10,500,000 Shares Pioneer Drilling Company Common Stock, $0.10 Per Share Par Value UNDERWRITING AGREEMENT

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Exhibit 1.1

10,500,000 Shares

Pioneer Drilling Company

Common Stock, $0.10 Per Share Par Value

UNDERWRITING AGREEMENT

                        , 2005

JEFFERIES & COMPANY, INC.
RAYMOND JAMES & ASSOCIATES
JOHNSON RICE & COMPANY L.L.C.
PRITCHARD CAPITAL PARTNERS, LLC
c/o JEFFERIES & COMPANY, INC.
520 Madison Avenue, 12 ^th Floor
New York, New York 10022

Ladies and Gentlemen:

        Pioneer Drilling Company, a Texas corporation (the " Company "), proposes to issue and sell to the several underwriters named in Schedule A (the " Underwriters ") an aggregate of 5,000,000 shares of its common stock, par value $0.10 per share (" Common Stock "); and the shareholders of the Company named in Schedule B (collectively, the " Selling Shareholders "), propose to sell to the Underwriters an aggregate of 5,500,000 shares of Common Stock. The 5,000,000 shares of Common Stock to be sold by the Company and the 5,500,000 shares of Common Stock to be sold by the Selling Shareholders are collectively called the " Firm Shares ." In addition, the Company has granted to the Underwriters an option to purchase up to an additional 787,500 shares of Common Stock and one of the Selling Shareholders, WEDGE Energy Services, L.L.C. (" WEDGE "), has granted to the Underwriters an option to purchase up to an additional 787,500 shares of Common Stock, all as provided in Section 2. The additional 787,500 shares of Common Stock to be sold by the Company and the additional 787,500 shares of Common Stock to be sold by WEDGE pursuant to such option are collectively called the " Optional Shares ." The Firm Shares and, if and to the extent such option is exercised, the Optional Shares are collectively called the " Offered Shares ." Jefferies & Company, Inc. (" Jefferies ") has agreed to act as representative of the several Underwriters (in such capacity, the " Representative ") in connection with the offering and sale of the Offered Shares.

        The Company has prepared and filed with the Securities and Exchange Commission (the " Commission ") a registration statement on Form S-1 (Reg. No. 333-            ), which contains a form of prospectus to be used in connection with the public offering and sale of the Offered Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, in the form in which it was declared effective by the Commission under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the " Securities Act "), including any information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430A under the Securities Act, is called the " Registration Statement ." Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the " Rule 462(b) Registration Statement, " and from and after the date and time of filing of the Rule 462(b) Registration Statement, the term " Registration Statement " shall include the Rule 462(b) Registration Statement. Such prospectus, in the form first used by the Underwriters to confirm sales of the Offered Shares, is called the " Prospectus ". All references in this Agreement to (i) the Registration Statement, the Rule 462(b) Registration Statement, a preliminary prospectus, or the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis, and Retrieval system (" EDGAR ") and (ii) the Prospectus shall be deemed to include the " electronic Prospectus " provided for use in connection with the offering of the Offered Shares as contemplated by Section 3(A)(k) of this Agreement.

        The Company and the Selling Shareholders hereby confirm their respective agreements with the Underwriters as follows:

Section 1.    Representations and Warranties .

        A.    Representations and Warranties of the Company.     The Company hereby represents, warrants and covenants to each Underwriter as follows:

        (a)     Compliance with Registration Requirements .    The Registration Statement and any Rule 462(b) Registration Statement have been declared effective by the Commission under the Securities Act. No stop order suspending the effectiveness of the Registration Statement or any Rule 462(b) Registration Statement is in effect and no proceedings for such purpose have been instituted or are pending or, to the knowledge of the Company, are contemplated or threatened by the Commission. When used herein, the term "knowledge of the Company" or similar terms, means the actual knowledge of Wm. Stacy Locke, William D. Hibbetts, Franklin C. West, Donald G. Lacombe and Michael E. Little.

        Each preliminary prospectus and the Prospectus when filed complied in all material respects with the Securities Act and, if filed by electronic transmission pursuant to EDGAR (except as may be permitted by Regulation S-T under the Securities Act), was identical to the copy thereof delivered to the Underwriters for use in connection with the offer and sale of the Offered Shares. Each of the Registration Statement, any Rule 462(b) Registration Statement and any post-effective amendment thereto, at the time it became effective, complied in all material respects with the Securities Act and did not and will not, as of its effective date, 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 statements therein not misleading. The Prospectus, as amended or supplemented, as of its date and as of the First Closing Date and the Option Closing Date (if applicable), did not and will not contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The representations and warranties set forth in the two immediately preceding sentences do not apply to statements in or omissions from the Registration Statement, any Rule 462(b) Registration Statement, or any post-effective amendment thereto, or the Prospectus, or any amendments or supplements thereto, made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by the Representative expressly for use therein, it being understood and agreed that the only such information furnished by the Representative to the Company consists of the information described in Section 8(b) below. There are no contracts or other documents required to be described in the Prospectus or to be filed as exhibits to the Registration Statement which have not been described or filed as required.

        (b)     Offering Materials Furnished to Underwriters .    The Company has delivered to the Representative one complete manually signed copy of the Registration Statement and of each consent and certificate of experts filed as a part thereof, and conformed copies of the Registration Statement (without exhibits) and preliminary prospectuses and the Prospectus, as amended or supplemented, in such quantities and at such places as the Representative has reasonably requested for each of the Underwriters.

        (c)     Distribution of Offering Material By the Company .    The Company has not distributed and will not distribute, prior to the later of (i) the expiration or termination of the option granted to the several Underwriters in Section 2 and (ii) the completion of the Underwriters' distribution of the Offered Shares, any offering material in connection with the offering and sale of the Offered Shares other than a preliminary prospectus, the Prospectus, the Registration Statement or other materials, if any, permitted by the Securities Act.

        (d)     The Underwriting Agreement .    This Agreement has been duly authorized, executed and delivered by, and is a valid and binding agreement of, the Company, enforceable in accordance with its

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terms, except as rights to indemnification hereunder may be limited by applicable law and except as the enforcement hereof may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

        (e)     Authorization of the Offered Shares.     The Offered Shares to be purchased by the Underwriters from the Company have been duly authorized for issuance and sale pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement, will be validly issued, fully paid and nonassessable.

        (f)     No Applicable Registration or Other Similar Rights.     There are no persons with registration or other similar rights to have any equity or debt securities registered for sale under the Registration Statement or included in the offering contemplated by this Agreement, other than the Selling Shareholders with respect to the Offered Shares included in the Registration Statement and such rights as have been duly waived in writing.

        (g)     No Material Adverse Effect.     Except as otherwise disclosed in the Prospectus, subsequent to December 31, 2004: (i) there has been no material adverse change, event or any development that would reasonably be expected to have a material adverse effect on the condition, financial or otherwise, or on the earnings, business or operations, whether or not arising from transactions in the ordinary course of business, of the Company and its subsidiaries, considered as one entity (any such effect is called a " Material Adverse Effect "); (ii) the Company and its subsidiaries, considered as one entity, have not incurred any material liability or obligation (including any off-balance sheet obligation), indirect, direct or contingent, not in the ordinary course of business nor entered into any material transaction or agreement not in the ordinary course of business; and (iii) there has been no dividend or distribution of any kind declared, paid or made by the Company or, except for dividends paid to the Company or other subsidiaries, any of its subsidiaries on any class of capital stock (or partnership interest) or repurchase or redemption by the Company or any of its subsidiaries of any class of capital stock (or partnership interest).

        (h)     Independent Accountants.     KPMG LLP, who have expressed their opinion with respect to the financial statements (which term as used in this Agreement includes the related notes thereto) and supporting schedules of the Company filed with the Commission as a part of the Registration Statement and included in the Prospectus, are (i) independent public or certified public accountants as required by the Securities Act and the Securities Exchange Act of 1934, and the rules and regulations promulgated thereunder (the " Exchange Act "), and (ii) a registered public accounting firm as defined by the Public Company Accounting Oversight Board (the " PCAOB ") whose registration has not been suspended or revoked and who has not requested such registration to be withdrawn. Brady, Martz & Associates, P.C., who have expressed their opinion with respect to the financial statements and supporting schedules of Wolverine Drilling, Inc. (" Wolverine ") filed with the Commission as a part of the Registration Statement and included in the Prospectus, are (i) independent public or certified public accountants as required by the Securities Act and the Exchange Act, and (ii) a registered public accounting firm as defined by the PCAOB whose registration has not been suspended or revoked and who has not requested such registration to be withdrawn Kennedy and Coe, LLC, who have expressed their opinion with respect to the financial statements and supporting schedules of Allen Drilling Company (" Allen ") filed with the Commission as a part of the Registration Statement and included in the Prospectus, are independent public or certified public accountants as required by the Securities Act and the Exchange Act.

        (i)     Preparation of the Financial Statements.     The financial statements filed with the Commission as a part of the Registration Statement and included in the Prospectus present fairly the consolidated financial position of the Company and its subsidiaries, and the financial position of each of Wolverine and Allen, as of the dates indicated therein and each of the foregoing entities' results of operations and

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cash flows for the periods specified therein. The supporting schedules included in the Registration Statement present fairly the information required to be stated therein. Such financial statements and supporting schedules have been prepared in conformity with generally accepted accounting principles as applied in the United States applied on a consistent basis throughout the periods involved, except as may be expressly stated in the related notes thereto. No other financial statements or supporting schedules are required to be included in the Registration Statement. The pro forma financial statements filed with the Commission as a part of the Registration Statement and included in the Prospectus give appropriate effect to the assumptions used in the preparation thereof; those assumptions are reasonable and the adjustments used in such pro forma financial statements are appropriate to give effect to the transactions or circumstances referred to therein; and such pro forma financial statements comply as to form with the requirements applicable to pro forma financial statements included in registration statements on Form S-1 under the Securities Act and have been prepared on a basis consistent with the consolidated historical financial statements of the Company and its subsidiaries (except as otherwise indicated therein). The financial data set forth in the Prospectus under the captions "Prospectus Summary—Summary Financial Data," "Selected Financial Data", "Supplementary Financial Information" and "Capitalization" fairly present the information set forth therein on a basis consistent with that of the audited financial statements contained in the Registration Statement. To the knowledge of the Company, no person who has been suspended or barred from being associated with a registered public accounting firm, or who has failed to comply with any sanction pursuant to Rule 5300 promulgated by the PCAOB, has participated in or otherwise aided the preparation of, or audited, the financial statements, supporting schedules or other financial data filed with the Commission as a part of the Registration Statement and included in the Prospectus.

        (j)     Company's Accounting System.     The Company makes and keeps accurate books and records and maintains a system of accounting controls sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management's general or specific authorization; (ii)  transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles as applied in the United States and to maintain accountability for assets; (iii) access to assets is permitted only in accordance with management's general or specific authorization; and (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

        (k)     Incorporation and Good Standing of the Company and its Subsidiaries.     Each of the Company and its subsidiaries has been duly incorporated and is validly existing as a corporation, partnership or limited liability company, as applicable, in good standing under the laws of the jurisdiction of its incorporation or organization and has the power and authority (corporate or other) to own, lease and operate its properties and to conduct its business in all material respects as described in the Prospectus and, in the case of the Company, to enter into and perform its obligations under this Agreement. Each of the Company and its subsidiaries is duly qualified as a foreign corporation, partnership or limited liability company, as applicable, to transact business and is in good standing in the State of Texas and each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure to be so qualified would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. All of the issued and outstanding capital stock or other equity or ownership interest of each subsidiary has been duly authorized and validly issued, is fully paid and nonassessable and is owned by the Company, directly or through subsidiaries, free and clear of any security interest, mortgage, pledge, lien, encumbrance or adverse claim, except as would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. None of the issued and outstanding shares of capital stock or other equity or ownership interest of any subsidiary of the Company were issued in violation of preemptive or other similar rights of any security holder of such subsidiary. The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Exhibit 21.1 to the Registration Statement. Each of South Texas Drilling Company,

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a Texas Corporation, South Texas Offshore Drilling Company, a Texas corporation, and ST/1200, Inc., a Texas corporation, is a wholly owned subsidiary of the Company (each an "Inactive Subsidiary "). Each Inactive Subsidiary does not carry on any business, does not conduct any operations and has no material assets. The Company does not own, lease or license any material asset or property or conduct any material business outside of the United States of America.

        (l)     Capitalization and Other Capital Stock Matters.     The authorized, issued and outstanding capital stock of the Company is as set forth in the Prospectus under the caption "Capitalization" (other than for subsequent issuances, if any, pursuant to the Company's employee benefit plans described or referred to in the Prospectus or upon exercise of outstanding options or warrants described in and existing on the date of the Prospectus). The shares of Common Stock (including the Offered Shares) conform in all material respects to the description thereof contained in the Prospectus. All of the issued and outstanding shares of Common Stock (including the shares of Common Stock owned by the Selling Shareholders) have been duly authorized and validly issued, are fully paid and nonassessable and have been issued in compliance with federal and state securities laws. None of the outstanding shares of Common Stock were issued in violation of any preemptive rights, rights of first refusal or other similar rights to subscribe for or purchase securities of the Company. There are no authorized or outstanding options, warrants, preemptive rights, rights of first refusal or other rights to purchase, or equity or debt securities convertible into or exchangeable or exercisable for, any capital stock of the Company or any of its subsidiaries other than those described in the Prospectus or such rights as have been duly waived in writing. The description of the Company's stock option, stock bonus and other stock plans or arrangements, and the options or other rights granted thereunder, set forth in the Prospectus accurately and fairly presents the information required to be shown with respect to such plans, arrangements, options and rights. Except as described in the Prospectus, the Company has not sold or issued any shares of Common Stock during the six-month period preceding the date of the Prospectus, including any sales pursuant to Rule 144A under, or Regulations D or S of, the Securities Act other than shares of Common Stock issued pursuant to employee benefit plans, qualified stock options plans or other employee compensation plans or pursuant to outstanding options, rights or warrants.

        (m)     Stock Exchange Listing.     The Common Stock is registered pursuant to Section 12(b) of the Exchange Act and listed on the American Stock Exchange, and the Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Common Stock under the Exchange Act or delisting the Common Stock from the American Stock Exchange, nor has the Company received any notification that the Commission or the American Stock Exchange is contemplating terminating such registration or listing.

        (n)     Non-Contravention of Existing Instruments; No Further Authorizations or Approvals Required.     Neither the Company nor any of its subsidiaries is in violation of its charter or by-laws or is in default (or, with the giving of notice or lapse of time, would be in default) (" Default ") under any indenture, mortgage, loan or credit agreement, note, contract, franchise, lease or other instrument to which the Company or any of its subsidiaries is a party or by which it or any of them may be bound, or to which any of the property or assets of the Company or any of its subsidiaries is subject (each, an " Existing Instrument "), except for such Defaults as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The Company's execution, delivery and performance of this Agreement, consummation of the transactions contemplated hereby and by the Prospectus and the issuance and sale of the Offered Securities (i) have been duly authorized by all necessary corporate action and will not result in any violation of the provisions of the charter or by-laws of the Company or any subsidiary, (ii) will not conflict with or constitute a breach of, or Default or a Debt Repayment Triggering Event (as defined below) under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, or require the consent of any other party to, any Existing Instrument and (iii) will not result in any

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violation of any law, administrative regulation or administrative or court decree applicable to the Company or any subsidiary, except in the case of (ii) and (iii) above, where such conflict, breach, Default, Debt Repayment Triggering Event, lien, charge, encumbrance, consent or violation would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. No consent, approval, authorization or other order of, or registration or filing with, any court or other governmental or regulatory authority or agency, is required for the Company's execution, delivery and performance of this Agreement and consummation of the transactions contemplated hereby and by the Prospectus, except such as have been obtained or made by the Company and are in full force and effect under the Securities Act, applicable state securities or blue sky laws. As used herein, a " Debt Repayment Triggering Event " means any event or condition which gives, or with the giving of notice or lapse of time would give, the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder's behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

        (o)     No Material Actions or Proceedings.     Except as otherwise disclosed in the Prospectus, there are no legal or governmental actions, suits or proceedings pending or, to the knowledge of the Company, threatened (i) against or affecting the Company or any of its subsidiaries, (ii) which has as the subject thereof any officer or director of, or property owned or leased by, the Company or any of its subsidiaries or (iii) relating to environmental or discrimination matters, where in any such case there is a reasonable possibility that such action, suit or proceeding might be determined adversely to the Company, such subsidiary or such officer or director, and (A) any such action, suit or proceeding, if so determined adversely, would reasonably be expected to have a Material Adverse Effect or adversely affect the consummation of the transactions contemplated by this Agreement or (B) any such action, suit or proceeding is or would be material in the context of the sale of the Offered Shares. No material labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is threatened or imminent.

        (p)     Intellectual Property Rights.     The Company and its subsidiaries own or possess sufficient trademarks, trade names, patent rights, copyrights, domain names, licenses, approvals, trade secrets and other similar rights (collectively, " Intellectual Property Rights ") reasonably necessary to conduct their businesses as now conducted, except for such failures to own such Intellectual Property Rights as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and the expected expiration of any of such Intellectual Property Rights would not reasonably be expected to have a Material Adverse Effect. Neither the Company nor any of its subsidiaries has received, or has any reason to believe that it will receive, any notice of infringement or conflict with asserted Intellectual Property Rights of others, except for any such infringements or conflicts as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The Company is not a party to or bound by any material options, licenses or agreements with respect to the Intellectual Property Rights of any other person or entity that are required to be set forth in the Prospectus and are not described therein. None of the technology employed by the Company has been obtained or is being used by the Company in violation of any contractual obligation binding on the Company or, to the Company's knowledge, any of its officers, directors or employees or otherwise in violation of the rights of any persons, except for any such violations as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

        (q)     All Necessary Permits, etc.     (i) The Company and each subsidiary possess such valid and current certificates, authorizations or permits issued by the appropriate state, federal or foreign regulatory agencies or bodies necessary to conduct their respective businesses, except where the failure to possess such valid and current certificates, authorizations or permits would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect, and (ii) neither the Company nor any subsidiary has received, or has any reason to believe that it will receive, any notice of proceedings relating to the revocation or modification of, or non-compliance with, any such certificate,

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authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would reasonably be expected to have a Material Adverse Effect.

        (r)     Title to Properties.     The Company and each of its subsidiaries has good and indefeasible title with respect to all real property and good and valid title to all properties and other assets (other than real property) reflected as owned in the financial statements referred to in Section 1(A)(i) above (or elsewhere in the Prospectus), in each case free and clear of any security interests, mortgages, liens, encumbrances, equities, adverse claims and other defects, except such as (i) do not materially and adversely affect the value of such property and do not materially interfere with the use made or proposed to be made of such property by the Company or such subsidiary or (ii) would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The real property, improvements, equipment and personal property held under lease by the Company or any subsidiary are held under valid and enforceable leases, with such exceptions as (i) are not material and do not materially interfere with the use made or proposed to be made of such real property, improvements, equipment or personal property by the Company or such subsidiary or (ii) would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

        (s)     Tax Law Compliance.     Except as would not reasonably be expected to have a Material Adverse Effect, the Company and its consolidated subsidiaries have filed all necessary federal, state and foreign income and franchise tax returns and have paid all taxes required to be paid by any of them and, if due and payable, any related or similar assessment, fine or penalty levied against any of them. The Company has made adequate charges, accruals and reserves in the applicable financial statements referred to in Section 1(A)(i) above in respect of all federal, state and foreign income and franchise taxes for all periods as to which the tax liability of the Company or any of its consolidated subsidiaries has not been finally determined, except as would not reasonably be expected to have a Material Adverse Effect.

        (t)     Company Not an "Investment Company".     The Company has been advised of the rules and requirements under the Investment Company Act of 1940, as amended (the " Investment Company Act "). The Company and each of its subsidiaries is not, and after receipt of payment for the Offered Shares will not be, an " investment company " within the meaning of Investment Company Act and is not, and after receipt of payment of the Offered Shares will not be, an entity "controlled" by and "investment company" within the meaning of the Investment Company Act.

        (u)     Insurance.     Each of the Company and its subsidiaries are insured by insurers of recognized responsibility with policies in such amounts and with such deductibles and covering such risks as management of the Company deems adequate. The Company has no reason to believe that it or any subsidiary will not be able (i) to renew its existing insurance coverage as and when such policies expire or (ii) to obtain comparable coverage from similar institutions as may be necessary or appropriate to conduct its business as now conducted and at a cost that would not reasonably be expected to have a Material Adverse Effect.

        (v)     No Price Stabilization or Manipulation; Compliance with Regulation M.     The Company has not taken, directly or indirectly, any action designed to or that might be reasonably expected to cause or result in stabilization or manipulation of the price of the Common Stock or any other " reference security " (as defined in Rule 100 of Regulation M under the 1934 Act ( "Regulation M" )) with respect to the Common Stock whether to facilitate the sale or resale of the Offered Shares or otherwise, and has taken no action which would directly or indirectly violate Regulation M.

        (w)     Related Party Transactions.     There are no business relationships or related-party transactions involving the Company or any subsidiary or any other person required to be described in the Prospectus which have not been described as required.

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        (x)     Disclosure Controls and Procedures; Deficiencies in or Changes to Internal Control Over Financial Reporting.     The Company has established and maintains disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)), which (i) are designed to ensure that material information relating to the Company, including its consolidated subsidiaries, is made known to the Company's principal executive officer and its principal financial officer by others within those entities, particularly during the periods in which the periodic reports required under the Exchange Act are being prepared; (ii) have been evaluated for effectiveness as of the end of the period covered by the Company's most recently filed annual or quarterly report which precedes the date of the Prospectus; and (iii) are effective in all material respects to perform the functions for which they were established. Based on the most recent evaluation of its disclosure controls and procedures, the Company is not aware of (i) any significant deficiencies or material weaknesses in the design or operation of internal control over financial reporting which 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 registrant's internal control over financial reporting. The Company is not aware of any change in its internal control over financial reporting that has occurred during its most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the Company's internal control over financial reporting.

        (y)     Compliance with Environmental Laws.     Except as described in the Prospectus and except as would not, singly or in the aggregate, reasonably be expected to have a Material Adverse Effect, (i) neither the Company nor any of its subsidiaries is in violation of any federal, state, local or foreign statute, law, rule, regulation, ordinance, code, policy or rule of common law or any judicial or administrative interpretation thereof, including any judicial or administrative order, consent, decree or judgment, relating to pollution or protection of human health, the environment (including, without limitation, ambient air, surface water, groundwater, land surface or subsurface strata) or wildlife, including, without limitation, laws and regulations relating to the release or threatened release of chemicals, pollutants, contaminants, wastes, toxic substances, hazardous substances, petroleum or petroleum products (collectively, "Hazardous Materials") or to the manufacture, processing, distribution, use, treatment, storage, disposal, transport or handling of Hazardous Materials (collectively, "Environmental Laws"), (ii) the Company and its subsidiaries have all permits, authorizations and approvals required under any applicable Environmental Laws and are each in compliance with their requirements, (iii) there are no pending or, to the knowledge of the Company, threatened administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, notices of noncompliance or violation, investigation or proceedings relating to any Environmental Law against the Company or any of its subsidiaries and (iv) to the knowledge of the Company, there are no events or circumstances that would reasonably be expected to form the basis of an order for clean-up or remediation, or an action, suit or proceeding by any private party or governmental body or agency, against or affecting the Company or any of its subsidiaries relating to Hazardous Materials or any Environmental Laws.

        (z)     ERISA Compliance.     The Company and its subsidiaries and any " employee benefit plan " (as defined under the Employee Retirement Income Security Act of 1974, as amended, and the regulations and published interpretations thereunder (collectively, " ERISA ")) established or maintained by the Company, its subsidiaries or their " ERISA Affiliates " (as defined below) are in compliance with ERISA, except where the failure to so comply would not reasonably be expected to have a Material Adverse Effect. " ERISA Affiliate " means, with respect to the Company or a subsidiary, any member of any group of organizations described in Sections 414(b),(c),(m) or (o) of the Internal Revenue Code of 1986, as amended, and the regulations and published interpretations thereunder (the " Code ") of which the Company or such subsidiary is a member. No " reportable event " (as defined under ERISA) has occurred or is reasonably expected to occur with respect to any " employee benefit plan " established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates. No " employee benefit

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plan " established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates, if such " employee benefit plan " were terminated, would have any " amount of unfunded benefit liabilities " (as defined under ERISA). Neither the Company, its subsidiaries nor any of their ERISA Affiliates has incurred or reasonably expects to incur any material liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any " employee benefit plan " or (ii) Sections 412, 4971, 4975 or 4980B of the Code. Each " employee benefit plan " established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates that is intended to be qualified under Section 401(a) of the Code is so qualified and, to the knowledge of the Company, nothing has occurred, whether by action or failure to act, which would cause the loss of such qualification.

        (aa)     Brokers.     Except as otherwise disclosed in the Prospectus, there is no broker, finder or other party that is entitled to receive from the Company any brokerage or finder's fee or other fee or commission as a result of any transactions contemplated by this Agreement.

        (bb)     No Outstanding Loans or Other Extensions of Credit.     Neither the Company nor any of its subsidiaries has extended or maintained credit, arranged for the extension of credit, or renewed any extension of credit, in the form of a personal loan, to or for any director or executive officer (or equivalent thereof) of the Company and/or such subsidiary except for such extensions of credit as are (i) expressly permitted by Section 13(k) of the Exchange Act or (ii) fully repaid, discharged, forgiven or otherwise no longer outstanding or owing in any way on the date of this Agreement.

        (cc)     Compliance with Laws.     Except as otherwise disclosed in the Prospectus, the Company has not been advised, and has no reason to believe, that it and each of its subsidiaries are not conducting business in compliance with all applicable laws, rules and regulations of the jurisdictions in which it is conducting business, including, without limitation, the Sarbanes-Oxley Act and the rules and regulations promulgated thereunder by the Commission, except where failure to be so in compliance would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect.

        The Company acknowledges that the Underwriters and, for purposes of the opinions to be delivered pursuant to Section 5 hereof, counsel to the Company and counsel to the Underwriters, will rely upon the accuracy and truthfulness of the foregoing representations and hereby consents to such reliance.

        B.    Representations and Warranties of the Selling Shareholders.     Each Selling Shareholder severally represents, warrants and covenants to each Underwriter as follows:

        (a)     The Underwriting Agreement.     This Agreement has been duly authorized, executed and delivered by or on behalf of such Selling Shareholder and is a valid and binding agreement of such Selling Shareholder, enforceable in accordance with its terms, except as rights to indemnification hereunder may be limited by applicable law and except as the enforcement hereof may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

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        (b)     The Power of Attorney.     The Power of Attorney appointing certain individuals named therein as Michael E. Little's attorneys-in-fact (each, an " Attorney-in-Fact ") to the extent set forth therein relating to the transactions contemplated hereby and by the Prospectus (the " Power of Attorney "), of Michael E. Little has been duly authorized, executed and delivered by Michael E. Little and is a valid and binding agreement of Michael E. Little, enforceable in accordance with its terms, except as rights to indemnification thereunder may be limited by applicable law and except as the enforcement thereof may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

        (c)     Title to Offered Shares to be Sold.     Such Selling Shareholder has, and on the First Closing Date and each applicable Option Closing Date (as defined below) will have, good and valid title to all of the Offered Shares which may be sold by such Selling Shareholder pursuant to this Agreement on such date and the legal right and power to sell, transfer and deliver all of the Offered Shares which may be sold by such Selling Shareholder pursuant to this Agreement and to comply with its other obligations hereunder and thereunder.

        (d)     Delivery of the Offered Shares to be Sold.     Delivery of the Offered Shares which are sold by such Selling Shareholder pursuant to this Agreement will pass good and valid title to such Offered Shares, free and clear of any security interest, mortgage, pledge, lien, encumbrance or other adverse claim.

        (e)     Non-Contravention; No Further Authorizations or Approvals Required.     The execution and delivery by such Selling Shareholder of, and the performance by such Selling Shareholder of its obligations under, this Agreement or the Power of Attorney will not contravene or conflict with, result in a breach of, or constitute a Default under, or require the consent of any other party to, the charter or by-laws, partnership agreement, trust agreement or other organizational documents of such Selling Shareholder or any other agreement or instrument to which such Selling Shareholder is a party or by which it is bound or under which it is entitled to any right or benefit, any provision of applicable law or any judgment, order, decree or regulation applicable to such Selling Shareholder of any court, regulatory body, administrative agency, governmental body or arbitrator having jurisdiction over such Selling Shareholder. No consent, approval, authorization or other order of, or registration or filing with, any court or other governmental authority or agency, is required for the consummation by such Selling Shareholder of the transactions contemplated in this Agreement, except such as have been obtained or made and are in full force and effect under the Securities Act, applicable state securities or blue sky laws and from the NASD.

        (f)     No Registration, Pre-emptive, Co-Sale or Other Similar Rights.     Such Selling Shareholder (i) does not have any registration or other similar rights to have any equity or debt securities registered for sale under the Registration Statement or included in the offering contemplated by this Agreement, except for such rights as are described in the Prospectus, (ii) does not have any preemptive right, co-sale right or right of first refusal or other similar right to purchase any of the Offered Shares that are to be sold by the Company or the other Selling Shareholder to the Underwriters pursuant to this Agreement, except for such rights as such Selling Shareholder has waived prior to the date hereof or as have been described in the Registration Statement and Prospectus, and (iii) does not own any warrants, options or similar rights to acquire, and does not have any right or arrangement to acquire, any capital stock, right, warrants, options or other securities from the Company, other than those disclosed in the Registration Statement and the Prospectus .

        (g)     No Further Consents, etc.     Except for such consents, approvals and waivers which have been obtained by such Selling Shareholder on or prior to the date of this Agreement, no consent, approval or waiver is required under any instrument or agreement to which such Selling Shareholder is a party or by which it is bound or under which it is entitled to any right or benefit, in connection with the

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offering, sale or purchase by the Underwriters of any of the Offered Shares which may be sold by such Selling Shareholder under this Agreement or the consummation by such Selling Shareholder of any of the other transactions contemplated hereby.

        (h)     Disclosure Made by such Selling Shareholder in the Prospectus.     All information furnished by or on behalf of such Selling Shareholder in writing expressly for use in the Registration Statement and Prospectus is, and on the First Closing Date and the applicable Option Closing Date will be, true, correct, and complete in all material respects, and does not, and on the First Closing Date and the applicable Option Closing Date will not, contain any untrue statement of a material fact or omit to state any material fact necessary to make such information not misleading. Such Selling Shareholder confirms as accurate the number of shares of Common Stock set forth opposite such Selling Shareholder's name in the Prospectus under the caption "Selling Shareholders" (both prior to and after giving effect to the sale of the Offered Shares).

        (i)     No Price Stabilization or Manipulation; Compliance with Regulation M.     Such Selling Shareholder has not taken, directly or indirectly, any action designed to or that might be reasonably expected to cause or result in stabilization or manipulation of the price of the Common Stock or any other reference security with respect to the Common Stock, whether to facilitate the sale or resale of the Offered Shares or otherwise, and has taken no action which would directly or indirectly violate any provision of Regulation M.

        (j)     No Transfer Taxes or Other Fees.     There are no transfer taxes or other similar fees or charges under Federal law or the laws of any state, or any political subdivision thereof, required to be paid in connection with the execution and delivery of this Agreement or the sale by the Selling Shareholders of the Offered Shares.

        (k)     Distribution of Offering Materials by the Selling Shareholders.     The Selling Shareholders have not distributed and will not distribute, prior to the later of (i) the expiration or termination of the option granted to the several Underwriters under Section 2 and (ii) the completion of the Underwriters' distribution of the Offered Shares, any offering material in connection with the offering and sale of the Offered Shares other than a preliminary prospectus, the Prospectus or the Registration Statement or other materials, if any, permitted by the Securities Act.

        (l)     Confirmation of Company Representations and Warranties.     Such Selling Shareholder is familiar with the Registration Statement and the Prospectus and has no knowledge of any material fact, condition or information not disclosed in the Registration Statement or the Prospectus which has had or would reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect and is not prompted to sell any of the Offered Shares by any material information concerning the Company which is not set forth in the Registration Statement and the Prospectus.

        Such Selling Shareholder acknowledges that the Underwriters and, for purposes of the opinion to be delivered pursuant to Section 5 hereof, counsel to WEDGE and counsel to the Underwriters, will rely upon the accuracy and truthfulness of the foregoing representations and hereby consents to such reliance.

Section 2.    Purchase, Sale and Delivery of the Offered Shares .

        (a)     The Firm Shares.     Upon the terms herein set forth, (i) the Company agrees to issue and sell to the several Underwriters an aggregate of 5,000,000 Firm Shares and (ii) the Selling Shareholders agree to sell to the several Underwriters an aggregate of 5,500,000 Firm Shares, with each Selling Shareholder selling the number of Firm Shares set forth opposite such Selling Shareholder's name on Schedule B . On the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, each Underwriter agrees, severally and not jointly, to purchase from the Company and the Selling Shareholders the respective number of Firm

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Shares set forth opposite its name on Schedule A . The purchase price per Firm Share to be paid by the several Underwriters to the Company and the Selling Shareholders shall be $             per share.

        (b)     The First Closing Date.     Delivery of the Firm Shares to be purchased by the Underwriters and payment therefor shall be made at the offices of Baker Botts, L.L.P., 910 Louisiana, Houston, Texas (or such other place as may be agreed to by the Company and the Representative) at 9:00 a.m. Houston time, on                        , 2005, or such other time and date not later than 12:30 p.m. Houston time, on [insert a date 10 business days following the original contemplated First Closing Date] as the Representative shall designate by notice to the Company (the time and date of such closing are called the " First Closing Date "). The Company and the Selling Shareholders hereby acknowledge that circumstances under which the Representative may provide notice to postpone the First Closing Date as originally scheduled include any determination by the Company, the Selling Shareholders or the Representative to recirculate to the public copies of an amended or supplemented Prospectus or a delay as contemplated by the provisions of Section 10. Upon the written request of Chesapeake Energy Corporation (" Chesapeake "), the Underwriters agree to allocate a percentage (or such lesser amount as may be requested by Chesapeake) of the Firm Shares to be sold by the Company equal to the percentage of the outstanding Common Stock held by Chesapeake (assuming the conversion of all outstanding convertible preferred stock or debt) on the First Closing Date (the " Chesapeake Firm Shares "), to the account of Chesapeake in accordance with Chesapeake's election to exercise the preemptive rights which it holds in connection with the Company's offering of those shares.

        (c)     The Optional Shares; Option Closing Date.     In addition, on the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Company and WEDGE hereby grant an option to the several Underwriters to purchase, severally and not jointly, up to an aggregate of 1,575,000 Optional Shares from the Company and WEDGE at the purchase price per share to be paid by the Underwriters for the Firm Shares. The option granted hereunder is for use by the Underwriters solely in covering any over-allotments in connection with the sale and distribution of the Firm Shares. The option granted hereunder may be exercised at any time and from time to time in whole or in part upon notice by the Representative to the Company and WEDGE, which notice may be given at any time within 30 days from the date of this Agreement. Such notice shall set forth (i) the aggregate number of Optional Shares as to which the Underwriters are exercising the option, (ii) the names and denominations in which the Optional Shares are to be registered and (iii) the time, date and place at which such Optional Shares will be delivered (which time and date may be simultaneous with, but not earlier than, the First Closing Date; and in such case the term " First Closing Date " shall refer to the time and date of delivery of certificates for the Firm Shares and such Optional Shares). Such time and date of delivery, if subsequent to the First Closing Date, is called an " Option Closing Date " and shall be determined by the Representative and shall not be earlier than three nor later than five full business days after delivery of such notice of exercise. If any Optional Shares are to be purchased, (a) each Underwriter agrees, severally and not jointly, to purchase the number of Optional Shares (subject to such adjustments to eliminate fractional shares as the Representative may determine) that bears the same proportion to the total number of Optional Shares to be purchased as the number of Firm Shares set forth on Schedule A opposite the name of such Underwriter bears to the total number of Firm Shares and (b) each of the Company and WEDGE agrees, severally and not jointly, to sell the number of Optional Shares (subject to such adjustments to eliminate fractional shares as the Representative may determine) that bears the same proportion to the total number of Optional Shares to be sold as the number of Optional Shares with respect to the Company or WEDGE, as applicable, set forth in the first paragraph of this Agreement bears to the total number of Optional Shares set forth therein. The Representative may cancel the option at any time prior to its expiration by giving written notice of such cancellation to the Company and WEDGE. Upon the written request of Chesapeake, the Underwriters agree to allocate a percentage (or such lesser amount as may be requested by Chesapeake) of the Optional Shares to be sold by the Company equal to the percentage of the outstanding Common Stock held by the

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Chesapeake (assuming the conversion of all outstanding convertible preferred stock or debt) on the First Closing Date (and, if applicable, at each Option Closing Date) (the " Chesapeake Optional Shares "), to the account of Chesapeake in accordance with Chesapeake's election to exercise the preemptive rights which it holds in connection with the Company's offering of those shares.

        (d)     Public Offering of the Offered Shares.     The Representative hereby advises the Company and the Selling Shareholders that the Underwriters intend to offer for sale to the public, initially on the terms set forth in the Prospectus, their respective portions of the Offered Shares as soon after this Agreement has been executed and the Registration Statement has been declared effective as the Representative, in its sole judgment, has determined is advisable and practicable.

        (e)     Payment for the Offered Shares.     Payment for the Offered Shares to be sold by the Company shall be made at the First Closing Date (and, if applicable, at each Option Closing Date) by wire transfer of immediately available funds to the order of the Company. Payment for the Offered Shares to be sold by each Selling Shareholder shall be made at the First Closing Date (and, if applicable, at each Option Closing Date) by wire transfer of immediately available funds to the order of such Selling Shareholder.

        It is understood that the Representative has been authorized, for its own account and the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price for, the Firm Shares and any Optional Shares the Underwriters have agreed to purchase. Jefferies, individually and not as the Representative of the Underwriters, may (but shall not be obligated to) make payment for any Offered Shares to be purchased by any Underwriter whose funds shall not have been received by the Representative by the First Closing Date or the applicable Option Closing Date, as the case may be, for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement.

        Each Selling Shareholder hereby agrees that it will pay all stock transfer taxes, stamp duties and other similar taxes, if any, payable upon the sale or delivery of the Offered Shares to be sold by such Selling Shareholder to the several Underwriters, or otherwise in connection with the performance of such Selling Shareholder's obligations hereunder.

        (f)     Delivery of the Offered Shares.     The Company and the Selling Shareholders, through the facilities of the Depository Trust Company (" DTC "), shall deliver, or cause to be delivered, to the Representative for the accounts of the several Underwriters a securities entitlement with respect to the Firm Shares to be sold by them at the First Closing Date, in each case against receipt of a wire transfer of immediately available funds for the amount of the purchase price therefor. The Company and WEDGE, through the facilities of DTC, shall also deliver, or cause to be delivered, to the Representative for the accounts of the several Underwriters, a securities entitlement with respect to the Optional Shares the Underwriters have agreed to purchase from them at the First Closing Date or the applicable Option Closing Date, as the case may be, in each case against the receipt of a wire transfer of immediately available funds for the amount of the purchase price therefor. At least two full business days prior to the First Closing Date (or the applicable Option Closing Date, as the case may be), (i) each Selling Shareholder shall deliver to the transfer agent and registrar of the Common Stock (the " Transfer Agent ") any certificates evidencing shares of Common Stock (to the extent that the Transfer Agent requires delivery of such certificates) necessary to cause the Transfer Agent to arrange for the delivery of the Offered Shares in accordance with the provisions of this Section 2(f) and authorize and instruct the Transfer Agent to cancel any such certificates and (ii) each of the Company and each Selling Shareholder shall authorize the Transfer Agent to arrange for the delivery of the Offered Shares in accordance with the provisions of this Section 2(f). The Offered Shares shall be registered in such names and denominations as the Representative shall have requested at least two full business days prior to the First Closing Date (or the applicable Option Closing Date, as the case may be). Upon delivery, the Offered Shares shall be registered in the name of Cede & Co., as nominee for DTC. Time

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shall be of the essence, and delivery at the time and place specified in this Agreement is a further condition to the obligations of the Underwriters.

        (g)     Delivery of Prospectus to the Underwriters.     Not later than 12:00 p.m. on the second business day following the date the Offered Shares are first released by the Underwriters for sale to the public, the Company shall deliver or cause to be delivered, copies of the Prospectus in such quantities and at such places as the Representative shall reasonably request.

        (h)     Repayment of Commissions.     

          (i)  If Chesapeake elects to purchase some or all of the Chesapeake Firm Shares in accordance with its election to exercise the preemptive rights which it holds in connection with the Company's offering of the Firm Shares, the Underwriters shall pay, as soon as is reasonably practicable after the First Closing Date, to the Company an amount equal to the number of Chesapeake Firm Shares purchased by Chesapeake in accordance with its election to exercise the preemptive rights which it holds in connection with the Company's offering of the Firm Shares, multiplied by the amount obtained by subtracting the purchase price per Firm Share to be paid by the several Underwriters to the Company set forth in Section 2(a) herein from the public offering price set forth on the outside front cover page of the Prospectus.

         (ii)  If Chesapeake elects to purchase some or all of the Chesapeake Optional Shares in accordance with its election to exercise the preemptive rights which it holds in connection with the Company's offering of the Optional Shares, the Underwriters shall pay, as soon as is reasonably practicable after the applicable First Closing Date or Option Closing Date, to the Company an amount equal to the number of Chesapeake Optional Shares purchased by Chesapeake in accordance with its election to exercise the preemptive rights which it holds in connection with the Company's offering of the Optional Shares, multiplied by the amount obtained by subtracting the purchase price per Optional Share to be paid by the several Underwriters to the Company set forth in Section 2(c) herein from the public offering price set forth on the outside front cover page of the Prospectus.

Section 3.    Additional Covenants .

        A.    Covenants of the Company.     The Company further covenants and agrees with each Underwriter as follows:

        (a)     Representative's Review of Proposed Amendments and Supplements.     During the period beginning on the date hereof and ending on the later of the First Closing Date or such date, as in the opinion of counsel for the Underwriters, the Prospectus is no longer required by law to be delivered in connection with sales by an Underwriter or dealer (the " Prospectus Delivery Period "), prior to amending or supplementing the Registration Statement (including any registration statement filed under Rule 462(b) under the Securities Act) or the Prospectus, the Company shall furnish to the Representative for review a copy of each such proposed amendment or supplement, and the Company shall not file any such proposed amendment or supplement without the Representative's consent (which shall not be unreasonably withheld or delayed).

        (b)     Securities Act Compliance.     After the date of this Agreement, the Company shall promptly advise the Representative in writing (i) of the receipt of any comments of, or requests for additional or supplemental information from, the Commission with respect to the Registration Statement or the Prospe