EXHIBIT 5

                       [SIDLEY AUSTIN BROWN & WOOD LETTERHEAD]



                                October 16, 2001


Telephone and Data Systems, Inc.
30 North LaSalle Street
Suite 4000
Chicago, Illinois 60602

       Re:   $1,000,000,000 in Debt Securities of Telephone and
             Data Systems, Inc.
             --------------------------------------------------
Ladies and Gentlemen:

     We are counsel to Telephone and Data Systems, Inc., a Delaware corporation
(the "Company"), and have represented the Company with respect to the
Registration Statement on Form S-3 (the "Registration Statement") being filed by
the Company with the Securities and Exchange Commission (the "Commission") under
the Securities Act of 1933, as amended (the "Securities Act"), relating to the
registration of $1,000,000,000 in debt securities of the Company to be issued
under an Indenture (the "Indenture") to be entered between the Company and BNY
Midwest Trust Company (the "Debt Securities").

     In rendering this opinion letter, we have examined and relied upon a copy
of the Registration Statement. We have also examined originals, or copies of
originals certified to our satisfaction, of such agreements, documents,
certificates and other statements of governmental officials and other
instruments, and have examined such questions of law and have satisfied
ourselves as to such matters of fact, as we have considered relevant and
necessary as a basis for this opinion.

     Based on the foregoing, it is our opinion that:

     1. The Company is duly incorporated and validly existing under the laws of
        the State of Delaware.

     2. The Company has the corporate power and authority to execute and deliver
        the Indenture and to authorize and sell the Debt Securities.




SIDLEY AUSTIN BROWN & WOOD                                           CHICAGO

Telephone and Data Systems, Inc.
October 16, 2001
Page 2

     3. Each series of Debt Securities will be legally issued and binding
        obligations of the Company (except to the extent enforceability may be
        limited by applicable bankruptcy, insolvency, reorganization,
        moratorium, fraudulent transfer or other similar laws affecting the
        enforcement of creditors' rights generally and by the effect of general
        principles of equity, regardless of whether enforceability is considered
        in a proceeding in equity or at law) when (i) the Registration
        Statement, as finally amended (including any necessary post-effective
        amendments), shall have become effective under the Securities Act, (ii)
        the Indenture (including any necessary supplemental indenture) shall
        have been duly executed and delivered by the Company and the Trustee;
        (iii) the Indenture shall have been duly qualified under the Trust
        Indenture Act of 1939, as amended; (iv) the Company's Board of Directors
        or a duly authorized committee thereof shall have duly adopted final
        resolutions authorizing the issuance and sale of such series of Debt
        Securities under the Indenture as contemplated by the Registration
        Statement; (v) a Prospectus Supplement with the respect to such series
        of Debt Securities shall have been filed with the Commission pursuant to
        Rule 424 under the Securities Act; and (vi) such series of Debt
        Securities shall have been duly executed and authenticated as provided
        in the Indenture and such resolutions and shall have been duly delivered
        to the purchasers thereof against payment of the agreed consideration
        therefor.

     For the purposes of this opinion letter, we have assumed that, at the time
of the issuance, sale and delivery of each series of Debt Securities, the
authorization thereof by the Company will not have been modified or rescinded,
and there will not have occurred any change in law affecting the validity,
legally binding character or enforceability thereof; and the Indenture will not
have been modified or amended.

     We do not find it necessary for the purposes of this opinion letter to
cover, and accordingly we express no opinion as to, the application of the
securities or blue sky laws of the various states or the District of Columbia to
the sale of the Debt Securities.

     This opinion letter is limited to the General Corporation Law of the State
of Delaware, the laws of the State of Illinois and the federal laws of the
United States of America (excluding the Federal Communications Act, as amended,
and any rules and regulations in effective thereunder) to the extent applicable.

     Walter C.D. Carlson, a director of the Company and of a subsidiary of the
Company, Michael G. Hron, the General Counsel and an Assistant Secretary of the
Company and a subsidiary of the Company and an Assistant Secretary of certain
subsidiaries of the Company, William S. DeCarlo, the Assistant General Counsel
and an Assistant Secretary of the Company and an Assistant Secretary of certain
subsidiaries


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SIDLEY AUSTIN BROWN & WOOD                                           CHICAGO

Telephone and Data Systems, Inc.
October 16, 2001
Page 3


of the Company, and Stephen P. Fitzell, the Assistant General Counsel and an
Assistant Secretary of certain subsidiaries of the Company, are members of that
law firm. Walter C.D. Carlson is also a trustee of a voting trust which controls
the Company.

     We hereby consent to the filing of this opinion letter as an Exhibit to the
Registration Statement and to all references to our firm included in or made a
part of the Registration Statement.



                                         Very truly yours,


                                         /s/ Sidley Austin Brown & Wood



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