EXHIBIT 5.1

                            GLAST, PHILLIPS & MURRAY
                           A PROFESSIONAL CORPORATION

                                                       2200 ONE GALLERIA TOWER
                            ATTORNEYS AND COUNSELORS   13355 NOEL ROAD, L.B. 48
RONALD L. BROWN, P.C.                                  DALLAS, TEXAS 75240-6657

DIRECT DIAL NUMBER:                                    TELEPHONE: (972) 419-8300
(972) 419-8302                                            FAX: (972) 419-8329
e-mail: rbrown@gpm-law.com

                                November 29, 2000

Greenbriar Corporation
4265 Kellway Circle
Addison, Texas 75244

         Re:      Form S-8 Registration  Statement  relating to the registration
                  of  500,000  shares  of  common  stock,  $0.01  par  value  of
                  Greenbriar Corporation pursuant to the 2000 Stock Option Plan.

Gentlemen:

         We  are  acting  as  counsel  for  Greenbriar  Corporation,   a  Nevada
corporation (the "Company"),  in connection with the filing under the Securities
Act of 1933, as amended, of a Registration Statement for the Company on Form S-8
filed with the Securities  and Exchange  Commission  ("SEC") (the  "Registration
Statement"),  covering an aggregate of 500,000  shares (the  "Shares") of common
stock, par value $0.01 per share (the "Common Stock"), of the Company which will
be issued pursuant to the 2000 Stock Option Plan.

         In  that  connection,  we  have  examined  the  Form  S-8  Registration
Statement  in the form to be filed with the SEC. We have also  examined  and are
familiar  with the originals or  authenticated  copies of all corporate or other
documents,  records and instruments that we have deemed necessary or appropriate
to enable us to render the opinion expressed below.

         We have assumed that all  signatures on all  documents  presented to us
are genuine,  that all  documents  submitted to us as originals are accurate and
complete,  that all  documents  submitted  to us as copies are true and  correct
copies  of the  originals  thereof,  that all  information  submitted  to us was
accurate and complete and that all persons executing and delivering originals or
copies of  documents  examined by us were  competent to execute and deliver such
documents.  In addition,  we have assumed that the Shares will not be issued for
consideration  equal to less  than the par  value  thereof  and that the form of
consideration  to be  received  by the  Company  for the  Shares  will be lawful
consideration under the Nevada Revised Statutes.


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         Based  on  the   foregoing   and   having  due  regard  for  the  legal
considerations  we deem relevant,  we are of the opinion that the Shares, or any
portion thereof, when issued as described in the Registration Statement, will be
validly issued by the Company, fully paid and nonassessable.

         This  opinion  is  limited  in all  respects  to the laws of the United
States of America and the general corporation laws of the State of Nevada.

         This opinion may be filed as an exhibit to the Registration Statement.

                                                Sincerely,

                                                GLAST, PHILLIPS & MURRAY, P.C.


                                                /s/ Glast, Phillips & Murray





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