exv5w1

Exhibit 5.1

April 2, 2007

Regency Energy Partners LP
1700 Pacific, Suite 2900
Dallas, Texas 75201

Ladies and Gentlemen:

We have acted as counsel for Regency Energy Partners LP, a Delaware limited partnership (the “Partnership”) with respect to the preparation of the Registration Statement on Form S-3 (the “Registration Statement”) filed on the date hereof with the Securities and Exchange Commission (the “Commission”) in connection with the registration by the Partnership under the Securities Act of 1933, as amended (the “Securities Act”), of the offer and sale by the Partnership or by selling unitholders from time to time, pursuant to Rule 415 under the Securities Act, of common units representing limited partner interests in the Partnership (the “Common Units”).

We have also participated in the preparation of the Prospectuses (the “Prospectuses”) contained in the Registration Statement to which this opinion is an exhibit. Capitalized terms not defined herein shall have the meanings ascribed to them in the Prospectuses.

We have examined the Registration Statement, including the Prospectuses, the First Amended and Restated Agreement of Limited Partnership of the Partnership, as amended (the “Partnership Agreement”), the Certificate of Limited Partnership (the “Certificate”) filed with the Secretary of State of Delaware pursuant to the Delaware Revised Uniform Limited Partnership Act in connection with the formation of the Partnership and such other documents as we have deemed necessary or appropriate for purposes of this opinion. In addition, we have reviewed certain certificates of officers of the general partner of the Partnership and of public officials, and we have relied on such certificates with respect to certain factual matters that we have not independently established.

In connection with this opinion, we have assumed that :

	(1)		the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective;

	(2)		a Prospectus Supplement will be prepared and filed with the Commission describing the Common Units offered thereby;

	(3)		all Common Units will be issued and sold in compliance with applicable federal and state securities laws and in the manner stated in the Registration Statement and the appropriate Prospectus Supplement; and

	(4)		a definitive purchase, underwriting or similar agreement with respect to any Common Units offered will have been duly authorized and validly executed and delivered by the Partnership and the other parties thereto.

Based upon and subject to the foregoing, we are of the opinion that (i) the Partnership has taken all necessary action to approve the issuance of the Common Units, the terms of the offering thereof and related matters and (ii) the Common Units have been issued and delivered in accordance with the terms of the applicable definitive purchase, underwriting or similar agreement approved by the Partnership upon payment of the consideration thereof or provided for therein, then the Common Units will be validly issued, fully paid and non-assessable.

The opinions expressed herein are qualified in the following respects:

	(1)		We have assumed, without independent verification, that the certificates for the Common Units will conform to the specimens thereof examined by us and will have been duly countersigned by a transfer agent and duly registered by a registrar of the Common Units.

	(2)		We have assumed that (i) each document submitted to us for review is accurate and complete, each such document that is an original is authentic, each such document that is a copy conforms to an authentic original and all signatures on each such document are genuine and (ii) each certificate from governmental officials reviewed by us is accurate, complete and authentic, and all official public records are accurate and complete.