UNDERWRITING AGREEMENT

Exhibit 1.1

Execution Copy

10,000,000

Common Units

REGENCY ENERGY PARTNERS LP

UNDERWRITING AGREEMENT

July 26, 2007

UNDERWRITING AGREEMENT

July 26, 2007

UBS Securities LLC
Goldman, Sachs & Co.
Morgan Stanley & Co. Incorporated
     as Representatives of the several Underwriters

A.G. Edwards & Sons, Inc.
Credit Suisse Securities (USA) LLC
J.P. Morgan Securities Inc.
Wachovia Capital Markets, LLC
     As Managing Underwriters

c/o UBS Securities LLC
299 Park Avenue
New York, New York 10171-0026

Ladies and Gentlemen:

          Regency Energy Partners LP, a Delaware limited partnership (the “ Partnership ”), proposes to issue and sell to the underwriters named in Schedule A annexed hereto (the “ Underwriters ”), for whom UBS Securities LLC (“ UBS ”), Goldman, Sachs & Co. and Morgan Stanley & Co. Incorporated are acting as representatives (collectively, the “ Representatives ”), an aggregate of 10,000,000 common units (the “ Firm Units ”) representing limited partner interests in the Partnership (the “ Common Units ”). In addition, the Partnership proposes to grant to the Underwriters the option to purchase from the Partnership up to an additional 1,500,000 Common Units (the “ Additional Units ”). The Firm Units and the Additional Units are hereinafter collectively sometimes referred to as the “ Units .” The Units are described in the Prospectus, which is defined below.

          Regency GP LP, a Delaware limited partnership (the “ General Partner ”), serves as the general partner of the Partnership and Regency GP LLC, a Delaware limited liability company (“ GP LLC ”), serves as the general partner of the General Partner. At the time of purchase, the Partnership will be the sole owner of Regency Gas Services LP, a Delaware limited partnership (the “ Operating Partnership ”), and the sole member of Regency OLP GP LLC, a Delaware limited liability company (the “ Operating Partnership GP ”), which serves as the general partner of Regency Gas Services LP. Regency GP Acquirer LP (the “ GP Acquirer ”), a Delaware limited partnership and a wholly-owned subsidiary of GE Energy Financial Services, Inc. (“ GE EFS ”), an indirect subsidiary of GE Electric Company (collectively with their affiliates, the “ GE Investors ”), is the sole owner of all of the membership interests in GP LLC. Each of Regency Waha LP, LLC, a Delaware limited liability company, Regency Intrastate Gas LLC, a Delaware limited liability company, Regency Midcon Gas LLC, a Delaware limited liability company, Regency Liquids Pipeline LLC, a Delaware limited liability company, Regency Gas Gathering and Processing LLC, a Delaware limited liability company, Gulf States Transmission Corporation, a Louisiana corporation, Regency Waha GP, LLC, a Delaware

limited liability company, Regency NGL GP, LLC, a Delaware limited liability company, Regency Gas Marketing GP, LLC, a Delaware limited liability company, Regency NGL Marketing LP, a Delaware limited partnership, Regency Gas Marketing LP, a Delaware limited partnership, Regency Gas Services Waha, LP, a Delaware limited partnership, Regency TS GP LLC, a Delaware limited liability company, Regency FS GP LLC, a Delaware limited liability company, Regency GU GP LLC, a Delaware limited liability company, Regency Guarantor GP LLC, a Delaware limited liability company, Regency Operating GP LLC, a Delaware limited liability company, Regency TS Acquisition GP LLC, a Delaware limited liability company, Regency FN GP LLC, a Delaware limited liability company, Regency TGG LLC, a Texas limited liability company, Regency TS Acquisition LP, a Delaware limited partnership, Regency Eastex Protreat I LP, a Delaware limited partnership, Regency Eastex Protreat II LP, a Delaware limited partnership, Regency Field Services LP, a Delaware limited partnership, Regency Frio Newline LP, a Delaware limited partnership , Regency Gas Utility LP, a Delaware limited partnership, Regency Guarantor LP, a Delaware limited partnership, Regency Operating LP, a Delaware limited partnership, Regency Eastex Newline LP, a Delaware limited partnership, Regency FS LP, a Delaware limited partnership, Regency Gas Company Ltd., a Texas limited partnership, Regency Pipeline Company Inc., a Texas corporation, Palafox Joint Venture, a Texas joint venture, Pueblo Holdings, Inc., a Delaware corporation, Regency Oil Pipeline LLC, a Delaware limited liability company, Pueblo Midstream Gas Corporation, a Texas corporation, and Pueblo Energy Marketing Inc., a Texas corporation is sometimes referred to herein individually as a “ Subsidiary ” and collectively as the “ Subsidiaries .”

          The Partnership, the General Partner, GP LLC, the Operating Partnership and the Operating Partnership GP are sometimes referred to herein collectively as the “ Regency Parties .” The Partnership, the General Partner, GP LLC, the Operating Partnership, the Operating Partnership GP and the Subsidiaries are sometimes referred to herein collectively as the “ Partnership Entities .”

          The Partnership has prepared and filed, in accordance with the provisions of the Securities Act of 1933, as amended, and the rules and regulations thereunder (collectively, the “ Act ”), with the Securities and Exchange Commission (the “ Commission ”) a registration statement on Form S-3 (File No. 333-141809) under the Act (the “ registration statement ”), including a prospectus, which registration statement incorporates by reference documents which the Partnership has filed, or will file, in accordance with the provisions of the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder (collectively, the “ Exchange Act ”). Amendments to such registration statement, if necessary or appropriate, have been similarly prepared and filed with the Commission in accordance with the Act. Such registration statement, as so amended, has become effective under the Act.

          Except where the context otherwise requires, “ Registration Statement ,” as used herein, means the registration statement, as amended at the time of such registration statement’s effectiveness for purposes of Section 11 of the Act, as such section applies to the respective Underwriters (the “ Effective Time ”), including (i) all documents filed as a part thereof or incorporated or deemed to be incorporated by reference therein, (ii) any information contained or incorporated by reference in a prospectus filed with the Commission pursuant to Rule 424(b) under the Act, to the extent such information is deemed, pursuant to Rule 430B or Rule 430C under the Act, to be part of the registration statement at the Effective Time, and (iii) any registration statement filed to register the offer and sale of Units pursuant to Rule 462(b) under the Act.

     2.  Payment and Delivery . Payment of the purchase price for the Firm Units shall be made to the Partnership by Federal Funds wire transfer, against electronic delivery of the certificates for the Firm Units in book entry form to you through the facilities of The Depository Trust Company (“ DTC ”) for the respective accounts of the Underwriters. Such payment and delivery shall be made at 9:00 A.M., Houston, Texas time, on July 31, 2007 (unless another time shall be agreed to by you and the Partnership or unless postponed in accordance with the provisions of Section 8 hereof). The time at which such payment and delivery are to be made is hereinafter sometimes called “ the time of purchase .” Electronic transfer of the Firm Units shall be made to you at the time of purchase in such names and in such denominations as you shall specify.

          Payment of the purchase price for the Additional Units shall be made at the additional time of purchase in the same manner and at the same office as the payment for the Firm Units. If the additional time of purchase occurs after August 7, 2007, the purchase price for each Additional Unit shall be reduced by the amount of the quarterly distribution per Common Unit paid by the Partnership to holders of record as of August 7, 2007 for the quarter ended June 30, 2007. Electronic transfer of the Additional Units shall be made to you at the additional time of purchase in such names and in such denominations as you shall specify.

          Deliveries of the documents described in Section 6 hereof with respect to the purchase of the Units shall be made at the offices of Vinson & Elkins L.L.P., First City Tower, 1001 Fannin, Suite 2500, Houston, Texas 77002, at 9:00 A.M., Houston, Texas time, on the date of the closing of the purchase of the Firm Units or the Additional Units, as the case may be.

     3.  Representations and Warranties of the Regency Parties . Each of the Regency Parties party hereto, jointly and severally, represents and warrants to and agrees with each of the Underwriters that:

     (a) Effectiveness of Registration Statement . The Registration Statement has heretofore become effective under the Act or, with respect to any registration statement to be filed to register the offer and sale of Units pursuant to Rule 462(b) under the Act, will be filed with the Commission and become effective under the Act no later than 10:00 P.M., New York City time, on the date of determination of the public offering price for the Units; no stop order of the Commission preventing or suspending the use of any Basic Prospectus, the Pre-Pricing Prospectus, the Prospectus Supplement, the Prospectus or any Permitted Free Writing Prospectus or the effectiveness of the Registration Statement has been issued, and no proceedings for such purpose have been instituted or, to the Partnership’s knowledge, are threatened by the Commission; the Exchange Act Registration Statement has become effective as provided in Section 12 of the Exchange Act.

     (b) Registration Statement . The Registration Statement complied when it became effective, complies as of the date hereof and, as amended or supplemented, at the time of purchase, each additional time of purchase, if any, and at all times during which a

prospectus is required by the Act to be delivered (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with any sale of Units, will comply, in all material respects, with the requirements of the Act; the conditions to the use of Form S-3 in connection with the offering and sale of the Units as contemplated hereby have been satisfied; the Registration Statement meets, and the offering and sale of the Units as contemplated hereby complies with, the requirements under Rule 415 under the Act; the Registration Statement did not, as of the Effective Time, 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; each Pre-Pricing Prospectus complied, at the time it was filed with the Commission, and complies as of the date hereof, in all material respects with the requirements of the Act; at no time during the period that begins on the earlier of the date of such Pre-Pricing Prospectus and the date such Pre-Pricing Prospectus was filed with the Commission and ends at the time of purchase did or will any Pre-Pricing Prospectus, taken together with the price to public and number of units, as then amended or supplemented, include 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, and at no time during such period did or will any Pre-Pricing Prospectus, as then amended or supplemented, taken together with the price to public and number of units and with any combination of one or more of the then issued Permitted Free Writing Prospectuses, if any, include 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; the Prospectus will comply, as of its date, the date that it is filed with the Commission, the time of purchase, each additional time of purchase, if any, and at all times during which a prospectus is required by the Act to be delivered (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with any sale of Units, in all material respects, with the requirements of the Act (including, without limitation, Section 10(a) of the Act); at no time during the period that begins on the earlier of the date of the Prospectus Supplement and the date the Prospectus Supplement is filed with the Commission and ends at the later of the time of purchase, the latest additional time of purchase, if any, and the end of the period during which a prospectus is required by the Act to be delivered (whether physically or through compliance with Rule 172 under the Act or any similar rule) in connection with any sale of Units did or will the Prospectus, as then amended or supplemented, include 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; at no time during the period that begins on the date of any Permitted Free Writing Prospectus and ends at the time of purchase did or will any Permitted Free Writing Prospectus include 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, or conflict with information contained in the Registration Statement, the Basic Prospectus, the Pre-Pricing Prospectus or the Prospectus that has not been superseded or modified; provided, however, that the Partnership makes no representation or warranty with respect to any statement contained in the Registration Statement, any Pre-Pricing Prospectus, the Prospectus or any Permitted Free Writing Prospectus in reliance upon and in conformity

with information furnished in writing by or on behalf of an Underwriter through you to the Partnership expressly for use in the Registration Statement, such Pre-Pricing Prospectus, the Prospectus or such Permitted Free Writing Prospectus; each Incorporated Document, at the time such document was filed with the Commission or at the time such document became effective, as applicable, complied, in all material respects, with the requirements of the Exchange Act and did not include an untrue statement of 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.

     (c) No Other Prospectus . Prior to the execution of this Agreement, the Partnership has not, directly or indirectly, offered or sold any Units by means of any “prospectus” (within the meaning of the Act) or used any “prospectus” (within the meaning of the Act) in connection with the offer or sale of the Units, in each case other than the Pre-Pricing Prospectuses and the Permitted Free Writing Prospectuses, if any; the Partnership has not, directly or indirectly, prepared, used or referred to any Permitted Free Writing Prospectus except in compliance with Rules 164 and 433 under the Act and will not, directly or indirectly, prepare, use, refer to or distribute any “free writing prospectus” (as defined in Rule 405 under the Act), other than a Permitted Free Writing Prospectus, without the consent of the Representatives; the Partnership has not, directly or indirectly, prepared, used or referred to any Permitted Free Writing Prospectus except in compliance with Rule 433 under the Act; assuming that such Permitted Free Writing Prospectus is accompanied or preceded by the most recent Pre-Pricing Prospectus that contains a price range or the Prospectus, as the case may be, and that such Permitted Free Writing Prospectus is so sent or given after the Registration Statement was filed with the Commission (and after such Permitted Free Writing Prospectus was, if required pursuant to Rule 433(d) under the Act, filed with the Commission), the sending or giving, by any Underwriter, of any Permitted Free Writing Prospectus will satisfy the provisions of Rule 164 or Rule 433 (without reliance on subsections (b), (c) and (d) of Rule 164); the Pre-Pricing Prospectus dated July 26, 2007, is a prospectus that, other than by reason of Rule 433 or Rule 431 under the Act, satisfies the requirements of Section 10 of the Act, including a price range where required by rule; neither the Partnership nor the Underwriters are disqualified, by reason of subsection (f) or (g) of Rule 164 under the Act, from using, in connection with the offer and sale of the Units, “free writing prospectuses” (as defined in Rule 405 under the Act) pursuant to Rules 164 and 433 under the Act; the Partnership is not an “ineligible issuer” (as defined in Rule 405 under the Act) as of the eligibility determination date for purposes of Rules 164 and 433 under the Act with respect to the offering of the Units contemplated by the Registration Statement; the parties hereto agree and understand that the content of any and all “road shows” (as defined in Rule 433 under the Act) related to the offering of the Units contemplated hereby is solely the property of the Partnership.

     (d) Formation of the Regency Parties . Each of the Regency Parties has been duly formed and is validly existing as a limited partnership, limited liability company or corporation, as the case may be, is in good standing under the laws of its respective jurisdiction of formation or incorporation, with full limited partnership, limited liability company or corporate power and authority to own, lease and operate its properties and conduct its business as described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus.

     (e) Qualification of the Regency Parties . Each of the Regency Parties is duly registered or qualified to do business and is in good standing as a foreign limited partnership, limited liability company or corporation, as the case may be, in each jurisdiction where the ownership or leasing of its properties or the conduct of its business requires such qualification, except where the failure to be so registered or qualified and in good standing would not, individually or in the aggregate, (i) have a material adverse effect on the business, properties, financial condition, results of operations 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.

     (f) Ownership of the General Partner Interest in the Partnership . The General Partner is the sole general partner of the Partnership with a 2.0% general partner interest in the Partnership; such general partner interest is duly authorized and validly issued in accordance with the limited partnership agreement of the Partnership (as the same may be amended and restated at or prior to the time of purchase, if applicable, the “ Partnership Agreement ”); and the General Partner owns such general partner interest free and clear of all liens, encumbrances, security, interests, equities, charges or claims except for restrictions on transferability contained in Section 4.8 of the Partnership Agreement and as otherwise described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus.

     (g) Ownership of the Sponsor Units . Immediately prior to the purchase by the Underwriters of any Units pursuant to this Agreement, there will be 28,927,212 Common Units and 19,103,896 Subordinated Units outstanding. To the knowledge of the Regency Parties, the GE Investors own no Common Units. The Subordinated Units consist of 17,763,809 Subordinated Units owned by Regency LP Acquirer LP (the “ LP Acquirer ”), a Delaware limited partnership and wholly-owned subsidiary of GE EFS, 1,116,509 Subordinated Units owned by members of GP LLC’s management and 223,578 Subordinated Units held by two other individuals (together, the “ Sponsor Units ”). All of the Sponsor Units and the limited partner interests represented thereby are 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 Revised Uniform Limited Partnership Act (the “ Delaware LP Act ”) and as otherwise described in the Prospectus under the captions “Material Provisions of the Partnership Agreement of Regency Energy Partners LP — Limited Liability” and “Risk Factors — Risks Related to Our Structure”), and the Incentive Distribution Rights owned by the General Partner are owned free and clear of all liens, encumbrances (except with respect to the restrictions on transferability contained in Section 4.8 of the Partnership Agreement and as otherwise described in the Prospectus), security interests, equities, charges or claims.

     (h) Valid Issuance of the Units . At the time of purchase, or any additional time of purchase, the Units to be sold by the Partnership, 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 and as otherwise described in the Prospectus under the captions “Material Provisions of the Partnership Agreement of Regency Energy Partners LP — Limited Liability” and “Risk Factors — Risks Related to Our Structure.”

     (i) Ownership of the Operating Partnership, Operating Partnership GP and the Subsidiaries . At the time of purchase, the Partnership will own 100% of the outstanding partnership interests, limited liability company interests or capital stock, as the case may be, in the Operating Partnership, the Operating Partnership GP and each of the Subsidiaries (collectively, the “ Operating Subsidiaries ”) free and clear of all liens, encumbrances, security interests, equities, charges and other claims, except for liens created pursuant to the Fourth Amended and Restated Credit Agreement, dated as of December 1, 2004, amended and restated as of August 15, 2006, and further amended on June 15, 2007 and June 29, 2007, by and among the Operating Partnership, as Borrower, the Partnership and the other guarantors named therein and the lenders party thereto (the “ Credit Agreement ”). At the time of purchase, such ownership interests will be duly authorized and validly issued in accordance with the organizational documents of the respective Operating Subsidiaries, and will be fully paid (to the extent required under their respective organizational documents) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware Limited Liability Company Act (the “ Delaware LLC Act ”), in the case of a Delaware limited liability company, or Sections 17-303 and 17-607 of the Delaware LP Act in the case of a Delaware limited partnership). At the time of purchase, in the case of an Operating Subsidiary that is a limited partnership, the general partner interests therein will be duly authorized and validly issued in accordance with the limited partnership agreements of the respective Operating Subsidiaries.

     (j) Ownership of the General Partner . At the time of purchase, GP LLC will own 100% of the outstanding general partner interests in the General Partner and the LP Acquirer will own 100% of the outstanding limited partner interests in the General Partner; all of such interests will be duly authorized and validly issued in accordance with the partnership agreement of the General Partner (as the same may be amended and restated at or prior to the time of purchase, the “ General Partner LP Agreement ”) and will be fully paid (to the extent required under the General Partner LP Agreement) and nonassessable (except as such nonassessability may be affected by Sections 17-303 and 17-607 of the Delaware LP Act); and GP LLC and the LP Acquirer will own such partnership interests free and clear of all liens, encumbrances, security interests, equities, charges or claims, other than as created pursuant to the Credit Agreement in the case of GP LLC.

     (k) Ownership of GP LLC . At the time of purchase, GP Acquirer will own 100% of the outstanding limited liability company interests in GP LLC; all of such interests will be duly authorized and validly issued in accordance with the limited

liability company agreement of GP LLC (as the same may be amended and restated at or prior to the time of purchase, the “ GP LLC Agreement ”) and will be fully paid (to the extent required under the GP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the GP Acquirer will own such limited liability company interests free and clear of all liens, encumbrances, security interests, equities, charges or claims.

     (l) No Other Subsidiaries . Other than its direct or indirect ownership interests in the Operating Subsidiaries, the Partnership does not own, and at the time of purchase 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.

     (m) Authority and Authorization . The Partnership has all requisite power and authority under the Partnership Agreement and the Delaware LP Act 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 Pre-Pricing Prospectus and the Prospectus. At the time of purchase, all partnership, limited liability company and corporate action, as the case may be, required to be taken by the Regency Parties or any of their partners, members or stockholders for the authorization, issuance, sale and delivery of the Units, the Sponsor Units and the Incentive Distribution Rights, the execution and delivery of the Operating Agreements (as defined below) and the consummation of the transactions contemplated by this Agreement shall have been validly taken.

     (n) Conformity of Securities to Description . The Units, when issued and delivered in accordance with the terms of the Partnership Agreement and against payment therefor as provided herein, will conform in all material respects to the descriptions thereof, if any, contained or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and any Permitted Free Writing Prospectus.

     (o) Authorization of Agreement . This Agreement has been duly authorized and validly executed and delivered by each of the Regency Parties party hereto.

     (p) Enforceability of Other Agreements . At or before the time of purchase, and assuming the due authorization, execution and delivery by each party thereto (other than the Regency Parties):

     (i) the Partnership Agreement will have been duly authorized. executed and delivered by the parties thereto and will be a valid and legally binding agreement of the parties thereto and enforceable against the parties thereto in accordance with its terms;

     (ii) the General Partner LP Agreement will have been duly authorized executed and delivered by the parties thereto and will be a valid and legally binding agreement of the parties thereto and enforceable against the parties thereto in accordance with its terms;

     (iii) the GP LLC Agreement will have been duly authorized, executed and delivered by the parties thereto and will be a valid and legally binding agreement of the parties thereto and enforceable against the parties thereto in accordance with its terms;

     (iv) the limited partnership agreement, limited liability company agreement or articles of incorporation, as applicable, of each of the Operating Subsidiaries (together with the Partnership Agreement, the GP LP Agreement and the GP LLC Agreement, the “ Regency Parties Operative Agreements ”) will have been duly authorized, executed and delivered by the parties thereto and will be valid and legally binding agreements of the parties thereto, enforceable against such parties in accordance with their respective terms; and

     (v) the Credit Agreement will have been duly authorized, executed and delivered by the Operating Partnership and the Guarantors named therein and will be a valid and legally binding agreement of the Partnership and the Guarantors named therein, enforceable against the each of them in accordance with its terms;

provided that, with respect to each agreement described in this Section 3(p) , the enforceability thereof may be limited by (A) 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 (B) public policy, applicable laws relating to fiduciary duties and indemnification and an implied covenant of good faith and fair dealing.

     (q) No Default or Conflicts . No Partnership Entity is (A) in violation of its respective formation, governing or other organizational documents, or (B) in breach or in violation of or in default under (nor has any event occurred which with notice, lapse of time or both would result in any breach or violation of, constitute a default under or give the holder of any indebtedness (or a person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a part of such indebtedness under) any indenture, mortgage, deed of trust, bank loan or credit agreement or other evidence of indebtedness, or any license, lease, contract or other agreement or instrument to which it is a party or by which it or any of its properties may be bound or affected, except as disclosed in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus and, in the case of clause B above, for any such breach, violation, default or acceleration that would not have a Material Adverse Effect. The execution, delivery and performance of this Agreement by the Regency Parties party hereto, the issuance and sale of the Units and the consummation of the transactions contemplated hereby will not (I) conflict with, result in any breach or violation of or constitute a default under (nor constitute any event which with notice, lapse of time or both would result in any breach or violation of or constitute a default under) the organizational documents of any of the Partnership Entities, or any federal, state, local or foreign law, regulation or rule or any decree, judgment or order applicable to the any of the Partnership Entities, except as disclosed in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and any Permitted Free Writing Prospectus or (II) conflict with, result in any breach or

violation of or constitute a default under (nor constitute any event which with notice, lapse of time or both would result in any breach or violation of or constitute a default under) or any indenture, mortgage, deed of trust, bank loan or credit agreement or other evidence of indebtedness, or any license, lease, contract or other agreement or instrument to which any Partnership Entity is a party or by which any of them or any of their respective properties may be bound or affected, except as disclosed in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, and for any such breach, violation or default that would not have a Material Adverse Effect.

     (r) No Consents . Except for any approvals, authorizations, consents, orders or filings that, if not obtained or made, would not have a Material Adverse Effect, no approval, authorization, consent or order of or filing with any federal, state, local or foreign governmental or regulatory commission, board, body, authority or agency is required in connection with the (i) execution, delivery and performance of this Agreement by the Regency Parties party hereto or (ii) issuance and sale of the Units or the consummation by the Regency Parties party hereto of the transactions contemplated hereby, other than registration of the Units under the Act, which has been or will be effected, and any necessary qualification under the securities or blue sky laws of the various jurisdictions in which the Units are being offered by the Underwriters or under the rules and regulations of the National Association of Securities Dealers, Inc. (the “ NASD ”).

     (s) No Preemptive Rights, Registration Rights or Options . Except as described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, there are no options, warrants, preemptive rights or other rights to subscribe for or purchase, nor any restriction upon the voting or transfer of, any ownership interests in any Partnership Entity. Except as described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, neither the filing of the Registration Statement 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 Units or other securities of any of the Partnership Entities, other than as provided in the Partnership Agreement or the right of any person to act as an underwriter or as a financial advisor to any of the Regency Parties in connection with the offer and sale of the Units.

     (t) Permits . Each of the Partnership Entities has, or at the time of purchase will have, all licenses, authorizations, consents and approvals of governmental or regulatory authorities (“ permits ”) as are necessary to own or lease its properties and to conduct its business in the manner described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and any Permitted Free Writing Prospectus, subject to such qualifications as may be set forth in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus and except for such permits that, if not obtained, would not have a Material Adverse Effect; none of the Partnership Entities is in violation of, or in default under, or has received notice of any proceedings relating to revocation or modification of, any such permit, except where such violation, default, revocation or modification would not, individually or in the aggregate, have a Material Adverse Effect.

     (u) Disclosure of Certain Items . All legal or governmental proceedings, affiliate transactions, off-balance sheet transactions, contracts, licenses, agreements, leases or documents of a character required to be described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus or to be filed as an exhibit to the Registration Statement have been so described or filed as required.

     (v) Litigation . Except as described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, there are no actions, suits, claims, investigations or proceedings pending or, to the Partnership’s knowledge after due inquiry, threatened, to which any of the Partnership Entities or of which any of their respective properties is or would be subject at law or in equity, before or by any federal, state, local or foreign governmental or regulatory commission, board, body, authority or agency, except any such action, suit, claim, investigation or proceeding that would not result in a judgment, decree or order having, individually or in the aggregate, a Material Adverse Effect or preventing consummation of the transactions contemplated hereby.

     (w) Independent Public Accountants . (i) Deloitte & Touche LLP, whose reports on the consolidated financial statements of the Partnership and the General Partner are included or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus or the Permitted Free Writing Prospectuses, if any, containing an audit report, are independent registered public accountants as required by the Act and by the rules of the Public Company Accounting Oversight Board (the “ PCAOB ”); and (ii) KPMG LLP are independent registered public accountants as required by the Act and by the rules of the PCAOB.

     (x) Financial Statements . The financial statements included or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, together with the related notes and schedules, present fairly the consolidated financial position of the entities purported to be shown thereby as of the dates indicated and the consolidated results of operations, cash flows and changes in partners’ equity of such entities for the periods specified and have been prepared in all material respects in compliance with the requirements of the Act and Exchange Act and in conformity with U.S. generally accepted accounting principles applied on a consistent basis during the periods involved, except to the extent disclosed therein; all pro forma financial statements or data included or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, comply in all material respects with the requirements of the Act (including, without limitation, Regulation S-X under the Act) and the Exchange Act (including, without limitation, Regulation G under the Act), Item 10 under Regulation S-K and Financial Accounting Standards Board Interpretation No. 46, and the assumptions used in the preparation of such pro forma financial statements and data are, in the judgment of the management of GP LLC, reasonable, the pro forma adjustments used therein are appropriate to give effect to the transactions or circumstances described therein and the pro forma adjustments have been properly applied to the historical amounts in the compilation of those statements and data; the other financial and statistical data contained or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free

Writing Prospectuses, if any, are accurately and fairly presented and prepared on a basis consistent with the financial statements and books and records of the Partnership Entities; there are no financial statements (historical or pro forma) that are required to be included or incorporated by reference in the Registration Statement, the Pre-Pricing Prospectus or the Prospectus that are not included or incorporated by reference as required.

     (y) No Material Adverse Change . Except as disclosed in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, subsequent to the respective dates as of which information is given in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, in each case excluding amendments or supplements to the foregoing made after the execution of this Agreement, there has not been (i) any development involving a prospective material adverse change in the business, properties, management, financial condition or results of operations of the Partnership Entities taken as a whole, (ii) any transaction that is material to the Partnership Entities taken as a whole, (iii) any obligation, direct or contingent (including any off-balance sheet obligations), incurred by any Partnership Entities, that is material to the Partnership Entities taken as a whole, (iv) any material change in the capitalization, or material increase in the long-term debt, of the Partnership Entities or (v) any material adverse change in or affecting the general affairs, condition (financial or otherwise), business, prospects, assets or results of operations of the Partnership Entities taken as a whole. None of the Partnership Entities has sustained since the date of the last audited financial statements included in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus any material loss or interference with its respective business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree except as described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and any Permitted Free Writing Prospectus.

     (z) Lock-Up Agreement . The Partnership has obtained, or will obtain prior to the time of purchase, for the benefit of the Underwriters the agreement (a “ Lock-Up Agreement ”), in the form set forth as Exhibit A hereto, of each of GP LLC’s directors and officers, and each holder of the Sponsor Units, except for two individuals holding 223,578 Subordinated Units.

     (aa) Investment Company/Public Utility Holding Company . None of the Partnership Entities is now and, after giving effect to the offering and sale of the Units, will not be an “investment company” or an entity “controlled” by an “investment company,” as such terms are defined in the Investment Company Act of 1940, as amended (the “ Investment Company Act ”).

     (bb) Title to Properties . At the time of purchase, each Operating Subsidiary will have good and marketable title to all real property (excluding easements or rights-of-way) described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, as being owned by each of them, free and clear of all liens, encumbrances, security interests, equities, charges or claims, except (i) as described, and subject to the limitations contained, in the Registration

Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, (ii) that arise under or are expressly permitted by the Credit Agreement, (iii) liens or security interests securing indebtedness expressly assumed by the Operating Subsidiaries in connection with the initial public offering of the Partnership or (iv) 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 in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any. All the real property described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, as being held under lease by any Regency Party is held thereby under valid, subsisting and enforceable leases and with such exceptions as do not materially interfere with the use of such properties in the manner in which such properties are used in the business of the Partnership as described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any.

     (cc) Rights of Way . At the time of purchase, each of the Partnership Entities will have such consents, easements, rights-of-way, permits or licenses from each person (collectively, “ rights-of-way ”) as are necessary to conduct its business in the manner described, and subject to the limitations contained, in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, except for (i) qualifications, reservations and encumbrances as may be set forth in the Prospectus that would not have a Material Adverse Effect and (ii) such rights-of-way that, if not obtained, would not have, individually or in the aggregate, a Material Adverse Effect; other than as set forth, and subject to the limitations contained, in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, each of the Partnership Entities has, or at the time of purchase following consummation of the transactions contemplated hereby will have, fulfilled and performed, in all material respects, its obligations with respect to such rights-of-way and no event has occurred that allows, or after notice or lapse of time would allow, revocation or termination thereof or would result in any impairment of the rights of the holder of any such rights-of-way, except for such revocations, terminations and impairments that would not have a Material Adverse Effect; and, except as described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, none of such rights-of-way contains any restriction that is materially burdensome to the Partnership Entities, taken as a whole.

     (dd) Intellectual Property . The Partnership Entities own, or have obtained valid and enforceable licenses for, or other rights to use, the inventions, patent applications, patents, trademarks (both registered and unregistered), tradenames, service names, copyrights, trade secrets and other proprietary information described in the Registration Statement, the Pre-Pricing Prospectus, the Prospectus and the Permitted Free Writing Prospectuses, if any, as being owned or licensed by them or which are necessary for the conduct of their respective businesses, except where the failure to own, license or have such rights would not, individually or in the aggregate, have a Material Adverse Effect (collectively, “ Intellectual Property ”).

     (ee) Labor Matters . Except for matters that would not, individually or in the aggregate, have a Material Adverse Effect on the Partnership Entities taken as a whole, (i) there is (A) no unfair labor practice complaint pending or, to the Partnership’s knowledge, threatened against any of the Partnership Entities, and no grievance or arbitration proceeding arising out of or under collective bargaining agreements is pending or, to the Partnership’s knowledge, threatened, (B) no strike, labor dispute, slowdown or stoppage pending or, to the Partnership’s knowledge, threatened against any of the Partnership Entities, (C) no union representation dispute currently existing concerning the employees of any of the Partnership Entities, (D) no, nor as there been in the past, any violation of any federal, state, local or foreign law relating to discrimination in the hiring, promotion or pay of employees, any applicable wage or hour laws or any provision of the Employee Retirement Income Security Act of 1974 (“ ERISA ”) or the rules and regulations promulgated thereunder concerning the employees of any of the Partnership Entities and (E) to the Partnership’s knowledge, no union organizing activities are currently taking place concerning the employees of the any of the Partnership Entities.

     (ff) Environmental Compliance . Except as described in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, each of the Partnership Entities and their respective properties, assets and operations are in compliance with, and hold all permits, authorizations and approvals required under, Environmental Laws (as defined below), except to the extent that failure to so comply or to hold such permits, authorizations or approvals would not, individually or in the aggregate, have a Material Adverse Effect; except as disclosed in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus, there are no past, present or, to the Partnership’s knowledge, reasonably anticipated future events, conditions, circumstances, activities, practices, actions, omissions or plans that could reasonably be expected to give rise to any costs or liabilities to any Partnership Entity, except as would not, individually or in the aggregate, have a Material Adverse Effect; except as disclosed in the Registration Statement, the Pre-Pricing Prospectus and the Prospectus and except as would not, individually or in the aggregate, have a Material Adverse Effect, no Partnership Entity (i) is the subject of any investigation, (ii) has received any notice or claim, (iii) is a party to or affected by any pending or, to the knowledge of any Partnership Entity, threatened action, suit or proceeding, (iv) is bound by any judgment, decree or order or (v) has entered into any agreement, in each case relating to any alleged violation of any Environmental Law or any actual or alleged release or threatened release or cleanup at any location of any Hazardous Materials. As used herein, “ Environmental Law ” means any federal, state or local laws or regulations relating to the protection of human health and safety and the environment, including those imposing liability or standards of conduct concerning any Hazardous Materials, and “ Hazardous Materials ” means (A) any “hazardous substance” as defined in the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended, (B) any “hazardous waste” as defined in the Resource Conservation and Recovery Act, as amended, (C) any petroleum or petroleum product, (D) any polychlorinated biphenyl and (E) any pollutant or contaminant or hazardous, dangerous or toxic chemical, material, waste or substance regulated under or within the meaning of any other Environmental Law.

     (gg) Environmental Compliance Review . In the ordinary course of its business, the Partnership Entities conduct a periodic review of the effect of the Environmental Laws on their business, operations and properties, in the course of which they identify and evaluate associated costs and liabilities (including, without limitation, any capital or operating expenditure