EXHIBIT 5.1

                                 September 29, 1999



Plains All American Pipeline, L.P.
500 Dallas
Suite 700
Houston, Texas 77002

Gentlemen:

          We have acted as counsel to Plains All American Pipeline, L.P., a
Delaware limited partnership (the "Partnership"), and Plains All American Inc.,
a Delaware corporation and the general partner of the Partnership, in connection
with the registration under the Securities Act of 1933, as amended (the "Act"),
of the offering and sale of up to an aggregate of 2,600,000 common units
representing limited partner interests in the Partnership (the "Common Units").

          As the basis for the opinion hereinafter expressed, we have examined
such statutes, regulations, corporate records and documents, certificates of
corporate and public officials, and other instruments as we have deemed
necessary or advisable for the purposes of this opinion.  In such examination we
have assumed the authenticity of all documents submitted to us as originals and
the conformity with the original documents of all documents submitted to us as
copies.

          Based on the foregoing and on such legal considerations as we deem
relevant, we are of the opinion that:

     1.   The Partnership has been duly formed and is validly existing as a
limited partnership under the Delaware Revised Uniform Limited Partnership Act.

     2.   The Common Units will, when issued and paid for as described in the
Partnership's Registration Statement on Form S-1 (File No. 333-86907) relating
to the Common Units, as amended (the "Registration Statement"), be duly
authorized, validly issued, fully paid and nonassessable, except as such
nonassessability may be affected by the matters described in the prospectus
included in the Registration Statement (the "Prospectus") under the caption "The
Partnership Agreement--Limited Liability."

     We hereby consent to the use of this opinion as an exhibit to the
Registration Statement and to the reference to us under the caption "Validity of
the Common Units" in the Prospectus.

                              Very truly yours,


                              /s/ Andrews & Kurth L.L.P.
                              --------------------------------
                              Andrews & Kurth L.L.P.