EXHIBIT 5.1
 
                                                                      Date
 
WAI, Inc.
100 West Fifth Street
Suite 1000
Tulsa, Oklahoma 74103
 
Ladies and Gentlemen:
 
  We are acting as special counsel to WAI, Inc., an Oklahoma corporation (the
"Company"), in connection with the preparation and filing of the Registration
Statement on Form S-4 (the "Registration Statement") of the Company relating
to the registration under the Securities Act of 1933, as amended (the
"Securities Act"), of shares of the Company's Common Stock, par value $.01 per
share (the "Common Stock"), to be issued pursuant to the terms of an
agreement, dated December 12, 1996, as amended and restated as of May 19, 1997
(the "Agreement"), among the Company, ONEOK Inc. ("ONEOK") and Western
Resources, Inc. pursuant to which (i) ONEOK will merge with and into the
Company with the Company continuing as the surviving corporation, and (ii) all
shares of the common stock, no par value, of ONEOK will be converted on a one-
for-one basis into shares of the Common Stock pursuant to the provisions of
the Agreement.
 
  We have examined the originals, or certified, conformed or reproduction
copies, of all such records, agreements, instruments and documents as we have
deemed relevant or necessary as the basis for the opinions hereinafter
expressed. In all such examinations, we have assumed the genuineness of all
signatures on original or certified copies and the conformity to original or
certified copies of all copies submitted to us as conformed or reproduction
copies. As to various questions of fact relevant to such opinions, we have
relied upon certificates and statements of public officials and officers or
representatives of the Company and of others.
 
  Based upon the foregoing and subject to the limitations set forth herein, it
is our opinion that the shares of the Common Stock to be issued pursuant to
the Agreement have been duly authorized and will be (when issued pursuant to
the Agreement) validly issued, fully paid and non-assessable.
 
  This opinion is limited to the laws of the State of Oklahoma.
   
  The opinion expressed herein is solely for your benefit and the benefit of
the holders of shares of outstanding common stock of ONEOK and may not be
relied upon in any manner for any purpose except as specifically provided for
herein.     
 
                                          Very truly yours,