UNDERWRITING AGREEMENT

The undersigned, EV Energy Partners, L.P., a Delaware limited partnership (the “ Partnership ”), EV Energy GP, L.P., a Delaware limited partnership and general partner of the Partnership (the “ General Partner ”), EV Management, LLC, a Delaware limited liability company and general partner of the General Partner (“ GP LLC ”), EV Properties, L.P., a Delaware limited partnership (the “ Operating Partnership ”), EV Properties GP, LLC, a Delaware limited liability company and general partner of the Operating Partnership (the “ Operating Partnership GP ”), hereby confirm their agreement with the several Underwriters named in Schedule I hereto (the “ Underwriters ”), for whom Wachovia Capital Markets, LLC, Citigroup Global Markets Inc., Raymond James & Associates, Inc. and RBC Capital Markets Corporation are acting as representatives (the “ Representatives ”).

The Partnership, the General Partner, GP LLC, the Operating Partnership GP and the Operating Partnership are collectively referred to herein as the “ EVEP Parties .”  The Partnership, the General Partner, GP LLC, the Operating Partnership GP and the Operating Partnership and the other Subsidiaries (as defined in Section 4(r)) are referred to collectively herein as the “ Partnership Entities .”

1.            Description of Common Units .  The Partnership proposes to issue and sell to the Underwriters 3,500,000 common units (the “ Firm Units ”) representing limited partner interests in the Partnership (the “ Common Units ”).  The Partnership further proposes to grant to the Underwriters the right to purchase up to an additional 525,000 Common Units (the “ Option Units ”) under certain circumstances as provided in Section 3 of this Agreement.  The Firm Units and the Option Units are herein sometimes referred to as the “ Units ” and are more fully described in the Disclosure Package and the Final Prospectus (each hereinafter defined).

2.            Purchase, Sale and Delivery of the Firm Units .  On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Partnership agrees to sell to the Underwriters, and each such Underwriter agrees, severally and not jointly, (a) to purchase from the Partnership, at a purchase price of $19.54 per unit, the number of Firm Units set forth opposite the name of such Underwriter in Schedule I hereto and (b) to purchase from the Partnership any additional number of Option Units which such Underwriter may become obligated to purchase pursuant to Section 3 hereof.

Delivery of the Firm Units will be in book-entry form through the facilities of The Depository Trust Company, New York, New York (“ DTC ”). Delivery of the documents required by Section 6 hereof with respect to the Units shall be made available at or prior to 9:00 a.m. Central Time on June 16, 2009 at the offices of Haynes and Boone, LLP, 1221 McKinney, Suite 2100, Houston, Texas 77010 or at such other place as may be agreed upon between the Representatives and the Partnership (the “ Place of Closing ”), or at such other time and date not later than five full business days thereafter as the Representatives and the Partnership may agree, such time and date of payment and delivery being herein called the “ Initial Delivery Date .”  Time shall be of the essence, and delivery at the time and place specified pursuant to this Agreement is a further condition of the obligation of the Underwriters hereunder.

The Partnership will deliver the Firm Units to the Underwriters, against payment of the purchase price therefor in Federal (same day) Funds by wire transfer to an account at the bank specified by the Partnership.

The Partnership will cause its transfer agent to deposit the Firm Units pursuant to the Full Fast Delivery Program of the DTC.

It is understood that the Underwriters propose to offer the Units to the public upon the terms and conditions set forth in the Disclosure Package and the Final Prospectus.

3.            Purchase, Sale and Delivery of the Option Units .  The Partnership hereby grants the option to the Underwriters to purchase from the Partnership up to 525,000 Option Units, on the same terms and conditions as the Firm Units. No Option Units shall be sold or delivered unless the Firm Units previously have been, or simultaneously are, sold and delivered and such Option Units shall be sold at the same price as the Firm Units.

The option is exercisable by the Representatives at any time, in whole or in part, and from time to time, before the expiration of 30 days from the date of the Final Prospectus (or, if such 30th day shall be a Saturday or Sunday or a holiday, on the next day thereunder when the NASDAQ Global Select Market (the “ NASDAQ ”) is open for trading), for the purchase of all or part of the Option Units covered thereby, by notice given by the Representatives to the Partnership in the manner provided in Section 12 hereof, setting forth the number of Option Units as to which the Underwriters are exercising the option, and the date of delivery of said Option Units, which date shall not be more than five business days after such notice unless otherwise agreed to by the Partnership and the Representatives. The Underwriters may terminate the option at any time, as to any unexercised portion thereof, by giving written notice from the Representatives to the Partnership to such effect.  The percentage of Option Units to be purchased by each Underwriter shall be the same as the percentage of Firm Units purchased by such Underwriter.

The Underwriters shall make such allocation of the Option Units among them as may be required to eliminate purchases of fractional Units.

Delivery of Option Units will be in book-entry form through the facilities of DTC. Delivery of the documents required by Section 6 hereof with respect to the Option Units shall be made at the Place of Closing at or prior to 9:00 a.m. Central Time on the date designated in the notice given by the Representatives as provided above, or at such other time and date as the Representatives and the Partnership may agree (which may be the same as the Initial Delivery Date), such time and date of payment and delivery being herein called the “ Option Unit Delivery Date .”  The Initial Delivery Date and any Option Unit Delivery Date are sometimes each referred to as a “ Delivery Date .” Time shall be of the essence, and delivery at the time and place specified pursuant to this Agreement is a further condition of the obligation of the Underwriters hereunder.  On each Option Unit Delivery Date, the EVEP Parties shall provide the Underwriters such representations, warranties, agreements, opinions, letters, certificates and covenants with respect to Option Units as are required to be delivered on the Initial Delivery Date with respect to the Firm Units.

The Partnership will cause its transfer agent to deposit Option Units pursuant to the Full Fast Delivery Program of the DTC.

4.            Representations, Warranties and Agreements of the EVEP Parties .  The EVEP Parties jointly and severally represent and warrant to and agree with each Underwriter as set forth below:

(a)            Registration Statement/Prospectus . A registration statement (Registration No. 333-146428) on Form S-3 with respect to the Units, including a related Basic Prospectus (as defined below), has been prepared by the Partnership pursuant to and in conformity with the requirements of the Securities Act of 1933, as amended (the “ 1933 Act ”), and the rules and regulations thereunder (the “ 1933 Act Rules and Regulations ”) of the United States Securities and Exchange Commission (the “ Commission ”) and has been filed and declared effective by the Commission under the 1933 Act. The Partnership will file with the Commission a Final Prospectus (as defined below) in accordance with Rule 424(b). As filed, such Final Prospectus shall contain all information required by the 1933 Act and the 1933 Act Rules and Regulations, except to the extent the Underwriters shall agree in writing to a modification, shall be in all substantive respects in the form furnished to the Representatives prior to the Execution Time or, to the extent not completed at the Execution Time, shall contain only such specific additional information and other changes (beyond that contained in the Basic Prospectus and any Preliminary Prospectus) as the Partnership has advised the Representatives, prior to the Execution Time, will be included or made therein. Copies of such Registration Statement, including any amendments thereto, each related Preliminary Prospectus contained therein, and the exhibits, financial statements and schedules thereto have heretofore been delivered by the Partnership to the Underwriters. As used in this Agreement:

(i)           “ Basic Prospectus ” shall mean the prospectus referred to in paragraph 4(a) above contained in the Registration Statement at the Effective Date.

(ii)          “ Disclosure Package ” shall mean, as of the Execution Time, the most recent Preliminary Prospectus, together with (A) any Issuer Free Writing Prospectus filed by the Partnership on or before the Execution Time and identified on Schedule II hereto, and (B) the pricing information identified on Schedule II hereto.

(iii)         “ Effective Date ” shall mean any date as of which any part of the Registration Statement became, or is deemed to have become, effective under the 1933 Act in accordance with the 1933 Act Rules and Regulations.

(iv)         “ Execution Time ” shall mean the date and time (7:30 a.m. Central Time) that this Agreement is executed and delivered by the parties hereto.

(v)          “ Final Prospectus ” shall mean the prospectus supplement relating to the Units that was first filed pursuant to Rule 424(b) after the Execution Time, together with the Basic Prospectus.

(vi)         “ Issuer Free Writing Prospectus ” means each “free writing prospectus” (as defined in Rule 405 of the 1933 Act Rules and Regulations) prepared by or on behalf of the Partnership or used or referred to by the Partnership in connection with the offering of the Units.

(vii)        “ Preliminary Prospectus ” shall mean any preliminary prospectus supplement to the Basic Prospectus which describes the Units and the offering thereof and is used prior to filing of the Final Prospectus, together with the Basic Prospectus.

(viii)       “ Registration Statement ” shall mean the registration statement referred to in paragraph 4(a) above, including exhibits and financial statements and any prospectus supplement relating to the Units that is filed with the Commission pursuant to Rule 424(b) and deemed part of such registration statement pursuant to Rule 430A, as amended at the Execution Time and, in the event any post-effective amendment thereto or any Rule 462(b) Registration Statement becomes effective prior to the Initial Delivery Date, shall also mean such registration statement as so amended or such Rule 462(b) Registration Statement, as the case may be.

(ix)          “ Rule 462(b) Registration Statement ” shall mean a registration statement and any amendments thereto filed pursuant to Rule 462(b) relating to the offering covered by the registration statement referred to in Section 4(a) hereof.

Any reference to any Preliminary Prospectus, the Disclosure Package or the Basic Prospectus shall be deemed to refer to and include any documents incorporated by reference therein pursuant to Form S-3 under the 1933 Act as of the date of such Preliminary Prospectus or the Basic Prospectus, as the case may be, or in the case of the Disclosure Package, as of the Execution Time. Any reference to the “most recent Preliminary Prospectus” shall be deemed to refer to the latest Preliminary Prospectus included in the Registration Statement or filed pursuant to Rule 424(b) on or prior to the date hereof. Any reference to any amendment or supplement to any Preliminary Prospectus or the Basic Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended (the “ 1934 Act ”), after the date of such Preliminary Prospectus or the Basic Prospectus, as the case may be, and incorporated by reference in such Preliminary Prospectus or the Basic Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include the most recent annual report of the Partnership on Form 10-K filed with the Commission pursuant to Section 13(a) or 15(d) of the 1934 Act after the Effective Date that is incorporated by reference in the Registration Statement. The Commission has not issued any order preventing or suspending the use of any Preliminary Prospectus or the Basic Prospectus or suspending the effectiveness of the Registration Statement, and no proceeding or examination for such purpose has been instituted or, to the Partnership’s knowledge, threatened by the Commission. The Commission has not notified the Partnership of any objection to the use of the form of the Registration Statement.

(b)            Form of Documents . The Registration Statement complied and will comply in all material respects on each Effective Date and on the applicable Delivery Date, and any amendment to the Registration Statement filed after the date hereof will comply in all material respects when filed, to the requirements of the 1933 Act and the 1933 Act Rules and Regulations. The most recent Preliminary Prospectus complied, and the Final Prospectus will comply, in all material respects when filed with the Commission pursuant to Rule 424(b) to the requirements of the 1933 Act and the 1933 Act Rules and Regulations.

(c)            No Material Misstatements or Omissions in the Registration Statement . The Registration Statement did not, as of each Effective Date, contain an 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; provided , however, that the Partnership makes no representations or warranties as to the information contained in or omitted from the Registration Statement in reliance upon and in conformity with written information furnished to the Partnership by or on behalf of the Underwriters specifically for inclusion in the Registration Statement, it being understood and agreed that the only such information furnished by the Underwriters consists of the information described as such in Section 13 hereof.

(d)            No Material Misstatements or Omissions in the Final Prospectus . The Final Prospectus will not, as of its date and on the applicable Delivery Date, contain an 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; provided , however, that the Partnership makes no representations or warranties as to the information contained in or omitted from the Final Prospectus in reliance upon and in conformity with written information furnished to the Partnership by or on behalf of the Underwriters specifically for inclusion in the Final Prospectus, it being understood and agreed that the only such information furnished by the Underwriters consists of the information described as such in Section 13 hereof.

(e)            No Material Misstatements or Omissions in the Disclosure Package . The Disclosure Package did not, as of the Execution Time, contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided , however, that the Partnership makes no representations or warranties as to the information contained in or omitted from the Disclosure Package in reliance upon and in conformity with written information furnished to the Partnership by or on behalf of the Underwriters specifically for inclusion in the Disclosure Package, it being understood and agreed that the only such information furnished by the Underwriters consists of the information described as such in Section 13 hereof.

(f)             Ineligible Issuer . (i) At the time of the initial filing of the Registration Statement and (ii) as of the Execution Time (with such date being used as the determination date for purposes of this clause (ii)), the Partnership was not and is not an Ineligible Issuer (as defined in Rule 405), without taking account of any determination by the Commission pursuant to Rule 405 that it is not necessary that the Partnership be considered an Ineligible Issuer.

(g)            Issuer Free Writing Prospectus . Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433), when considered together with the Disclosure Package as of the Execution Time, did not contain an 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. Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433) does not include any information that conflicts with the information contained in the Disclosure Package, including any document incorporated by reference therein that has not been superseded or modified. The foregoing sentence does not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Partnership by or on behalf of the Underwriters specifically for inclusion in the Registration Statement or the Prospectus (or any supplement thereto), it being understood and agreed that the only such information furnished by the Underwriters consists of the information described as such in Section 13 hereof.

(h)            Other Sales . The Partnership has not sold or issued any Common Units during the six-month period preceding the date of the Initial Delivery Date, other than pursuant to acquisitions, employee benefit plans, qualified options plans or other employee compensation plans or pursuant to outstanding options, rights or warrants described in the Disclosure Package and the Final Prospectus.

(i)            Formation and Due Qualification .   Formation and Due Qualification .  Each of the Partnership Entities has been duly formed or incorporated and is validly existing as a limited partnership or limited liability company, as the case may be, in good standing under the laws of its respective jurisdiction of formation or incorporation with all necessary power and authority to own or lease its properties and to conduct its business, in all material respects as described in the Disclosure Package and the Final Prospectus (and any amendments or supplement thereto).  Each of the Partnership Entities is, and at each Delivery Date will be, duly registered or qualified to do business and is in good standing as a foreign limited partnership or foreign limited liability company, as the case may be, in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such registration or qualification, except where the failure so to register or qualify would not (i) have a material adverse effect on the position (financial or other), partners’ or members’ equity, results of operations, business or prospects of the Partnership Entities taken as a whole (a “ Material Adverse Effect ”) or (ii) subject the limited partners of the Partnership to any material liability or disability, as set forth under its name on Schedule III to this Agreement.

(j)            Ownership of the General Partner Interest in the Partnership .  The General Partner is the sole general partner of the Partnership with a 2% general partner interest in the Partnership.  Such general partner interest has been duly authorized and validly issued in accordance with the First Amended and Restated Agreement of Limited Partnership of the Partnership (as amended, the “ Partnership Agreement ”) and are fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-303 and 17-607 of the Delaware Revised Uniform Limited Partnership Act (the “ Delaware LP Act ”)), and the General Partner owns such general partner interest free and clear of all liens, encumbrances (except restrictions on transferability described in the Prospectus), security interests, equities, charges or claims.

(k)            Capitalization .  At each Delivery Date (assuming that the Underwriters do not purchase the Option Units), after giving effect to the issuance of the Firm Units, the issued and outstanding limited partner interests of the Partnership will consist of 16,630,471 Common Units, 3,100,000 subordinated units (as defined in the Partnership Agreement, the “ Subordinated Units ”) and the incentive distribution rights (as defined in the Partnership Agreement (the “ Incentive Distribution Rights ”). All outstanding Common Units, Subordinated Units and the Incentive Distribution Rights and the limited partner interests represented thereby have been duly authorized and validly issued in accordance with the Partnership Agreement and are fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by matters described in Sections 17-607 and 17-804 of the Delaware LP Act).

(l)             Ownership of Lock-Up Units and the Incentive Distribution Rights.   (i) EnerVest, Ltd., a Texas limited partnership (together with its direct and indirect wholly-owned subsidiaries “ EnerVest ”), owns 67,923 Common Units and 1,611,596 Subordinated Units, (ii) EV Investors, L.P., a Delaware limited partnership (“ EV Investors ”), owns 155,000 Subordinated Units, (iii) EnCap Energy Capital Fund V, L.P., a Texas limited partnership, and EnCap V-B Acquisitions, L.P., a Texas limited partnership (collectively, the “ Encap Entities ”), own 25,571 Common Units and 436,170 Subordinated Units (all such Common Units and Subordinated Units being collectively referred to herein as the “ Lock-Up Units ”) as described in the Disclosure Package and the Final Prospectus and (v) the General Partner owns all of the Incentive Distribution Rights; all of such Lock-Up Units and Incentive Distribution Rights and the limited partner interests represented thereby have been duly authorized and validly issued in accordance with the Partnership Agreement, and are fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Sections 17-303 and 17-607 of the Delaware LP Act); and each of EnerVest, EV Investors and the EnCap Entities owns their respective Lock-Up Units, and the General Partner owns the Incentive Distribution Rights, free and clear of all liens, encumbrances (except restrictions on transferability as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges or claims.

(m)            Valid Issuance of the Units.   At the Initial Delivery Date or the Option Unit Delivery Date, as the case may be, the Firm Units or the Option Units, as the case may be, and the limited partner interests represented thereby, will be duly authorized in accordance with the Partnership Agreement and, when issued and delivered to the Underwriters against payment therefor in accordance with the terms hereof, will be validly issued, fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Sections 17-303 and 17-607 of the Delaware LP Act).

(n)            Ownership of Membership Interests in the General Partner .  GP LLC owns 100% of the outstanding general partner interests in the General Partner and EnerVest, the Encap Entities and EV Investors own 100% of the outstanding limited partner interests in the General Partner; all of such interests have been duly authorized and validly issued in accordance with the First Amended and Restated Agreement of Limited Partnership of the General Partner (the “ General Partner Partnership Agreement ”) and are fully paid (to the extent required under the General Partner LP Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-303 and 17-607 of the Delaware LP Act), and GP LLC, EnerVest, the EnCap Entities and EV Investors own such interests free and clear of all liens, encumbrances (except as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges or claims.

(o)            Ownership of Limited Liability Company Interests in the GP LLC .  EnerVest owns 100% of the outstanding limited liability company interests in GP LLC; all of such interests have been duly authorized and validly issued in accordance with the Amended and Restated Limited Liability Company Agreement of the GP LLC (the “ GP LLC LLC Agreement ”) and are fully paid (to the extent required under the GP LLC LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware Limited Liability Company Act (the “ Delaware LLC Act ”)), and EnerVest owns such interests free and clear of all liens, encumbrances (except as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges or claims.

(p)            Ownership of Partnership Interests in the Operating Partnership .  Operating Partnership GP owns 100% of the outstanding general partner interests in the Operating Partnership and the Partnership owns 100% of the outstanding limited partner interests in the Operating Partnership; all of such interests have been duly authorized and validly issued in accordance with the Second Amended and Restated Agreement of Limited Partnership of the Operating Partnership (the “ Operating Partnership LP Agreement ”) and are fully paid (to the extent required under the Operating Partnership LP Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-303 and 17-607 of the Delaware LP Act), and Operating Partnership GP and the Partnership owns such interests free and clear of all liens, encumbrances (except as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges or claims.

(q)            Ownership of Limited Liability Company Interests in the Operating Partnership GP .  The Partnership owns 100% of the outstanding limited liability company interests in Operating Partnership GP; all of such interests have been duly authorized and validly issued in accordance with the Amended and Restated Limited Liability Company Agreement of the Operating Partnership GP (the “ Operating Partnership GP LLC Agreement ”), and are fully paid (to the extent required under the Operating Partnership GP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act), and the Partnership owns such interests free and clear of all liens, encumbrances (except as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges or claims.

(r)            Ownership of the Subsidiaries . The Partnership owns, directly or indirectly, 100% of the limited liability company interests, partnership interests or capital stock, as the case may be, in EVPP GP LLC, a Delaware limited liability company (“ EVPP GP ”), EVCG GP LLC, a Delaware limited liability company (“ EVCG GP ”), EnerVest Production Partners, Ltd., a Texas limited partnership (“ EVPP ”), EnerVest Monroe Gathering, Ltd., a Texas limited partnership (“ Gathering ”), EnerVest Monroe Marketing, Ltd., a Texas limited partnership (“ Marketing ”), CGAS Properties, L.P., a Delaware limited partnership (“ Clinton Properties ”), EnerVest Cargas, Ltd., a Texas limited partnership (“ EV Cargas ”), Lower Cargas Operating Company, LLC, a Louisiana limited liability company (“ LCOC ”), and EV Energy Finance Corp., a Delaware corporation (“ Finance ”) (collectively, the “ Subsidiaries ,” and together with the Operating Partnership and the Operating Partnership GP, the “ Operating Subsidiaries ”) free and clear of all liens, encumbrances (except as described in the Disclosure Package and the Final Prospectus), security interests, equities, charges and other claims. Such limited liability company interests, partnership interests or capital stock, as the case may be, have been duly authorized and validly issued in accordance with the limited liability company,  limited partnership agreements or charter documents, as the case may be, of the respective Subsidiaries, and are fully paid (to the extent required under their respective limited liability company agreement or limited partnership agreement) and non-assessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act, in the case of a Delaware limited liability company; Sections 17-303 and 17-607 of the Delaware LP Act, in the case of a Delaware limited partnership; Section 153.210 of the Texas Business Organizations Code, in the case of a Texas limited partnership; and Section 1328 of the Louisiana Limited Liability Act, in the case of a Louisiana limited liability company).

(s)            No Other Subsidiaries.   Other than ownership interests in the Operating Subsidiaries, the Partnership 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 Partnership’s Annual Report on Form 10-K for the most recent fiscal year. Neither the Partnership nor any of its subsidiaries own, directly or indirectly, any equity or long-term debt securities of any corporation, partnership, limited liability company, joint venture, association or other entity, other than as set forth in Exhibit 21.1 to the Partnership’s Annual Report on Form 10-K for the most recent fiscal year. Other than its ownership of its general partner interests in the Partnership, the General Partner does not own, and as of each Delivery Date will not own, directly or indirectly, any equity or long-term debt securities of any corporation, partnership, limited liability company, joint venture, association or other entity.  Other than its ownership of its general partner interests in the General Partner, GP LLC does not own, and as of each Delivery Date will not own, directly or indirectly, any equity or long-term debt securities of any corporation, partnership, limited liability company, joint venture, association or other entity.

(t)            No Preemptive Rights, Registration Rights or Options.   Except as described in the Disclosure Package and the Final Prospectus, there are no options, warrants, preemptive rights or other rights to subscribe for or to purchase, nor any restriction upon the voting or transfer of, any partnership or limited liability company interests in any Partnership Entity, in each case pursuant to the partnership agreement or limited liability company agreement of such Partnership Entity (collectively, the “ Organizational Agreements ”) or the certificate of limited partnership or formation or incorporation, bylaws or other organizational documents of such Partnership Entity (collectively together with the Organizational Agreements, the “ Organizational Documents ”) or any other agreement or instrument to which such Partnership Entity is a party or by which it is bound.  Except for any such rights as have been effectively waived, neither the filing of the Registration Statement, the Preliminary Prospectus or the Final Prospectus nor the offering or sale of the Units as contemplated by this Agreement gives rise to any rights for or relating to the registration of any Common Units or other securities of any of the Partnership Entities.  Except as described in the Disclosure Package and the Final Prospectus and for options granted pursuant to employee benefit plans, qualified unit option plans, or other employee compensation plans in effect as of the Execution Time, there are no outstanding options or warrants to purchase any capital stock or partnership or membership interests of any of the Partnership Entities.

(u)            Authority and Authorization.   The Partnership has all requisite power and authority to issue, sell and deliver the Units, in accordance with and upon the terms and conditions set forth in this Agreement, the Partnership Agreement, the Registration Statement, the Disclosure Package and the Final Prospectus. At each Delivery Date, all corporate, partnership and limited liability company action, as the case may be, required to be taken by the Partnership Entities or any of their stockholders, members or partners for the authorization, issuance, sale and delivery of the Units shall have been validly taken.

(v)            Authorization of Underwriting Agreement.   This Agreement has been duly authorized and validly executed and delivered by each of the EVEP Parties.

(w)            Enforceability of Other Agreements.   Each of the Organizational Agreements has been duly authorized, executed and delivered by the parties thereto and is a valid and legally binding agreement of such party, enforceable against such party in accordance with its terms; provided that, the enforceability thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and by general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law); and provided , further, that the indemnity, contribution and exoneration provisions contained in any of such agreements may be limited by applicable laws and public policy.

(x)            No Conflicts .  None of the offering, issuance and sale by the Partnership of the Units, the execution, delivery and performance of this Agreement by the EVEP Parties or the consummation of the transactions contemplated hereby (i) conflicts or will conflict with or constitutes or will constitute a violation of the Organizational Documents, (ii) conflicts or will conflict with or constitutes or will constitute a breach or violation of, or a default (or an event which, with notice or lapse of time or both, would constitute such a default) under any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which any of the Partnership Entities is a party or by which any of them or any of their respective properties may be bound, (iii) violates or will violate any statute, law or regulation or any order, judgment, decree or injunction of any court or governmental agency or body directed to any of the Partnership Entities or any of their properties in a proceeding to which any of them or their property is a party or (iv) results or will result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of any of the Partnership Entities, which conflicts, breaches, violations, defaults or liens, in the case of clauses (ii), (iii) or (iv), would, individually or in the aggregate, have a Material Adverse Effect or could materially impair the ability of any of the Partnership Entities to perform their obligations under this Agreement.

(y)            No Consents . No permit, consent, approval, authorization, order, registration, filing or qualification (“ Consent ”) of or with any court, governmental agency or body having jurisdiction over any of the Partnership Entities or any of their respective properties is required in connection with the offering, issuance and sale by the Partnership of the Units, the execution, delivery and performance of this Agreement by the EVEP Parties, or the consummation by the Partnership Entities of the transactions contemplated hereby, except for such consents, approvals, authorizations, orders and registrations or qualifications as may be required under the 1933 Act, the 1933 Act Rules and Regulations, the 1934 Act and the rules and regulations thereunder (the “ 1934 Act Rules and Regulations ”) and state securities or “Blue Sky” laws and applicable rules and regulations under such laws.

(z)            No Default .  None of the Partnership Entities is (i) in violation of its Organizational Documents (ii) in violation of any law, statute, ordinance, administrative or governmental rule or regulation applicable to it or of any order, judgment, decree or injunction of any court or governmental agency or body having jurisdiction over it or (iii) in breach, default (or an event which, with notice or lapse of time or both, would constitute such a default) or violation in the performance of any obligation, agreement or condition contained in any bond, debenture, note or any other evidence of indebtedness or in any agreement, indenture, lease or other instrument to which it is a party or by which it or any of its properties may be bound, which breach, default or violation in the case of clause (ii) or (iii) would, if continued, have a Material Adverse Effect or could materially impair the ability of any of the Partnership Entities to perform their obligations under this Agreement.  To the knowledge of the EVEP Parties, no third party to any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which any of the Partnership Entities is a party or by which any of them is bound or to which any of their properties is subject, is in breach, default or violation of any such agreement, which breach, default or violation would, if continued, have a Material Adverse Effect or could materially impair the ability of any of the Partnership Entities to perform their obligations under this Agreement.

(aa)          Conformity of Securities to Descriptions in the Disclosure Package and the Final Prospectus .  The Units, when issued and delivered in accordance with the terms of the Partnership Agreement against payment therefor as provided herein will conform in all material respects to the description thereof contained in the Disclosure Package and the Final Prospectus.

(bb)         Independent Public Accountants.   The accountants, Deloitte & Touche LLP, who have certified the audited financial statements contained or incorporated by reference in the Registration Statement and the most recent Preliminary Prospectus (or any amendment or supplement thereto), are an independent registered public accountants with respect to the Partnership and the General Partner as required by the 1933 Act and the 1933 Act Rules and Regulations and the rules and regulations of the Public Company Accounting Oversight Board (the “ PCAOB ”).

(cc)          Financial Statements.   As of March 31, 2009, the Partnership would have had, on the consolidated, as adjusted basis indicated in the Disclosure Package and the Final Prospectus, a capitalization as set forth therein. The historical financial statements (including the related notes and supporting schedules) contained or incorporated by reference in the Registration Statement, the Disclosure Package and the Final Prospectus, together with the related notes (and any amendment or supplement thereto) comply as to form in all material respects with the requirements of Regulation S-X under the 1933 Act and present fairly in all material respects the financial position, results of operations and cash flows of the entities purported to be shown thereby on the basis stated therein at the respective dates or for the respective periods to which they apply and have been prepared in accordance with generally accepted accounting principles consistently applied throughout the periods involved, except to the extent disclosed therein.  The selected financial information set forth in the Registration Statement, the Disclosure Package and the Final Prospectus (and any amendment or supplement thereto) is accurately presented in all material respects and prepared on a basis consistent with the audited and unaudited historical consolidated financial statements and pro forma financial statements, as applicable, from which it has been derived. There are no financial statements (historical or pro forma) that are required to be contained or incorporated by reference in the Registration Statement, the Prospectus and the Disclosure Package that are not contained or incorporated by reference as required.

(dd)         Independent Petroleum Engineers .  Cawley, Gillespie & Associates, Inc.  Services, whose reports dated December 31, 2008, 2007 and 2006 are referenced in the Registration Statement, Disclosure Package and the Final Prospectus and who has delivered the letter referred to in Section 6(g) hereof, was, as of the date of each such report, and is, as of the date hereof, an independent reserve engineer with respect to the Partnership.

(ee)          Title to Real Property .  The Partnership Entities have good, valid and indefeasible title to all of the interests in oil and gas properties underlying the Partnership Entities estimates of their net proved reserves contained in the Registration Statement, the Disclosure Package and the Final Prospectus and to all other real and personal property reflected in the Registration Statement, the Disclosure Package and the Final Prospectus as assets owned by them, in each case, free and clear of all (i) liens and security interests or (ii) other claims and other encumbrances (other than liens or security interests) except, in each case, (1) as described, and subject to the limitations contained, in the Registration Statement, the Disclosure Package and the Final Prospectus or (2) such as do not materially interfere with the use of such properties taken as a whole as they have been used in the past and are proposed to be used in the future as described, and subject to limitations contained, in the Registration Statement, the Disclosure Package and the Final Prospectus; provided that, with respect to any real property and buildings held under lease by any Partnership Entity, such real property and buildings are held under valid and subsisting and enforceable leases with such exceptions as do not materially interfere with the use of the properties of the Partnership Entities taken as a whole as they have been used in the past as described, subject to the limitations contained, in the Registration Statement, the Disclosure Package and the Final Prospectus and are proposed to be used in the future as described in contained in the Registration Statement, the Disclosure Package and the Final Prospectus; the leases, mineral interests, operating agreements and other contract rights to which the Partnership Entities are a party give the Partnership Entities the right, in all material respects, to explore, develop or produce hydrocarbons as described, and subject to the limitations contained, in the Registration Statement, the Disclosure Package and the Final Prospectus.  The care taken by the Partnership Entities in acquiring or otherwise procuring such leases or mineral interests was generally consistent with standard industry practices in the areas in which the Partnership Entities operate for acquiring or procuring leases and interests therein to explore, develop or produce hydrocarbons.

(ff)           Information Underlying Reserve Report .  The information underlying the estimates of reserves of the Partnership Entities, which was supplied by the Partnership Entities to Cawley, Gillespie & Associates, Inc., for purposes of preparing the reserve reports, the estimates of net proved reserves and pre-tax present value, discounted at 10%, attributable thereto, and the letters (the “ Reserve Report Letters ”) of Cawley, Gillespie & Associates, Inc., including, without limitation, production volumes, costs of operation and development, current prices for production, agreements relating to current and future operations and sales of production, was true and correct in all material respects on the dates such estimates were made and such information was supplied and was prepared in accordance with customary industry practices; other than normal production of the reserves and intervening market commodity price fluctuations, the Partnership Entities are not aware of any facts or circumstances that would result in a material adverse change in the reserves, or the present value of future net cash flows therefrom, as described in the Registration Statement, Disclosure Package and the Final Prospectus and as reflected in the Reserve Report Letters; estimates of such reserves and present values as described in the Registration Statement, Disclosure Package and the Final Prospectus and reflected in the Reserve Report Letters comply in all material respects with the applicable requirements of Regulation S-X and Industry Guide 2 under the 1933 Act.

(gg)         No Material Adverse Change. None of the Partnership Entities has sustained, since the date of the latest audited financial statements contained or incorporated by reference  in the Registration Statement, the Disclosure Package and the Final Prospectus, any material 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, investigation, order or decree, otherwise than as set forth or contemplated in the Registration Statement, the Disclosure Package and the Final Prospectus (or any amendment or supplement thereto). Except as disclosed in the Registration Statement, the Prospectus and the Disclosure Package, subsequent to the respective dates as of which such information is given in the Registration Statement, the Disclosure Package and the Final Prospectus (or any amendment or supplement thereto), (i) none of the Partnership Entities has incurred any liability or obligation, indirect, direct or contingent, or entered into any transactions, not in the ordinary course of business, that, singly or in the aggregate, is material to the Partnership Entities, (ii) there has not been any material change in the capitalization, or material increase in the short-term debt or long-term debt, of any Partnership Entity and (iii) there has not been any material adverse change, or any development involving or which may reasonably be expected to involve, singly or in the aggregate, a prospective material adverse change in or affecting the general affairs, business, prospects, properties, management, condition (financial or other), partners’ equity, members’ equity, net worth or results of operations of the Partnership Entities.

(hh)         Legal Proceedings or Contracts to be Described or Filed.   There are no legal or governmental proceedings pending or, to the knowledge of the EVEP Parties, threatened, against any of the Partnership Entities, or to which any of the Partnership Entities is a party, or to which any of their respective properties is subject, that are required to be described in the Registration Statement, the Disclosure Package and the Final Prospectus (or any amendment or supplement thereto) but are not described as required, and there are no agreements, contracts, indentures, leases or other instruments that are required to be described in the Registration Statement, the Disclosure P