UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-Q/A

|X| QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE
    ACT OF 1934

                  For the quarterly period ended September 30, 2000.

                                       OR

|_| TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE
    ACT OF 1934

                       For the transition period from   to

                        Commission File Number 000-23387

                                 TELIGENT, INC.
             (Exact Name of Registrant as Specified in its Charter)

                   Delaware                              54-1866562
       (State or other jurisdiction of     (I.R.S. Employer Identification No.)
        incorporation or organization)

             460 Herndon Parkway                            20170
                  Suite 100                               (Zip Code)
                 Herndon, VA
   (Address of principal executive offices)

       Registrant's telephone number, including area code: (703) 326-4400

     Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days: Yes |_| No|X|.

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of the registrant's knowledge, in the definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K|_|.

     The number of shares outstanding of each of the registrant's classes of
common stock as of November 6, 2000 was as follows:

                        Common Stock, Class A 42,423,082
                        Common Stock, Class B 21,260,610
<PAGE>

Item 6. Exhibits and Reports on Form 10-Q/A

        (a) Exhibits

10.1    Agreement, dated as of May 9, 2000, by and between Level 3
        Communications, LLC and Teligent Services Inc., as amended. [Portions of
        the document have been omitted pursuant to a request for confidential
        treatment requested through November 1, 2005.]

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<PAGE>


                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                        TELIGENT, INC.
                                        (Registrant)


Date:  April 1, 2002                    By: /s/ James V. Continenza
                                           -----------------------------
                                           James V. Continenza
                                           Chief Operating Officer and Director
                                           (Principal Executive Officer)

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<PAGE>

                             EXHIBIT INDEX

Exhibit No.     Description of Exhibit
-----------     ----------------------

10.1            Agreement, dated as of May 9, 2000, by and between Level 3
                Communications, LLC and Teligent Services Inc., as amended.
                [Portions of the document have been omitted pursuant to a
                request for confidential treatment requested through November 1,
                2005.]

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