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                                                                       EXHIBIT 5


June 7, 2001

The Williams Companies, Inc.
One Williams Center
Tulsa, Oklahoma 74172

Gentlemen:

         You have requested me, as General Counsel of The Williams Companies,
Inc., to render my opinion regarding certain matters in connection with the
preparation and filing of a registration statement by The Williams Companies,
Inc. (the "Company") on Form S-3 (the "Registration Statement") under the
Securities Act of 1933, as amended, with respect to $75,943,750 initial offering
price of additional debt securities ("Securities") pursuant to Rule 462(b) under
the Securities Act of 1933, as amended. The Securities are to be issued from
time to time as senior indebtedness of the Company under an indenture between
the Company and Bank One Trust Company, as trustee (the "Indenture").

         I am familiar with the Certificate of Incorporation and the By-laws,
each as amended to date, of the Company and have examined the originals, or
copies certified or otherwise identified to my satisfaction, of corporate
records of the Company, statutes and other instruments and documents as the
basis for the opinion expressed herein. In addition, I am, or someone under my
supervision is, familiar with the forms of the Indenture and the Securities.

         Based upon the foregoing, and having regard for such legal
considerations as I have deemed relevant, I am of the opinion that, when the
remaining terms are set by an officer of the Company pursuant to the authority
granted such officer by the Board of Directors of the Company, the Indenture has
been duly executed and delivered and the Securities have been duly issued in
accordance with the provisions of the Indenture and duly paid for by the
purchasers thereof, all required corporate action will have been taken with
respect to the issuance and sale of the Securities, and the Securities will have
been validly issued and will constitute valid and binding obligations of the
Company enforceable in accordance with their terms, except as enforceability may
be limited by bankruptcy, insolvency, reorganization or other laws relative to
or affecting generally the enforcement of creditor's rights and by principles of
equity.

         In connection with my opinions expressed above, I have assumed that, at
or prior to the time of the delivery of any such Security, the Registration
Statement has been declared effective, that the authorization of such Securities
will not have been modified or rescinded and there will not have occurred any
change in law affecting the validity or enforceability of such Security. I have
also assumed that none of the terms of any Security to be established subsequent
to the date hereof nor the issuance and delivery of such Security, nor the
compliance by the Company with the terms of such Security, will violate any
applicable law or will result in a violation of any provision of any instrument
or agreement then binding upon the Company, or any restriction imposed by any
court or governmental body having jurisdiction over the Company.

         I am a member of the Bar of the State of New York and the foregoing
opinion is limited to the laws of the State of New York, the federal laws of the
United States of America and the General Corporation Law of the State of
Delaware.


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The Williams Companies, Inc.
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         I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to the undersigned appearing under
the caption "Legal Matters" in the related Prospectus.

                                                     Very truly yours,

                                                     /s/ WILLIAM G. VON GLAHN

                                                     William G. von Glahn