any shares of Common Stock for a period of 90 days from
the date hereof without your prior written consent; provided, however, that with
respect to the persons listed on Schedule III hereto, such period shall be 90
days from the date hereof.

         (j) The Company shall use its best efforts to obtain approval for
additional shares of Common Stock (such that all of the Shares shall be quoted
on or approved for quotation on the Nasdaq National Market), and maintain the
quotation of the Common Stock on the Nasdaq National Market, or in lieu thereof
a national securities exchange, and to remain so quoted for at least 5 years
from the Effective Date or for such shorter period as may be specified in a
written consent of the Representatives.

         (k) The Company will promptly provide you with copies of all
correspondence to and from, and all documents issued to and by, the Commission
in connection with the registration of the Shares under the 1933 Act or relating
to any documents incorporated by reference into the Registration Statement or
the Prospectus.

         (l) Subsequent to the date of this Agreement and through the date which
is the later of (i) the day following the date on which the Underwriters' option
to purchase the Option Shares shall expire or (ii) the day following the Option
Closing Date with respect to any Option Shares that the Underwriters shall elect
to purchase, except as described in or contemplated by the Prospectus, neither
the Company nor any of the Subsidiaries shall take any action (or refrain from
taking any action) which will result in the Company or the Subsidiaries
incurring any liability or obligation, direct or contingent, or enter into any
transaction, except in the ordinary course of business, and there will not be
any change in the financial position, capital stock, or any increase in
long-term debt, obligations under capital leases or short-term borrowings of the
Company and the Subsidiaries on a consolidated basis other than in the ordinary
course of business.

         (m) The Company shall not, for a period of 180 days after the date
hereof, without the prior written consent of the Representatives, redeem or call
for redemption, or prepay or give notice of prepayment (or announce any
redemption or call for redemption, or any repayment or notice of prepayment) of
any of the Company's securities which are convertible into Common Stock.

         (n) The Company shall not take, directly or indirectly, any action
designed to result in or which has constituted or which might cause or result in
stabilization or manipulation of the price of any security of the Company to
facilitate the sale or resale of the Shares and the Company is not aware of any
such action taken or to be taken by any affiliate of the Company.

         (o) Prior to the Closing Date (and, if applicable, the Option Closing
Date), the Company will not issue any press release or other communication
directly or indirectly or hold any press conference with respect to the Company,
the Subsidiaries or the offering of the Shares without your prior written
consent, which will not be unreasonably withheld.

         (p) The Company and the Subsidiaries shall conduct their businesses in
material compliance with all applicable federal and state laws, rules,
regulations, decisions, directives and orders (including, without limitation,
the applicable provisions of the 1933 Act, the 1933 Act Regulations, the 1934
Act, the 1934 Act Regulations, the BHC Act, the National Bank Act, the Federal
Deposit Insurance Corporation Improvement Act, the Oklahoma General Corporation
Act, the Oklahoma banking laws and all decisions, directives and orders of the
FDIC, the OCC, the Oklahoma Banking Commissioner, the Oklahoma Banking Board,
and the Board of Governors of the Federal Reserve System, as applicable).

                                       17


         (q) The Company and the Subsidiaries will maintain and keep accurate
books and records reflecting their assets and maintain internal accounting
controls which provide reasonable assurance that (i) transactions are executed
in accordance with management's authorization, (ii) transactions are recorded as
necessary to permit the preparation of the Company's consolidated financial
statements and to maintain accountability for the assets of the Company and its
Subsidiaries, (iii) access to the assets of the Company and its Subsidiaries is
permitted only in accordance with management's authorization, and (iv) the
recorded accounts of the assets of the Company and its Subsidiaries are compared
with existing assets at reasonable intervals.

         5. Payment of Expenses.

         (a) Whether or not this Agreement is terminated or the sale of the
Shares to the Underwriters is consummated, the Company covenants and agrees that
it will pay or cause to be paid (directly or by reimbursement) all costs and
expenses incident to the performance of the obligations of the Company under
this Agreement, including:

                  (i) the preparation, printing, filing, delivery and shipping
         of the initial registration statement, the Preliminary Prospectus or
         Prospectuses, the Registration Statement and the Prospectus and any
         amendments or supplements thereto, and the printing, delivery and
         shipping of this Agreement and any other underwriting documents
         (including, without limitation, underwriters' questionnaires,
         underwriters' powers of attorney, agreements among underwriters and
         selected dealers' agreements), the certificates for the Shares and the
         Preliminary and Final Blue Sky Memoranda and any legal investment
         surveys and any supplements thereto;

                  (ii) all fees, expenses and disbursements of the Company's
         counsel and accountants;

                  (iii) all fees and expenses incurred in connection with the
         qualification of the Shares under the securities or blue sky laws of
         such jurisdictions as you may request, including all filing fees and
         fees and disbursements of counsel for the Underwriters in connection
         therewith, including, without limitation, in connection with the
         preparation of the Preliminary and Final Blue Sky Memoranda and any
         legal investment surveys and any supplements thereto;

                  (iv) all fees and expenses incurred in connection with filings
         made with the NASD;

                  (v) any applicable fees and other expenses incurred in
         connection with the quotation of additional shares of Common Stock on
         the Nasdaq National Market;

                  (vi) the cost of furnishing to you as many copies as you
         reasonably request of the initial registration statements, any
         Preliminary Prospectus, the Registration Statement and the Prospectus
         and all amendments or supplements thereto;

                  (vii) the costs and charges of any transfer agent or registrar
         and the fees and disbursements of counsel for any transfer agent or
         registrar;

                                       18


                  (viii) all costs and expenses (including stock transfer taxes
         relating to the Shares to be sold by the Company) incurred in
         connection with the printing, issuance and delivery of the Shares to be
         sold by the Company to the Underwriters; and

                  (ix) all other costs and expenses incident to the performance
         of the obligations of the Company hereunder that are not otherwise
         specifically provided for in this Section 5.

         (b) If the sale of Shares contemplated by this Agreement is not
completed for any reason whatsoever, including, without limitation, if this
Agreement is terminated by the Company or by you for any reason whatsoever,
whether or not such termination is allowable hereunder, the Company will pay you
your accountable out-of-pocket expenses in connection herewith or in
contemplation of the performance of your obligations hereunder, including,
without limitation, travel expenses, reasonable fees, expenses and disbursements
of counsel or other out-of-pocket expenses incurred by you in connection with
any discussion of the offering of the Shares or the contents of the Registration
Statement, any investigation of the Company and the Subsidiaries, or any
preparation for the marketing, purchase, sale or delivery of the Shares in each
case following presentation of reasonably detailed invoices therefor.

         If the sale of the Shares contemplated by this Agreement is completed,
the Company shall not be responsible for payment of fees or disbursements of
counsel for the Underwriters other than in accordance with Section 5(a)(iii)
above, or for the reimbursement of any expenses of the Underwriters.

         6. Conditions of the Underwriters' Obligations. The obligations of the
Underwriters to purchase and pay for the Firm Shares and, following exercise of
the option granted by the Company in Section 1 of this Agreement, the Option
Shares, are subject, in your sole discretion, to the accuracy of and compliance
with the representations and warranties and agreements of the Company herein as
of the date hereof and as of the Closing Date (or in the case of the Option
Shares, if any, as of the Option Closing Date), to the accuracy of the written
statements of the Company and its officers made pursuant to the provisions
hereof, to the performance by the Company of its covenants and obligations
hereunder and to the following additional conditions:

         (a) If the Registration Statement or any amendment thereto filed prior
to the Closing Date has not been declared effective prior to the time of
execution hereof, the Registration Statement shall become effective not later
than 10:00 a.m., St. Louis time, on the first business day following the time of
execution of this Agreement, or at such later time and date as you may agree to
in writing. If required, the Prospectus and any amendment or supplement thereto
shall have been timely filed in accordance with Rule 424(b) and Rule 430A under
the 1933 Act and Section 4(a) hereof. No stop order suspending the effectiveness
of the Registration Statement or any amendment or supplement thereto shall have
been issued under the 1933 Act or any applicable state securities laws and no
proceedings for that purpose shall have been instituted or shall be pending, or,
to the knowledge of the Company or the Representatives, shall be contemplated by
the Commission or any state authority. Any request on the part of the Commission
or any state authority for additional information (to be included in the
Registration Statement or Prospectus or otherwise) shall have been disclosed to
you and complied with to your satisfaction and to the satisfaction of counsel
for the Underwriters.

         (b) No Underwriter shall have advised the Company at or before the
Closing Date (and, if applicable, the Option Closing Date) that the Registration
Statement or any post-effective amendment thereto, or the Prospectus or any
amendment or supplement thereto, contains an untrue statement of any fact which,
in your opinion, is material or omits to state a fact which, in your opinion, is
material and is required to be stated therein or is necessary to make statements
therein (in the case of the Prospectus or any amendment or supplement thereto,
in light of the circumstances under which they were made) not misleading.

                                       19


         (c) All corporate proceedings and other legal matters incident to the
authorization by the Company, form and validity of this Agreement, and the
authorization by the Company and form of the Registration Statement and
Prospectus, other than financial statements and other financial data, and all
other legal matters relating to this Agreement and the transactions contemplated
hereby shall be satisfactory in all respects to counsel for the Underwriters,
and the Company and the Subsidiaries shall have furnished to such counsel all
documents and information relating thereto that they may reasonably request to
enable them to pass upon such matters.

         (d) Kennedy & Baris, L.L.P., counsel for the Company, shall have
furnished to you their signed opinion, dated the Closing Date or the Option
Closing Date, as the case may be, in form and substance satisfactory to counsel
for the Underwriters, to the effect that:

                  (i) The Company has been duly incorporated and is validly
         existing and in good standing under the laws of the State of Oklahoma,
         and is duly registered as a financial holding company under the BHC
         Act. Each of the Company, Business Consulting Group, Inc. ("BCG"),
         Healthcare Strategic Support, Inc. ("HSS" and, together with the
         Company, the Banks, BCG and any other Significant Subsidiary of the
         Company, as that term is defined in Rule 1-02(w) of Regulation S-X, the
         "Opinion Parties") is duly incorporated or organized (as the case may
         be), validly existing and in good standing under the laws of its
         jurisdiction of incorporation or organization (as the case may be).
         Each of the Company and the Opinion Parties has full corporate power
         and authority to own or lease its properties and to conduct its
         business as such business is described in the Prospectus in all
         material respects and is currently conducted in all material respects.
         All outstanding shares of capital stock of the Opinion Parties have
         been duly authorized and validly issued and are fully paid and
         nonassessable (except to the extent such shares may be deemed
         assessable under 12 U.S.C. Section 55 or 12 U.S.C. Section 1831o) and,
         to such counsel's actual knowledge, except as disclosed in the
         Prospectus, there are no outstanding rights, options or warrants to
         purchase any such shares or securities convertible into or exchangeable
         for any such shares. Stillwater National Bank is a member of the
         Federal Reserve System, and to such counsel's knowledge, no proceedings
         for termination or revocation of such membership are pending or
         threatened. The deposit accounts of the Banks are insured by the FDIC
         up to the maximum amount provided by law, and, to such counsel's
         knowledge, no proceedings for the termination or revocation of any such
         insurance or such membership are pending or threatened.

                  (ii) The capital stock of the Company conforms to the
         description thereof contained in the Prospectus. The outstanding
         capital stock of the Company as of March 31, 2005 is as set forth under
         the caption "Capitalization" in the Prospectus, has been duly
         authorized and validly issued, is fully paid and nonassessable, and, to
         the knowledge of such counsel, not in violation of or subject to any
         other rights to subscribe for or purchase any securities. The form of
         certificates to evidence the Common Stock has been approved by the
         Board of Directors and is in due and proper form and complies with all
         applicable requirements. To such counsel's actual knowledge, there are
         no outstanding rights, options or warrants to purchase, no other
         outstanding securities convertible into or exchangeable for, and no
         commitments, plans or arrangements to issue, any shares of capital
         stock of the Company, except as described in the Prospectus, other than
         issuance to effect a possible stock split as set forth in the minutes
         of the Board of Directors of the Company.

                  (iii) The Company has all requisite corporate power and
         authority to issue, sell and deliver the Shares to be sold by the
         Company in accordance with and upon the terms and conditions set forth
         in this Agreement and in the Registration Statement and the Prospectus.
         All corporate action required to be taken by the Company for the
         authorization, issuance, sale and delivery of the Shares to be sold by
         the Company has been validly and sufficiently taken. All of the Shares
         to be sold by the Company have been duly and validly authorized and,
         when delivered in accordance with this Agreement, will be duly and
         validly issued, fully paid and nonassessable, and will conform to the
         description thereof in the Registration Statement and the Prospectus.
         Additional shares of Common Stock have been approved for quotation on
         the Nasdaq National Market subject to official notice of issuance, such
         that all of the Shares are quoted on, or have been approved for
         quotation (subject to official notice of issuance) on, the Nasdaq
         National Market. There are no preemptive or other rights to subscribe
         for or to purchase, and other than as disclosed in the Prospectus no
         restrictions upon the voting or transfer of, any shares of capital
         stock of the Company or the Opinion Parties pursuant to the corporate
         charter, by-laws or other governing documents of the Company or the
         Opinion Parties, or, to such counsel's actual knowledge, any agreement
         or other instrument to which the Company or any of the Opinion Parties
         is a party or by which the Company or any of the Opinion Parties may be
         bound.

                                       20


                  (iv) The Company has all requisite corporate power to enter
         into and perform its obligations under this Agreement and this
         Agreement has been duly and validly authorized, executed and delivered
         by the Company and constitutes the legal, valid and binding obligation
         of the Company enforceable in accordance with its terms, except as the
         enforcement hereof may be limited by general principles of equity and
         by bankruptcy or other laws relating to or affecting creditors' rights
         generally, and except as the indemnification and contribution
         provisions hereof may be limited under applicable laws and certain
         remedies may not be available in the case of a non-material breach.

                  (v) To such counsel's actual knowledge, neither the Company
         nor any other Opinion Party is in breach or violation of, or default
         under, with or without notice or lapse of time or both, its corporate
         charter, by-laws or other governing document. The execution, delivery
         and performance of this Agreement and the consummation of the
         transactions contemplated herein do not and will not conflict with,
         result in the creation or imposition of any material lien, claim,
         charge, encumbrance or restriction upon any property or assets of the
         Company or any Opinion Party or the Shares to be sold by the Company
         pursuant to, or constitute a material breach or violation of, or
         constitute a default under, with or without notice or lapse of time or
         both, any of the terms, provisions or conditions of the charter,
         by-laws or other governing document of the Company or any Opinion
         Party, or to such counsel's actual knowledge, any contract, indenture,
         mortgage, deed of trust, loan or credit agreement, note, lease,
         franchise, license or any other agreement or instrument to which the
         either the Company or any other Opinion Party is a party or by which
         any of them or any of their respective properties may be bound or any
         Permits or any other decree, judgment, rule or regulation, of any
         court, arbitrator, government, or governmental agency or
         instrumentality, domestic or foreign, known to such counsel having
         jurisdiction over the Company or an Opinion Party or any of their
         respective properties which, in each case, is material to the Company
         on a consolidated basis.

                  (vi) To the best of such counsel's actual knowledge, holders
         of securities of the Company either do not have any right that, if
         exercised, would require the Company to cause such securities to be
         included in the Registration Statement or have waived such right,
         except as adequately disclosed in the Prospectus. To the best of such
         counsel's actual knowledge, neither the Company nor any other Opinion
         Party is a party to any agreement or other instrument which grants
         rights for or relating to the registration of any securities of the
         Company except as adequately disclosed in the Prospectus.

                  (vii) Except as set forth in the Registration Statement and
         the Prospectus, to such counsel's actual knowledge, no action, suit or
         proceeding at law or in equity is pending or threatened in writing to
         which the Company or any other Opinion Party is or may be a party, and
         no action, suit or proceeding is pending or threatened in writing
         against or affecting the Company or any other Opinion Party or any of
         their properties before or by any court or governmental official,
         commission, board or other administrative agency, authority or body, or
         any arbitrator, wherein an unfavorable decision, ruling or finding
         could reasonably be expected to have a material adverse effect on the
         consummation of this Agreement or the issuance of the Shares to be sold
         by the Company or the sale of the Shares as contemplated herein or the
         condition (financial or otherwise), earnings, affairs, business,
         prospects or results of operations of the Company and the Subsidiaries
         on a consolidated basis or which is required to be disclosed in the
         Registration Statement or the Prospectus and is not so disclosed.

                                       21


                  (viii) No authorization, approval, consent or order of or
         filing, registration or qualification with, any person (including,
         without limitation, any court, governmental body or authority) is
         required to be made by the Company or any other Opinion Party in
         connection with the transactions contemplated by this Agreement, the
         Registration Statement and the Prospectus, except such as have been
         obtained under the 1933 Act, and such as may be required under state
         securities laws or Interpretations or Rules of the NASD in connection
         with the purchase and distribution of the Shares by the Underwriters,
         and from the Nasdaq National Market relating to the approval for
         quotation of the additional shares of Common Stock. The issuance of the
         Shares and the share repurchase described in the Prospectus have been
         conducted in compliance with applicable federal securities laws, rules
         and regulations.

                  (ix) The Registration Statement and the Prospectus and any
         amendments or supplements thereto and any documents incorporated
         therein by reference (other than the financial statements or other
         financial data included therein or omitted therefrom and Underwriters'
         Information as to which such counsel need express no opinion) comply as
         to form in all material respects with the requirements of the 1933 Act
         and the 1933 Act Regulations as of their respective dates of
         effectiveness; the conditions for use of Form S-3 have been satisfied;
         and, except as amended or superseded by a subsequently filed document,
         as of the date they were filed with the Commission, the documents
         incorporated by reference in the Prospectus appear on their face to
         comply as to form and be appropriately responsive in all material
         respects with the requirements of the 1934 Act and the applicable 1934
         Act Regulations (other than the financial statements or other financial
         data included therein or omitted therefrom).

                  (x) To such counsel's actual knowledge, there are no
         contracts, agreements, leases or other documents of a character
         required to be disclosed in the Registration Statement or Prospectus or
         to be filed as exhibits to the Registration Statement that are not so
         disclosed or filed.

                  (xi) The statements under the captions "Risk Factors" and
         "Capitalization" in the Prospectus and in Item 15 of Part II of the
         Registration Statement and in the Company's Annual Report on Form 10-K
         for the year ended December 31, 2004 under Item 1, "Business --
         General" and "Regulation, Supervision, and Governmental Policy", Item
         11, "Executive Compensation" and Item 13, "Certain Relationships and
         Related Transactions" and the description of common stock incorporated
         by reference in the Prospectus, insofar as such statements constitute a
         summary of legal and regulatory matters, documents or proceedings
         referred to therein are accurate descriptions of the matters summarized
         therein in all material respects and fairly present the information
         called for with respect to such legal and regulatory matters, documents
         and proceedings in all material respects, other than financial and
         statistical data as to which said counsel expresses no opinion or
         belief.

                  (xii) Such counsel has been advised by the staff of the
         Commission that the Registration Statement has become effective under
         the 1933 Act; any required filing of the Prospectus pursuant to Rule
         424(b) has been made within the time period required by Rule 424(b); to
         the best of such counsel's knowledge, no stop order suspending the
         effectiveness of the Registration Statement has been issued and no
         proceedings for a stop order are pending or threatened by the
         Commission.

                  (xiii) Except as described in or contemplated by the
         Prospectus, to the best of such counsel's knowledge, there are no
         contractual encumbrances or restrictions, or no material legal
         restrictions (excluding any encumbrances or restrictions of general
         application to national banks contained in laws, rules and regulations
         of applicable regulatory authorities) required to be described therein,
         on the ability of the Opinion Parties (A) to pay dividends or make any
         other distributions on its capital stock or to pay indebtedness owed to
         the Company, (B) to make any loans or advances to, or investments in,
         the Company or (C) to transfer any of its property or assets to the
         Company.

                                       22


                  (xiv) To such counsel's actual knowledge, (A) the business and
         operations of the Company and the Opinion Parties comply in all
         material respects with all statutes, ordinances, laws, rules and
         regulations applicable thereto, except in those instances where
         non-compliance would not materially impair the ability of the Company
         and the Subsidiaries to conduct their businesses; and (B) the Company
         and the Opinion Parties possess and are operating in all material
         respects in compliance with the terms, provisions and conditions of all
         Permits known to such counsel and required to conduct their businesses
         as described in the Prospectus and which are material to the Company
         and the Subsidiaries on a consolidated basis, except in those instances
         where the loss thereof or non-compliance therewith would not have an
         adverse effect on the condition (financial or otherwise), earnings,
         affairs, business, prospects or results of operations of the Company
         and the Subsidiaries on a consolidated basis; such counsel has no
         actual knowledge that any such Permit is not valid and in full force
         and effect, and such counsel has no actual knowledge of any action,
         suit or proceeding that is pending or threatened (or any basis
         therefor) which may lead to the revocation, termination, suspension or
         non-renewal of any such Permit, except in those instances where the
         loss thereof or non-compliance therewith would not materially impair
         the ability of the Company or the Opinion Parties to conduct their
         businesses.

         In giving this opinion, such counsel may rely, as to matters governed
by the laws of Oklahoma and as to the ownership of the capital stock of the Bank
by the Company, and the due authorization and valid issuance of fully paid and
nonassessable stock of the Company and its Subsidiaries, upon the opinion of
Hert Baker & Koemel, P.C. rendered pursuant to Section 6(e) hereof. Such counsel
may also state that, insofar as such opinion involves factual matters, they have
relied upon certificates of officers of the Company including, without
limitation, certificates as to the identity of any and all material contracts,
indentures, mortgages, deeds of trust, loans or credit agreements, notes,
leases, franchises, licenses or other agreements or instruments, and all
material permits, easements, consents, licenses, franchises and government
regulatory authorizations, for purposes of paragraphs (v), (x) and (xiv) hereof
and certificates of public officials.

         Such counsel shall also confirm that, in connection with the
preparation of the Registration Statement and Prospectus, such counsel has
participated in conferences with officers and representatives of the Company and
with its independent public accountants and with the Representatives and their
counsel, at which conferences such counsel made inquiries of such officers,
representatives and accountants and discussed in detail the contents of the
Registration Statement and Prospectus and the documents incorporated therein by
reference and such counsel has no reason to believe (A) that the Registration
Statement or any amendment thereto (except for the financial statements and
related schedules and statistical data included therein or omitted therefrom,
and the Underwriters' Information, as to which such counsel need express no
opinion), at the time the Registration Statement or any such amendment became
effective, contained any untrue statement of material fact or omitted to state
any material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading or (B) that the Prospectus or any amendment or supplement thereto
or the documents incorporated therein by reference (except for the financial
statements and related schedules and statistical data included therein or
omitted therefrom, and the Underwriters' Information, as to which such counsel
need express no opinion), at the time the Registration Statement became
effective (or, if the term "Prospectus" refers to the prospectus first filed
pursuant to Rule 424(b) of the 1933 Act Regulations, at the time the Prospectus
was issued), at the time any such amended or supplemented Prospectus was issued,
at the Closing Date and, if applicable, the Option Closing Date, contained or
contains any untrue statement of material fact or omitted or omits to state any
material fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading or (C) that there is any amendment to the Registration Statement
required to be filed that has not already been filed.

                                       23


         (e) James I. Lundy, III, counsel for the Company, shall have furnished
to you his signed opinion, dated the Closing Date or the Option Closing Date, as
the case may be, in form and substance satisfactory to counsel for the
Underwriters, to the effect that the issuance of the Shares and the share
repurchase described in the Prospectus have been conducted in compliance with
applicable federal securities laws, rules and regulations. Such counsel shall
also confirm that, in connection with the preparation of the Registration
Statement and Prospectus, such counsel has participated in conferences with
officers and representatives of the Company and with its independent public
accountants and with the Representatives and their counsel, at which conferences
such counsel made inquiries of such officers, representatives and accountants
and discussed in detail the contents of the Registration Statement and
Prospectus and the documents incorporated therein by reference and such counsel
has no reason to believe (A) that the Registration Statement or any amendment
thereto (except for the financial statements and related schedules and
statistical data included therein or omitted therefrom, and the Underwriters'
Information, as to which such counsel need express no opinion), at the time the
Registration Statement or any such amendment became effective, contained any
untrue statement of material fact or omitted to state any material fact required
to be stated therein or necessary to make the statements therein, in light of
the circumstances under which they were made, not misleading or (B) that the
Prospectus or any amendment or supplement thereto or the documents incorporated
therein by reference (except for the financial statements and related schedules
and statistical data included therein or omitted therefrom, and the
Underwriters' Information, as to which such counsel need express no opinion), at
the time the Registration Statement became effective (or, if the term
"Prospectus" refers to the prospectus first filed pursuant to Rule 424(b) of the
1933 Act Regulations, at the time the Prospectus was issued), at the time any
such amended or supplemented Prospectus was issued, at the Closing Date and, if
applicable, the Option Closing Date, contained or contains any untrue statement
of material fact or omitted or omits to state any material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading or (C) that there is
any amendment to the Registration Statement required to be filed that has not
already been filed.

         (f) Hert Baker & Koemel, P.C., counsel for the Company, shall have
furnished to you their signed opinion, dated the Closing Date or the Option
Closing Date, as the case may be, in form and substance satisfactory to counsel
for the Underwriters, to the effect that:

                  (i) Each of the Opinion Parties, Cash Source, Inc. ("CSI"),
         CRK Properties, Inc. ("CRK"), SWB, Inc. ("SWB"), SNB Insurance Agency,
         Inc. ("SNB Insurance"), Stillwater National Building Corporation
         ("SNBC"), BNS, Inc. ("BNS"), Stillwater Properties, Inc. ("SPI") and
         Grand Hill Investments, LLC ("GHI") has been duly incorporated and is
         validly existing and in good standing under the laws of the State of
         Oklahoma. The Company is duly registered as a financial holding company
         under the BHC Act. Stillwater National Bank is a national banking
         association duly incorporated, validly existing and in good standing
         under the laws of the United States of America. Stillwater National
         Bank is a member of the Federal Reserve System, and to the knowledge of
         such counsel, no proceedings for the termination or revocation of such
         membership are pending or threatened. The deposit accounts of the Banks
         are insured by the FDIC up to the maximum amount provided by law, and
         to the knowledge of such counsel, no proceedings for the termination or
         revocation of any such insurance or such membership are pending or
         threatened. Each of the Opinion Parties has full corporate power and
         authority to conduct its business as described in the Prospectus in all
         material respects and as currently conducted in all material respects.
         Except as disclosed in the Prospectus, to the best of such counsel's
         knowledge, the Company owns directly, free and clear of any security
         interests, mortgage, pledge, lien, charge, encumbrance, restriction
         upon voting or transfer, preemptive rights or any other claim or
         equity, (A) all outstanding shares of capital stock of the Subsidiaries
         other than SBI Capital Trust I, OKSB Statutory Trust I, and SBI Capital
         Trust II and (B) all of the outstanding common securities of SBI
         Capital Trust I, OKSB Statutory Trust I and SBI Capital Trust II. All
         of such shares of capital stock of the Subsidiaries have been duly
         authorized and validly issued and are fully paid and nonassessable
         (except to the extent such shares may be deemed assessable under 12
         U.S.C. Section 55 or 12 U.S.C. Section 1831o) and, to the best of such
         counsel's knowledge, except as disclosed in the Prospectus, there are
         no outstanding rights, options or warrants to purchase any such shares
         or common securities or securities convertible into or exchangeable for
         any such shares or common securities.

                                       24


                  (ii) The capital stock of the Company conforms to the
         description thereof contained in the Prospectus in all material
         respects. The outstanding capital stock of the Company as of March 31,
         2005 is as set forth under the caption "Capitalization" in the
         Prospectus, has been duly authorized and validly issued, is fully paid
         and nonassessable and, to the knowledge of such counsel, has been
         issued in compliance with applicable federal and state securities laws
         not in violation of or subject to any other rights to subscribe for or
         purchase any securities. The form of certificates to evidence the
         Common Stock is in due and proper form and complies with all applicable
         requirements of Oklahoma law. To the best of such counsel's knowledge,
         there are no outstanding rights, options or warrants to purchase, no
         other outstanding securities convertible into or exchangeable for, and
         no commitments, plans or arrangements to issue, any shares of capital
         stock of the Company, except as described in the Prospectus.

                  (iii) There are no preemptive or other rights to subscribe for
         or to purchase, and, other than as described in the Prospectus, no
         restrictions upon the voting or transfer of, any shares of capital
         stock of the Opinion Parties pursuant to the corporate charter, by-laws
         or other governing documents of the Opinion Parties or, to the best of
         such counsel's knowledge, pursuant to any agreement or other instrument
         to which any of the Opinion Parties is a party or by which any of the
         Opinion Parties may be bound.

                  (iv) The Company has all requisite corporate power to enter
         into and perform its obligations under this Agreement and this
         Agreement has been duly and validly authorized, executed and delivered
         by the Company and constitutes the legal, valid and binding obligation
         of the Company enforceable in accordance with its terms, except as the
         enforcement hereof may be limited by general principles of equity and
         by bankruptcy or other laws relating to or affecting creditors' rights
         generally, and except as the indemnification and contribution
         provisions hereof may be limited under applicable laws and certain
         remedies may not be available in the case of a non-material breach.

                  (v) To the best of such counsel's knowledge, neither the
         Company, nor any other Opinion Party is in breach or violation of, or
         default under, with or without notice or lapse of time or both, its
         corporate charter, by-laws or other governing document. The execution,
         delivery and performance of this Agreement and the consummation of the
         transactions contemplated herein do not and will not conflict with,
         result in the creation or imposition of any material lien, claim,
         charge, encumbrance or restriction upon any property or assets of any
         Opinion Party or the Shares to be sold by the Company pursuant to, or
         constitute a material breach or violation of, or constitute a material
         default under, with or without notice or lapse of time or both, any of
         the terms, provisions or conditions of the charter, by-laws or other
         governing document of any Opinion Party, or to the best knowledge of
         such counsel's after due inquiry, any material contract, indenture,
         mortgage, deed of trust, loan or credit agreement, note, lease,
         franchise, license or any other agreement or instrument to which any
         Opinion Party is a party or by which any of them or any of their
         respective properties may be bound or any Permits or any other decree,
         judgment, rule or regulation, of any court, arbitrator, government, or
         governmental agency or instrumentality, domestic or foreign, having
         jurisdiction over an Opinion Party or any of their respective
         properties which, in each case, is material to the Company on a
         consolidated basis. No authorization, approval, consent or order of, or
         filing, registration or qualification with, any person (including,
         without limitation, any court, governmental body or authority) is
         required under Oklahoma law in connection with the transactions
         contemplated by this Agreement except as may be required under Oklahoma
         securities laws in connection with the purchase and distribution of the
         Shares by the Underwriters.

                                       25


                  (vi) To the best of such counsel's knowledge, holders of
         securities of the Company either do not have any right that, if
         exercised, would require the Company to cause such securities to be
         included in the Registration Statement or have waived such right,
         except as adequately disclosed in the Prospectus. To the best of such
         counsel's knowledge, neither the Company nor any other Opinion Party is
         a party to any agreement or other instrument which grants rights for or
         relating to the registration of any securities of the Company except as
         described in the Prospectus.

                  (vii) Except as set forth in the Registration Statement and
         the Prospectus, to the best of such counsel's knowledge, no action,
         suit or proceeding at law or in equity is pending or threatened in
         writing to which the Company or any of the Subsidiaries is or may be a
         party, and no action, suit or proceeding is pending or threatened in
         writing against or affecting the Company or any of the Subsidiaries or
         any of their properties before or by any court or governmental
         official, commission, board or other administrative agency, authority
         or body, or any arbitrator, wherein an unfavorable decision, ruling or
         finding could reasonably be expected to have a material adverse effect
         on the consummation of this Agreement or the transactions contemplated
         herein or the condition (financial or otherwise), earnings, affairs,
         business, prospects or results of operations of the Company and the
         Subsidiaries on a consolidated basis.

                  (viii) No authorization, approval, consent or order of or
         filing, registration or qualification with, any person (including,
         without limitation, any court, governmental body or authority) is
         required under Oklahoma law in connection with the transactions
         contemplated by this Agreement except such as may be required under
         Oklahoma securities laws in connection with the purchase and
         distribution of the Shares by the Underwriters.

                  (ix) To such counsel's knowledge, based solely upon
         identification of material contracts, agreements, leases and other
         material documents by the Company, there is no material contract,
         agreement, lease, or other document which has not been made in the
         ordinary course of business and either is to be performed in whole or
         in part at or after January 26, 2005 or within the preceding
         twenty-four months and (A) to which any director, officer, or
         security-holder named in the Registration Statement is a party (other
         than any contract involving only the purchase or sale of current assets
         having a determinable market price, at such market price); (B) call for
         the acquisition or sale of any property or equipment for a
         consideration exceeding fifteen percent (15%) of consolidated fixed
         assets of the Company at December 31, 2004; (C) is a material lease
         under which any of the Opinion Parties holds property described in the
         Registration Statement; or (D) is a management contract or compensatory
         plan, contract or arrangement in which any director or any officer of
         the Company named in the Registration Statement participates, and which
         has not been described in or filed as an exhibit to the Registration
         Statement.

                  (x) The statements under the captions "Risk Factors" and
         "Capitalization" in the Prospectus and in Item 15 of Part II of the
         Registration Statement and in the Company's Annual Report on Form 10-K
         for the year ended December 31, 2004 under Item 1, "Business --
         General" and "Regulation, Supervision and Governmental Policy", Item
         11, "Executive Compensation" and Item 13, "Certain Relationships and
         Related Transactions," and the description of common stock incorporated
         by reference in the Prospectus, insofar as such statements constitute a
         summary of legal and regulatory matters, documents or proceedings
         referred to therein and depend upon, refer to, or describe Oklahoma
         law, are, to the best of such counsel's knowledge, accurate in all
         material respects and fairly present the information called for with
         respect to such legal and regulatory matters, documents and
         proceedings.

                                       26


                  (xi) Except as set forth in the Prospectus, to the best of
         such counsel's knowledge, there are no contractual encumbrances or
         restrictions, or material legal restrictions, on the ability of the
         Subsidiaries (A) to pay dividends or make any other distributions on
         its capital stock or to pay indebtedness owed to the Company, (B) to
         make any loans or advances to, or investments in, the Company or (C) to
         transfer any of its property or assets to the Company.

                  (xii) To the best of such counsel's knowledge, (A) the
         business and operations of the Company and the Subsidiaries comply in
         all material respects with all statutes, ordinances, laws, rules and
         regulations applicable thereto and which are material to the Company
         and the Subsidiaries on a consolidated basis, except in those instances
         where non-compliance would not materially impair the ability of the
         Company or any of its Subsidiaries to conduct their businesses; and (B)
         the Company and the Subsidiaries possess and are operating in all
         material respects in compliance with the terms, provisions and
         conditions of all Permits known to such counsel and required to conduct
         their businesses as described in the Prospectus and which are material
         to the Company and the Subsidiaries on a consolidated basis, except in
         those instances where the loss thereof or non-compliance therewith
         would not have a material adverse effect on the condition (financial or
         otherwise), earnings, affairs, business, prospects or results of
         operations of the Company and the Subsidiaries on a consolidated basis,
         such counsel has no knowledge that any such Permit is not valid and in
         full force and effect, and such counsel has no knowledge of any action,
         suit or proceeding that is pending or threatened (or any basis
         therefor) which may lead to the revocation, termination, suspension of
         any such Permit, except in those instances where the loss thereof or
         non-compliance therewith would not materially impair the ability of the
         Company or any of its Subsidiaries to conduct their businesses.

         In giving this opinion such counsel may state that, insofar as such
opinion involves factual matters, they have relied, to the extent they deem
proper, upon certificates of officers of the Company, including, without
limitation, certificates as to the identity of any and all material contracts,
indentures, mortgages, deeds of trust, loans or credit agreements, notes,
leases, franchises, licenses or other agreements or instruments, and all
material permits, consents, licenses, franchises and government regulatory
authorizations, for purposes of paragraphs (v), (ix) and (xii) hereof and
certificates of public officials.

         Such counsel shall state that Kennedy & Baris, L.L.P. and Bryan Cave
LLP may rely on their opinion in rendering the opinions required by Sections
6(d) and 6(g).

         (g) Bryan Cave LLP, counsel for the Underwriters, shall have furnished
you their signed opinion, dated the Closing Date or the Option Closing Date, as
the case may be, with respect to the sufficiency of all corporate procedures and
other legal matters relating to this Agreement, the validity of the Shares, the
Registration Statement, the Prospectus and such other related matters as you may
reasonably request and there shall have been furnished to such counsel such
documents and other information as they may request to enable them to pass on
such matters. In giving such opinion, Bryan Cave LLP may rely as to matters of
fact upon statements and certifications of officers of the Company and of other
appropriate persons and may rely as to matters of law, other than law of the
United States and the State of Missouri, and upon the opinions of James I.
Lundy, III, Kennedy & Baris, L.L.P. and Hert Baker & Koemel, P.C. described
herein.

         (h) On the date of this Agreement and on the Closing Date (and, if
applicable, any Option Closing Date), the Representatives on behalf of the
Underwriters shall have received from Ernst & Young LLP a letter, dated the date
of this Agreement and the Closing Date (and, if applicable, the Option Closing
Date), respectively, in form and substance satisfactory to the Representatives,
confirming that they are independent public accountants with respect to the
Company and the Subsidiaries, within the meaning of the 1933 Act and the 1933
Act Regulations, and stating in effect that:

                                       27


                  (i) In their opinion, the consolidated financial statements,
         including the notes thereto, of the Company and its Subsidiaries
         audited by them and included or incorporated by reference in the
         Registration Statement comply as to form in all material respects with
         the applicable accounting requirements of the 1933 Act and the 1933 Act
         Regulations.

                  (ii) On the basis of the procedures specified by the Public
         Company Accounting Oversight Board (United States) for a review of
         interim financial information as described in AU722, "Interim Financial
         Information", inquiries of officials of the Company and its
         Subsidiaries responsible for financial and accounting matters, and such
         other inquiries and procedures as may be specified in such letter,
         which procedures do not constitute an audit in accordance with U.S.
         generally accepted auditing standards, nothing came to their attention
         that caused them to believe that, if applicable, the unaudited interim
         consolidated financial statements of the Company and its Subsidiaries
         included in the Registration Statement do not comply as to form in all
         material respects with the applicable accounting requirements of the
         1934 Act and 1934 Act Regulations or are not in conformity with U.S.
         generally accepted accounting principles applied on a basis
         substantially consistent, except as noted in the Registration Statement
         with the basis for the audited consolidated financial statements of the
         Company and its Subsidiaries included in the Registration Statement.

                  (iii) On the basis of limited procedures, not constituting an
         audit in accordance with U.S. generally accepted auditing standards,
         consisting of a reading of the unaudited interim financial statements
         of the Company and its Subsidiaries and other information referred to
         below, a reading of the latest available unaudited financial statements
         of the Company and its Subsidiaries, inspection of the minute books of
         the Company and its Subsidiaries since the date of the latest audited
         financial statements of the Company and its Subsidiaries included or
         incorporated by reference in the Registration Statement, inquiries of
         officials of the Company and its Subsidiaries responsible for financial
         and accounting matters and such other inquiries and procedures as may
         be specified in such letter, nothing came to their attention that
         caused them to believe that:

                           (A) as of a specified date not more than five days
                  prior to the date of such letter, there have been any changes
                  in the capital stock, allowance for loan losses, or net loans
                  receivable of the Company and its Subsidiaries other than
                  changes related to the Employee Stock Purchase Plan and/or
                  Dividend Reinvestment Plan, any increase in the long-term
                  debt, short-term borrowings, obligations under capital leases
                  or real estate owned of the Company or its Subsidiaries, any
                  decreases in consolidated total assets or shareholders' equity
                  of the Company or its Subsidiaries, or any changes, decreases
                  or increases in other items specified by the Underwriters, in
                  each case as compared with amounts shown in the latest
                  unaudited interim consolidated statement of financial
                  condition of the Company or its Subsidiaries included or
                  incorporated by reference in the Registration Statement except
                  in each case for changes, increases or decreases which the
                  Registration Statement specifically discloses have occurred or
                  may occur or which are described in such letter; and

                           (B) for the period from the date of the latest
                  unaudited interim consolidated financial statements included
                  or incorporated by reference in the Registration Statement to
                  the specified date referred to in Clause (iii)(A), there were
                  any decreases in the interest income, net interest income,
                  other income or net income of the Company and its Subsidiaries
                  or in the basic and diluted earnings per common share of the
                  Company and its Subsidiaries, any increase in other expense of
                  the Company and its Subsidiaries, or any changes, decreases or
                  increases in any other items specified by the Representatives,
                  in each case as compared with the comparable period of the
                  preceding year and with any other period of corresponding
                  length specified by the Underwriters, except in each case for
                  changes, increases or decreases which the Registration
                  Statement discloses have occurred or may occur, or which are
                  described in such letter.

                                       28


                  (iv) In addition to the audit referred to in their report
         included in the Registration Statement and the limited procedures,
         inspection of minute books, inquiries and other procedures referred to
         in paragraphs (ii) and (iii) above, they have carried out certain
         specified procedures, not constituting an audit in accordance with U.S.
         generally accepted auditing standards, with respect to certain amounts,
         percentages and financial information specified by the Representatives
         which are derived from the general accounting records and consolidated
         financial statements of the Company and its Subsidiaries which appear
         or are incorporated by reference in the Registration Statement, and
         have compared such amounts, percentages and financial information with
         the accounting records and the material derived from such records and
         consolidated financial statements of the Company and its Subsidiaries
         and have found them to be in agreement.

         In the event that the letters to be delivered referred to above set
forth any such changes, decreases or increases as specified in Clauses (iii)(A)
or (iii)(B) above, or any exceptions from such agreement specified in Clause
(iv) above, it shall be a further condition to the obligations of the
Underwriters that the Representatives shall have determined, after discussions
with officers of the Company and its Subsidiaries responsible for financial and
accounting matters, that such changes, decreases, increases or exceptions as are
set forth in such letters do not (x) reflect an adverse change in the items
specified in Clause (iii)(A) above as compared with the amounts shown in the
latest unaudited consolidated statement of financial condition of the Company
and its Subsidiaries included in the Registration Statement, (y) reflect an
adverse change in the items specified in Clause (iii)(B) above as compared with
the corresponding periods of the prior year or other period specified by the
Representatives, or (z) reflect a material change in items specified in Clause
(iv) above from the amounts shown in the Preliminary Prospectus distributed by
the Underwriters in connection with the offering contemplated hereby or from the
amounts shown in the Prospectus.

         (i) At the Closing Date and, if applicable, the Option Closing Date,
you shall have received certificates of each of the chief executive officer and
the chief financial and accounting officer of the Company, which certificates
shall be deemed to be made on behalf of the Company, dated as of the Closing
Date and, if applicable, the Option Closing Date, evidencing satisfaction of the
conditions of Section 6(a) and stating that (A) the representations and
warranties of the Company set forth in Section 2 hereof are accurate as of the
Closing Date and, if applicable, the Option Closing Date, and that the Company
has complied with all agreements and satisfied all conditions on its part to be
performed or satisfied at or prior to such Closing Date; (B) since the
respective dates as of which information is given in the Registration Statement
and the Prospectus, there has not been any material adverse change in the
condition (financial or otherwise), earnings, affairs, business, prospects or
results of operations of the Company and the Subsidiaries on a consolidated
basis; (C) since such dates there has not been any material transaction entered
into by the Company or the Subsidiaries other than transactions in the ordinary
course of business; (D) each such officer has carefully examined the
Registration Statement and the Prospectus as amended or supplemented and all
documents incorporated therein by reference and nothing has come to its or his
attention that would lead it or him to believe that either the Registration
Statement or the Prospectus, or any amendment or supplement thereto or any
document incorporated therein by reference as of their respective effective or
issue dates, contained, and the Prospectus as amended or supplemented and any
document incorporated therein by reference at such Closing Date (and, if
applicable, the Option Closing Date), contains any untrue statement of fact, or
omits to state any fact required to be stated therein or necessary in order to
make the statements therein, in the light of the circumstances under which they
were made, not misleading; and (E) covering such other matters as you may
request. The officers' certificate of the Company shall further state that no
stop order affecting the Registration Statement is in effect or, to their
knowledge, threatened.

         (j) The NASD, upon review of the terms of the public offering of the
Shares, shall not have objected to any Underwriter's participation in such
offering.

                                       29


         (k) Prior to the Closing Date and, if applicable, the Option Closing
Date, the Company shall have furnished to you and counsel for the Underwriters
all such other documents, certificates and opinions as they have reasonably
requested.

         (l) Prior to the date hereof, each person identified on Schedule II and
III hereto shall have executed and delivered to the Underwriters an agreement,
in form satisfactory to the Underwriters, providing that such person shall not,
for a period of 90 days or 180 days, as the case may be, from the date hereof,
directly or indirectly, offer for sale, sell or agree to sell or otherwise
dispose of (except for bona fide gifts) any shares of Common Stock, or any
securities convertible into, exercisable or exchangeable for, or that are the
economic or voting equivalent of, any such shares of Common Stock without your
prior written consent.

         All opinions, certificates, letters and other documents shall be in
compliance with the provisions hereof only if they are reasonably satisfactory
in form and substance to you and your counsel. Any certificate signed by an
officer of the Company and delivered to you pursuant hereto shall also be deemed
to be a representation and warranty of the Company to the Underwriters as to the
statements made therein. The Company shall furnish you with conformed copies of
such opinions, certificates, letters and other documents as you shall reasonably
request.

         If any of the conditions referred to in this Section 6 shall not have
been fulfilled when and as required by this Agreement, this Agreement and all
obligations of the Underwriters hereunder may be terminated by you on notice to
the Company at, or at any time before, the Closing Date or the Option Closing
Date, as applicable. Any such termination shall be without liability of the
Underwriters to the Company.

         7. Indemnification and Contribution.

         (a) The Company agrees to indemnify and hold harmless each Underwriter,
each of its directors, officers and agents, and each person, if any, who
controls any Underwriter within the meaning of the 1933 Act, against any and all
losses, claims, damages, liabilities and expenses (including reasonable costs of
investigation and reasonable attorneys' fees and expenses), joint or several,
arising out of or based (i) upon any untrue statement or alleged untrue
statement of fact made by the Company contained in Section 2(a) of this
Agreement (or any certificate delivered by the Company pursuant hereto) or the
registration statement as originally filed or the Registration Statement, any
Preliminary Prospectus or the Prospectus, or in any amendment or supplement
thereto, (ii) upon any blue sky application or other document executed by the
Company specifically for that purpose or based upon written information
furnished by the Company filed in any state or other jurisdiction in order to
qualify any of the Shares under the securities laws thereof (any such
application, document or information being hereinafter referred to as a "Blue
Sky Application"), (iii) any omission or alleged omission to state a fact in the
registration statement as originally filed or the Registration Statement, any
Preliminary Prospectus or the Prospectus, or in any amendment or supplement
thereto, or in any Blue Sky Application required to be stated therein or
necessary to make the statements therein not misleading, and against any and all
losses, claims, damages, liabilities and expenses (including reasonable costs of
investigation and attorneys' fees and expenses), joint or several, arising out
of or based upon any untrue statement or alleged untrue statement of fact
contained in any Preliminary Prospectus or the Prospectus, or in any amendment
or supplement thereto, or arising out of or based upon any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading or (iv) the enforcement of this
indemnification provision or the contribution provisions of Section 7(e); and
shall reimburse each such indemnified party for any reasonable legal or other
expenses as incurred, but in no event less frequently than 30 days after each
invoice is submitted, incurred by them in connection with investigating or
defending against or appearing as a third-party witness in connection with any
such loss, claim, damage, liability or action, notwithstanding the possibility
that payments for such expenses might later be held to be improper, in which
case such payments shall be promptly refunded; provided, however, that the
Company shall not be liable in any such case to the extent, but only to the
extent, that any such losses, claims, damages, liabilities and expenses arise
out of or are based upon any untrue statement or omission or allegation thereof
that has been made therein or omitted therefrom in reliance upon and in
conformity with information furnished in writing to the Company through you by
or on behalf of any Underwriter expressly for use therein beneath the heading
"Underwriting;" provided, that the indemnification contained in this paragraph
with respect to any Preliminary Prospectus shall not inure to the benefit of any
Underwriter (or of any of its directors, officers or agents or any person
controlling such Underwriter) to the extent any such losses, claims, damages,
liabilities or expenses directly results from the fact that such Underwriter
sold Shares to a person to whom there was not sent or given, at or prior to the
written confirmation of such sale, a copy of the Prospectus (as amended or
supplemented if any amendments or supplements thereto shall have been furnished
to such Underwriter in sufficient time to distribute same with or prior to the
written confirmation of the sale involved), if required by law, and if such
loss, claim, damage, liability or expense would not have arisen but for the
failure to give or send such person such document. The foregoing indemnity
agreement is in addition to any liability the Company may otherwise have to any
such indemnified party.

                                       30


         (b) Each Underwriter, severally and not jointly, agrees to indemnify
and hold harmless the Company, each of its directors, each of its officers who
signed the Registration Statement (and each person, if any, who controls the
Company within the meaning of the 1933 Act), to the same extent as required by
the foregoing indemnity from the Company to each Underwriter, but only with
respect to information relating to such Underwriter furnished in writing to the
Company through you by or on behalf of it expressly for use in connection with
the registration statement as originally filed, the Registration Statement, any
Preliminary Prospectus, the Prospectus or any amendment or supplement thereto,
beneath the heading "Underwriting" or in a Blue Sky Application. The foregoing
indemnity agreement is in addition to any liability which any Underwriter may
otherwise have to any such indemnified party.

         (c) If any action or claim shall be brought or asserted against any
indemnified party or any person controlling an indemnified party in respect of
which indemnity may be sought from the indemnifying party, such indemnified
party or controlling person shall promptly notify the indemnifying party in
writing, and the indemnifying party shall assume the defense thereof, including
the employment of counsel reasonably satisfactory to the indemnified party and
the payment of all expenses; provided, however, that the failure so to notify
the indemnifying party shall not relieve it from any liability which it may have
to an indemnified party otherwise than under such paragraph, and further, shall
only relieve it from liability under such paragraph to the extent prejudiced
thereby. Any indemnified party or any such controlling person shall have the
right to employ separate counsel in any such action and to participate in the
defense thereof, but the fees and expenses of such counsel shall be at the
expense of such indemnified party or such controlling person unless (i) the
employment thereof has been specifically authorized by the indemnifying party in
writing, (ii) the indemnifying party has failed to assume the defense or to
employ counsel reasonably satisfactory to the indemnified party or (iii) the
named parties to any such action (including any impleaded parties) include both
such indemnified party or such controlling person and the indemnifying party and
such indemnified party or such controlling person shall have been advised by
such counsel that there may be one or more legal defenses available to it that
are different from or in addition to those available to the indemnifying party
(in which case, if such indemnified party or controlling person notifies the
indemnifying party in writing that it elects to employ separate counsel at the
expense of the indemnifying party, the indemnifying party shall not have the
right to assume the defense of such action on behalf of such indemnified party
or such controlling person); it being understood, however, that the indemnifying
party shall not, in connection with any one such action or separate but
substantially similar or related actions in the same jurisdiction arising out of
the same general allegations or circumstances, be liable for the reasonable fees
and expenses of more than one separate firm of attorneys at any time and for
such indemnified party and controlling persons, such firm shall be designated in
writing by the indemnified party. Each indemnified party and each controlling
person, as a condition of such indemnity, shall use reasonable efforts to
cooperate with the indemnifying party in the defense of any such action or
claim. The indemnifying party shall not be liable for any settlement of any such
action effected without its written consent, but if there be a final judgment
for the plaintiff in any such action, the indemnifying party agrees to indemnify
and hold harmless any indemnified party and any such controlling person from and
against any loss, claim, damage, liability or expense by reason of such
settlement or judgment.

                                       31


         An indemnifying party shall not, without the prior written consent of
each indemnified party, settle, compromise or consent to the entry of any
judgment in any pending or threatened claim, action, suit or proceeding in
respect of which indemnity may be sought hereunder (whether or not such
indemnified party or any person who controls such indemnified party within the
meaning of the 1933 Act is a party to such claim, action, suit or proceeding),
unless such settlement, compromise or consent includes a release of each such
indemnified party reasonably satisfactory to each such indemnified party and
each such controlling person from all liability arising out of such claim,
action, suit or proceeding or unless the indemnifying party shall confirm in a
written agreement of the indemnifying party to each indemnified party, that
notwithstanding any federal, state or common law, such settlement, compromise or
consent shall not alter the right of any indemnified party or controlling person
to indemnification or contribution as provided in this Agreement.

         (d) If the indemnification provided for in this Section 7 is
unavailable or insufficient to hold harmless an indemnified party under
paragraphs (a), (b) or (c) hereof in respect of any losses, claims, damages,
liabilities or expenses referred to therein, then each indemnifying party, in
lieu of indemnifying such indemnified party, shall contribute to the amount paid
or payable by such indemnified party as a result of such losses, claims,
damages, liabilities or expenses (i) in such proportion as is appropriate to
reflect the relative benefits received by the Company on the one hand and the
Underwriters on the other from the offering of the Shares or (ii) if the
allocation provided by clause (i) above is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause (i) above but also the relative fault of the Company on
the one hand and the Underwriters on the other in connection with the statements
or omissions that resulted in such losses, claims, damages, liabilities or
expenses, as well as any other relevant equitable considerations. The relative
benefits received by the Company on the one hand and the Underwriters on the
other shall be deemed to be allocated pro rata on the basis of the total
underwriting discounts, commissions and compensation received by the
Underwriters relative to the total net proceeds from the offering of the Shares
(before deducting expenses) received by the Company, in each case as set forth
in the table on the cover page of the Prospectus. The relative fault of the
Company on the one hand and of the Underwriters on the other shall be determined
by reference to, among other things, whether the untrue or alleged untrue
statement of or the omission or alleged omission to state a fact relates to
information supplied by the Company or by the Underwriters and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such untrue statement or omission. The Company and the Underwriters
agree that it would not be just and equitable if contribution pursuant to this
paragraph (e) were determined by pro rata allocation (even if the Underwriters
were treated as one entity for such purpose) or by any other method of
allocation that does not take into account the equitable considerations referred
to herein. The amount paid or payable by an indemnified party as a result of the
losses, claims, damages, liabilities and expenses referred to in the first
sentence of this paragraph (e) shall be deemed to include, subject to the
limitations set forth above, any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any such
action or claim. Notwithstanding the provisions of this paragraph (e), no
Underwriter shall be required to contribute any amount in excess of the amount
by which the total price at which the Shares underwritten by such Underwriter
and distributed to the public were offered to the public exceeds the amount of
any damages that such Underwriter has otherwise been required to pay by reason
of such untrue or alleged untrue statement or omission or alleged omission. No
person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the 1933 Act) shall be entitled to contribution from any person who was
not guilty of such fraudulent misrepresentation.

                                       32


         For purposes of this paragraph (e), each person who controls an
Underwriter within the meaning of the 1933 Act shall have the same rights to
contribution as such Underwriter, and each person who controls the Company
within the meaning of the 1933 Act, each officer of the Company who shall have
signed the Registration Statement and each director of the Company shall have
the same rights to contribution as the Company, subject in each case to the
preceding paragraph. The Underwriters' obligations in this paragraph (e) to
contribute are several in proportion to their respective underwriting
obligations and not joint. The obligations of the Company under this paragraph
(e) shall be in addition to any liability which the Company may otherwise have
and the obligations of the Underwriters under this paragraph (e) shall be in
addition to any liability that the respective Underwriters may otherwise have.

         (e) The indemnity and contribution agreements contained in this Section
7 and the representations and warranties of the Company set forth in this
Agreement shall remain operative and in full force and effect, regardless of (i)
any investigation made by or on behalf of any Underwriter or any person
controlling any Underwriter or by or on behalf of the Company, or such
directors, trustees or officers (or any person controlling the Company), (ii)
acceptance of any Shares and payment therefor hereunder and (iii) any
termination of this Agreement. A successor of any Underwriter or of the Company,
such directors, trustees or officers (or of any person controlling any
Underwriter, the Company) shall be entitled to the benefits of the indemnity,
contribution and reimbursement agreements contained in this Section 7.

         8. Termination. You shall have the right to terminate this Agreement on
behalf of the Underwriters at any time at or prior to the Closing Date or, with
respect to the Underwriters' obligation to purchase the Option Shares, at any
time at or prior to the Option Closing Date, without liability on the part of
any Underwriter to the Company, if:

         (a) the Company shall have failed, refused, or been unable to perform
any agreement on its part to be performed under this Agreement, or any of the
conditions referred to in Section 6 shall not have been fulfilled, when and as
required by this Agreement;

         (b) The Company or any of the Subsidiaries shall have sustained any
loss or interference with its business from fire, explosion, flood or other
calamity, whether or not covered by insurance, or from any labor dispute or
court or governmental action, order or decree which in the judgment of the
Representatives impairs the investment quality of the Shares;

         (c) There has been since the respective dates as of which information
is given in the Registration Statement or the Prospectus, any adverse change in,
or any development which is likely to have an adverse effect on, the condition
(financial or otherwise), earnings, affairs, business, prospects or results of
operations of the Company and the Subsidiaries on a consolidated basis, whether
or not arising in the ordinary course of business;

         (d) There has occurred any outbreak of hostilities or other calamity or
crisis or change in general economic, political or financial conditions, or
internal conditions, the effect of which on the financial markets of the United
States is such as to make it, in your reasonable judgment, impracticable to
market the Shares or enforce contracts for the sale of the Shares;

                                       33


         (e) Trading generally on the New York Stock Exchange, the American
Stock Exchange or the Nasdaq National Market shall have been suspended, or
minimum or maximum prices for trading shall have been fixed, or maximum ranges
for prices for securities shall have been required, by any of said exchanges or
market system or by the Commission or any other governmental authority;

         (f) A banking moratorium shall have been declared by either federal or
Oklahoma authorities; or

         (g) Any action shall have been taken by any government in respect of
its monetary affairs which, in your reasonable judgment, has an adverse effect
on the United States securities markets.

         If this Agreement shall be terminated pursuant to this Section 8, the
Company shall not then be under any liability to any Underwriter except as
provided in Sections 5 and 7 hereof.

         9. Default of Underwriters. If any Underwriter or Underwriters shall
default in its or their obligations to purchase Shares hereunder, the other
Underwriters shall be obligated severally, in proportion to their respective
commitments hereunder, to purchase the Shares which such defaulting Underwriter
or Underwriters agreed but failed to purchase; provided, however, that the
non-defaulting Underwriters shall be under no obligation to purchase such Shares
if the aggregate number of Shares to be purchased by such non-defaulting
Underwriters shall exceed 110% of the aggregate underwriting commitments set
forth in Schedule I hereto, and provided further, that no non-defaulting
Underwriter shall be obligated to purchase Shares to the extent that the number
of such Shares is more than 110% of such Underwriter's underwriting commitment
set forth in Schedule I hereto.

         In the event that the non-defaulting Underwriters are not obligated
under the above paragraph to purchase the Shares which the defaulting
Underwriter or Underwriters agreed but failed to purchase, the Representatives
may in their discretion arrange for one or more of the Underwriters or for
another party or parties to purchase such Shares on the terms contained herein.
If within one business day after such default the Representatives do not arrange
for the purchase of such Shares, then the Company shall be entitled to a further
period of one business day within which to procure another party or parties
satisfactory to the Representatives to purchase such Shares on such terms.

         In the event that the Representatives or the Company do not arrange for
the purchase of any Shares to which a default relates as provided above, this
Agreement shall be terminated.

         If the remaining Underwriters or substituted underwriters are required
hereby or agree to take up all or a part of the Shares of a defaulting
Underwriter or Underwriters as provided in this Section 9, (i) you shall have
the right to postpone the Closing Date for a period of not more than five full
business days, in order to effect any changes that, in the opinion of counsel to
the Underwriters or the Company, may thereby be made necessary in the
Registration Statement or the Prospectus, or in any other documents or
agreements, and the Company agrees promptly to file any amendments to the
Registration Statement or supplements to the Prospectus which, in its opinion,
may thereby be made necessary and (ii) the respective numbers of Shares to be
purchased by the remaining Underwriters or substituted underwriters shall be
taken as the basis of their underwriting obligation for all purposes of this
Agreement. Nothing herein contained shall relieve any defaulting Underwriter of
any liability it may have for damages occasioned by its default hereunder. Any
termination of this Agreement pursuant to this Section 9 shall be without
liability on the part of any non-defaulting Underwriter or the Company, except
for expenses to be paid or reimbursed pursuant to Section 5 and except for the
provisions of Section 7.

         10. Effective Date of Agreement. If the Registration Statement is not
effective at the time of execution of this Agreement, this Agreement shall
become effective on the Effective Date at the time the Commission declares the
Registration Statement effective. The Company shall immediately notify the
Representatives when the Registration Statement becomes effective.

                                       34


         If the Registration Statement is effective at the time of execution of
this Agreement, this Agreement shall become effective at the earlier of 11:00
a.m. St. Louis time, on the first full business day following the day on which
this Agreement is executed, or at such earlier time as the Representatives shall
release the Shares for public offering. The Representatives shall notify the
Company immediately after it has taken any action which causes this Agreement to
become effective.

         Until such time as this Agreement shall have become effective, it may
be terminated by the Company, by notifying you, or by you, as Representatives of
the Underwriters, by notifying the Company, except that the provisions of
Sections 5 and 7 shall at all times be effective.

         11. Representations, Warranties and Agreements to Survive Delivery. The
representations, warranties, indemnities, agreements and other statements of the
Company and its officers set forth in or made pursuant to this Agreement and the
agreements of the Underwriters contained in Section 7 hereof shall remain
operative and in full force and effect regardless of any investigation made by
or on behalf of the Company or controlling persons of the Company, or by or on
behalf of the Underwriters or controlling persons of any Underwriters or any
termination or cancellation of this Agreement and shall survive delivery of and
payment for the Shares.

         12. Notices. Except as otherwise provided in this Agreement, all
notices and other communications hereunder shall be in writing and shall be
deemed to have been duly given if delivered by hand, mailed by registered or
certified mail, return receipt requested, or transmitted by any standard form of
telecommunication and confirmed. Notices to the Company shall be sent to 608
South Main Street, Stillwater, Oklahoma 74074, Attention: Rick J. Green (with a
copy to Kennedy & Baris, L.L.P., 4701 Sangamore Road, Bethesda, Maryland 20816,
Attention: Noel Gruber, Esq. and James I. Lundy III, Esq., 1700 Pennsylvania
Avenue, NW, Suite 400, Washington, D.C. 20006); and notices to the Underwriters
shall be sent to Stifel, Nicolaus & Company, Incorporated, 501 North Broadway,
9th Floor, St. Louis, Missouri 63102, Attention: Rick E. Maples (with a copy to
Bryan Cave LLP, 211 North Broadway, Suite 3600, St. Louis, Missouri 63102,
Attention: Harold R. Burroughs, Esq.). In all dealings with the Company under
this Agreement, Stifel, Nicolaus & Company, Incorporated shall act as
representative of and on behalf of the several Underwriters, and the Company
shall be entitled to act and rely upon any statement, request, notice or
agreement on behalf of the Underwriters, made or given by Stifel, Nicolaus &
Company, Incorporated on behalf of the Underwriters, as if the same shall have
been made or given in writing by the Underwriters.

         13. Parties. The Agreement herein set forth is made solely for the
benefit of the Underwriters, the Company and, to the extent expressed, directors
and officers of the Company, any person controlling the Company or any
Underwriter, and their respective successors and assigns. No other person shall
acquire or have any right under or by virtue of this Agreement. The term
"successors and assigns" shall not include any purchaser, in his status as such
purchaser, from any Underwriter of the Shares.

         14. Governing Law. This Agreement shall be governed by the laws of the
State of Missouri, without giving effect to the choice of law or conflicts of
law principles thereof.

         15. Counterparts. This Agreement may be executed in one or more
counterparts, and when a counterpart has been executed by each party hereto all
such counterparts taken together shall constitute one and the same Agreement.

                                       35


         16. Entire Agreement. This Agreement is intended by the parties as a
final expression of their agreement regarding the purchase and sale of Shares
and intended by be a complete and exclusive statement of the agreement and
understanding of the parties hereto in respect of the subject matter contained
herein.

         If the foregoing is in accordance with your understanding of our
agreement, please sign and return to us a counterpart hereof, whereupon this
shall become a binding agreement among the Company and you in accordance with
its terms.

                                                     Very truly yours,

                                                     Southwest Bancorp, Inc.

                                                     By: _______________________
                                                         Rick J. Green
                                                         Chief Executive Officer

Confirmed and accepted, as of the date first above written.

Stifel, Nicolaus & Company, Incorporated
Edward D. Jones & Co. L.L.P.
Friedman, Billings, Ramsey & Co., Inc.
Keefe, Bruyette & Woods, Inc.
Suntrust Capital Markets, Inc.

By:  Stifel, Nicolaus & Company, Incorporated

By:  ________________________
     Rick E. Maples
     Senior Managing Director

For itself and as Representatives
of the several Underwriters named in
Schedule I hereto.


                                       36



2070024
                                    Exhibit A
                                  Subsidiaries

                                                                 JURISDICTION OF
                               NAME                               INCORPORATION
- -----------------------------------------------------------      ---------------
SBI Capital Trust                                                  Delaware
OKSB Statutory Trust I                                             Connecticut
SBI Capital Trust II                                               Delaware
Business Consulting Group, Inc.                                    Oklahoma
Healthcare Strategic Support, Inc.                                 Oklahoma
SNB Bank of Wichita                                                United States
Stillwater National Bank and Trust Company                         United States
     Cash Source, Inc.*                                            Oklahoma
     CRK Properties, Inc.*                                         Oklahoma
         BNS, Inc.**                                               Oklahoma
     SWB, Inc.*                                                    Oklahoma
     SNB Insurance Agency, Inc.*                                   Oklahoma
     SNB Real Estate Holdings, Inc.*                               Delaware
         SNB REIT, Inc.***                                         Delaware
     Stillwater National Building Corporation*                     Oklahoma
         Stillwater Properties, Inc.****                           Oklahoma
              Grand Hill Investments, LLC*****                     Oklahoma

- --------------------

*        Direct subsidiary of Stillwater National Bank and Trust Company

**       Direct subsidiary of CRK Properties, Inc.

***      Direct subsidiary of SNB Real Estate Holdings, Inc.

****     Direct subsidiary of Stillwater National Building Corporation

*****    Direct subsidiary of Stillwater Properties, Inc.






2070024
                                   Schedule I
                                  Underwriters

                                                                 NUMBER OF FIRM
                                                                  SHARES TO BE
                    NAME OF UNDERWRITER                             PURCHASED
- ---------------------------------------------------------        --------------
Stifel, Nicolaus & Company, Incorporated.................
Edward D. Jones & Co. L.L.P..............................
Freidman, Billings, Ramsey & Co., Inc....................
Keefe Bruyette & Woods, Inc..............................
SunTrust Capital Markets, Inc............................
                                                                 --------------
         Total                                                      2,100,000
                                                                 ==============






                                   Schedule II
              List of Persons to Provide 90-Day Lock-Up Agreements

Directors:

James E. Berry II
Thomas D. Berry
Joe Berry Cannon
J. Berry Harrison
Erd M. Johnson
David P. Lambert
Linford R. Pitts
Robert B. Rodgers
Russell W. Teubner

Officers (all officers that are Section 16 reporting persons):

Kerby E. Crowell
L. Allen Glenn
Steven M. Gobel
Rick Green
Steven N. Hadley
Rex E. Horning
Jerry L. Lanier
Len McLaughlin
J. Randall Mills
Steven M. Peterson
Joseph P. Root
Kimberly G. Sinclair
Charles H. Westerheide
David L. York







                                   Schedule II
           List of Other Persons to Provide 90-Day Lock-Up Agreements

Joyce C. Berry Revocable Trust
Joe M. Berry Trust
BKP, L.L.C.
Berry Charitable Remainder Trust
Betty B. Kerns

EX-23.(A)

                                                                   Exhibit 23(a)

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM


We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3, No. 333-124502) and the related Prospectus of
Southwest Bancorp, Inc. for the registration of 2,415,000 shares of its common
stock and to the incorporation by reference therein to our reports dated March
14, 2005 with respect to the consolidated financial statements of Southwest
Bancorp, Inc., Southwest Bancorp, Inc. management's assessment of the
effectiveness of internal control over financial reporting, and the
effectiveness of internal control over financial reporting of Southwest Bancorp
included in its Annual Report (Form 10-K) for the year ended December 31, 2004,
filed with the Securities and Exchange Commission.


/s/ Ernst & Young, LLP


Tulsa, Oklahoma
May 17, 2005