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                                                                    EXHIBIT 10.2

                                    AGREEMENT

        AGREEMENT, dated as of May 4, 2000, by and between VOICESTREAM WIRELESS
CORPORATION (f/k/a VoiceStream Wireless Holding Corporation), a Delaware
corporation ("VoiceStream") and TELEPHONE AND DATA SYSTEMS, INC., a Delaware
corporation ("TDS");

        WHEREAS, VoiceStream has entered into a Voting Agreement ("Voting
Agreement") dated as of February 25, 2000, together with certain stockholders of
VoiceStream set forth on Schedule I thereof ("Stockholders");

        WHEREAS, all capitalized terms used herein and not otherwise defined
shall have the meanings set forth in the Voting Agreement;

        WHEREAS, in the Voting Agreement, the Stockholders and VoiceStream have
agreed that, at the time of the closing of the Aerial Reorganization, TDS and
VoiceStream shall execute and deliver this Agreement to evidence the admission
of TDS as a party to the Voting Agreement;

        WHEREAS, the Aerial Reorganization is being consummated concurrently
with the execution of this Agreement;

        NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and agreements set forth herein, the parties hereto agree as follows:

        1.      TDS hereby accepts and agrees to all of the terms and conditions
                of the Voting Agreement and agrees to become a party to the
                Voting Agreement as a Stockholder effective immediately.

        2.      The Voting Agreement shall not in any way limit, amend or modify
                any of the terms or provisions of the Investor Agreement dated
                the date hereof among TDS, VS Washington Corporation and
                VoiceStream.

        3.      VoiceStream, by action of its Board of Directors, shall appoint
                a Qualified TDS Designee to the Board of Directors of
                VoiceStream on the later of (i) the date hereof or (ii) promptly
                after TDS designates a Qualified TDS Designee.

        4.      This Agreement shall become effective as of the Effective Time
                of the Aerial Reorganization and shall supersede the Parent
                Stockholder Agreement, dated as of September 17, 1999, among
                Aerial, TDS, VoiceStream and VS Washington Corporation (f/k/a
                VoiceStream Wireless Corporation) and the individuals and
                entities set forth on Schedule I thereto, which shall terminate
                by its terms at such time.

        5.      The number of Shares Beneficially Owned by TDS as of the date of
                this Agreement is 35,570,493 Shares.


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        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the day and year first above written.

        VOICESTREAM WIRELESS CORPORATION


        By:    /s/ Alan R. Bender
               -------------------------
        Name:  Alan R. Bender
        Title: Executive Vice President


        TELEPHONE AND DATA SYSTEMS, INC.


        By:    /s/ Leroy T. Carlson, Jr.
               -------------------------
        Name:  Leroy T. Carlson, Jr.
        Title: President






        SIGNATURE PAGE TO ACCEPTANCE BY TELEPHONE AND DATA SYSTEMS, INC.
              OF VOICESTREAM WIRELESS CORPORATION VOTING AGREEMENT



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