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                      SECURITIES AND EXCHANGE COMMISSION
                      ----------------------------------
                             Washington, D.C. 20549

                             _______________________


                                   FORM 10-KA
[X]            ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)
                    OF THE SECURITIES EXCHANGE ACT OF 1934
                    For the Fiscal Year Ended  July 31, 1999

                                       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:

                              AMERICAN TELESOURCE
                              INTERNATIONAL, INC.
             (Exact Name of Registrant as Specified in its Charter)

               Delaware                               74-2849995
       (State of Incorporation)                    (I.R.S.Employer
                                                   Identification No.)

          6000 Northwest Parkway, Suite 110
                 San Antonio, Texas
                (Address of Principal                     78249
                  Executive Office)                     (Zip Code)


                                 (210) 547-1000
              (Registrant's Telephone Number, Including Area Code)

          Securities Registered Pursuant to Section 12(b) of the Act:
                                      None

          Securities Registered Pursuant to Section 12(g) of the Act:
                    Common Stock, Par Value $0.001 Per Share
                                (Title of Class)

                            _______________________
     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 [X] No

     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 herein,
and will not be contained, to the best of Registrant's knowledge, in 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 aggregate market value of the Registrant's outstanding Common Stock
held by non-affiliates of the Registrant at October 25, 1999, was approximately
$41,558,696. There were 48,685,287 shares of Common Stock outstanding at October
25, 1999, and the closing sales price on the NASDAQ/OTCB for our Common Stock
was $0.92 on such date.

                     DOCUMENTS INCORPORATED BY REFERENCE:

     Portions of the Registrant's Proxy Statement for the 1999 Annual Meeting of
Stockholders to be held in December 1999, are incorporated by reference in Part
III hereof.

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        This Form 10-K/A is being filed solely for the purposes of complying
with the requirements for confidential treatment of certain of our exhibits to
our Form 10-K as originally filed on October 26, 1999 and amended on April 14,
2000, July 14, 2000 and August 25, 2000. These exhibits are attached as revised
exhibits in this filing.
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                                    PART IV
                                    -------

ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K



(c)  Exhibits

3.1  Amended and Restated Certificate of Incorporation of American TeleSource
     International, Inc., a Delaware corporation (Exhibit 3.3 to Amendment No. 2
     to Registration statement on Form 10 (No. 333-05557) of ATSI filed on
     September 11, 1997)

3.2  Amended and Restated Bylaws of American TeleSource International, Inc.
     (Exhibit to Amended Annual Report on Form 10-K for year ended July 31, 1999
     filed April 13, 2000)

4.1  Certificate of Designation, Preferences and Rights of 10% Series A
     Cumulative Convertible Preferred Stock (Exhibit 10.43 to Annual Report on
     Form 10-K for year ending July 31, 1999 filed on October 26, 1999)

4.2  Certificate of Designation, Preferences and Rights of 6% Series B
     Cumulative Convertible Preferred Stock (Exhibit 10.34 to Registration
     statement on Form S-3 (No. 333-84115) filed August 18, 1999)

4.3  Certificate of Designation, Preferences and Rights of 6% Series C
     Cumulative Convertible Preferred Stock (Exhibit 10.40 to Registration
     statement on Form S-3 (No. 333-84115) filed October 26, 1999)

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4.4  Securities Purchase Agreement between The Shaar Fund Ltd. and ATSI dated
     July 2, 1999 (Exhibit 10.33 to Registration statement on Form S-3 (No. 333-
     84115) filed August 18, 1999)

4.5  Common Stock Purchase Warrant issued to The Shaar Fund Ltd. by ATSI dated
     July 2, 1999 (Exhibit 10.35 to Registration statement on Form S-3 (No. 333-
     84115) filed August 18, 1999)

4.6  Registration Rights Agreement between The Shaar Fund Ltd. and ATSI dated
     July 2, 1999 (Exhibit 10.36 to Registration statement on Form S-3 (No. 333-
     84115) filed August 18, 1999)

4.7  Securities Purchase Agreement between The Shaar Fund Ltd. and ATSI dated
     September 24, 1999 (Exhibit 10.39 to Registration statement on Form S-3
     (No. 333-84115) filed October 26, 1999)

4.8  Common Stock Purchase Warrant issued to The Shaar Fund Ltd. by ATSI dated
     September 24, 1999 (Exhibit 10.41 to Registration statement on Form S-3
     (No. 333-84115) filed October 26, 1999)

4.9  Registration Rights Agreement between The Shaar Fund Ltd. and ATSI dated
     September 24, 1999 (Exhibit 10.42 to Registration statement on Form S-3
     (No. 333-84115) filed October 26, 1999)

4.10 Amended and Restated 1997 Option Plan (Exhibit 10.30 to Registration
     statement on Form S-4 (No. 333-47511) filed March 6, 1998)

4.11 Form of 1997 Option Plan Agreement (Exhibit 10.7 to Registration statement
     on Form 10 (No. 000-23007) filed August 22, 1997)

4.12 American TeleSource International, Inc. 1998 Stock Option Plan (Exhibit 4.7
     to Registration statement on Form S-8 filed January 11, 2000)

10.1 Agreement with SATMEX (Agreement #095-1) (Exhibit 10.31 to Annual Report on
     Form 10-K for year ended July 31, 1998 (No. 000-23007))

10.2 Agreement with SATMEX (Agreement #094-1) (Exhibit 10.32 to Annual Report on
     Form 10-K for year ended July 31, 1998 (No. 000-23007))

10.3 Amendment to Agreement #094-1 with SATMEX (Exhibit to this Amended Annual
     Report on Form 10-K for year ended July 31, 1999 filed August 25, 2000)
     Confidential treatment requested for portions of this document omitted
materials have been filed separately with the Commission.

10.4 Amendment to Agreement #095-1 with SATMEX (Exhibit to this Amended Annual
     Report on Form 10-K for year ended July 31, 1999 filed September 8, 2000)
     Confidential treatment requested for portions of this document. Omitted
     materials have been filed separately with the Commission.

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10.5  Bestel Fiber Lease (Exhibit to this Amended Annual Report on Form 10-K for
      year ended July 31, 1999 filed April 14, 2000)

10.6  Addendum to Fiber Lease with Bestel, S.A. de C.V. (Exhibit to this Amended
      Annual Report on Form 10-K for year ended July 31, 1999 filed September 8,
      2000) Confidential treatment requested for portions of this document.
      Omitted materials filed separately with the Commission.

10.7  Lease Finance Agreements between IBM de Mexico and ATSI-Mexico (Exhibit
      10.21 to Amendment No. 1 to Registration statement on Form 10 (No. 023007)
      filed September 11, 1997)

10.8  Amendments to Lease Finance Agreements between IBM de Mexico and ATSI-
      Mexico (to be filed)

10.9  Master Lease Agreement with NTFC (Exhibit to this Amended Annual Report on
      Form 10-K for year ended July 31, 1999 filed April 14, 2000)

10.10 BancBoston Master Lease Agreement (Exhibit to this Amended Annual Report
      on Form 10-K for year ended July 31, 1999 filed September 8, 2000)
      Confidential treatment requested for portions of this document. Omitted
      materials filed separately with the Commission.

10.11 Employment Agreement with Arthur L. Smith dated - February 28,
      1997(Exhibit 10.16 to Registration statement on Form 10 (No. 333-05557)
      filed August 22, 1997)

10.12 Employment Agreement with Arthur L. Smith dated September 24, 1998
      (Exhibit to this Amended Annual Report on Form 10-K filed April 14,
      2000)

10.13 Employment Agreement with Craig K. Clement dated February 28, 1997
      (Exhibit 10.18 to Registration statement on Form 10 (No. 333-05557) filed
      August 22, 1997)

10.14 Employment Agreement with Craig K. Clement dated January 1, 2000 (Exhibit
      to this Amended Annual Report on Form 10-K for year ended July 31, 1999
      filed April 14, 2000)

10.15 Employment Agreement with Sandra Poole-Christal dated January 1, 1998
      (Exhibit to this Amended Annual Report on Form 10-K for year ended July
      31, 1999 filed April 14, 2000)

10.16 Employment Agreement with Charles R. Poole dated February 28, 1997
      (Exhibit 10.20 to Registration statement on Form 10 (No. 333-05557) filed
      August 22, 1997)

10.17 Employment Agreement with Charles R. Poole dated September 24, 1998
      (Exhibit to this Amended Annual Report on Form 10-K filed April 14,
      2000)

10.18 Employment Agreement with H. Douglas Saathoff dated February 28,
      1997(Exhibit 10.17 to Registration statement on Form 10 (No. 333-05557)
      filed August 22, 1997)

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10.19  Employment Agreement with H. Douglas Saathoff dated January 1, 2000
       (Exhibit to this Amended Annual Report on Form 10-K for year ended July
       31, 1999 filed April 14, 2000)

10.20  Office Space Lease Agreement (Exhibit 10.14 to Registration statement on
       Form S-4 (No. 333-05557) filed June 7, 1996)

10.21  Amendment to Office Space Lease Agreement (Exhibit 10.14 to Registration
       statement on Form S-4 (No. 333-05557) filed June 7, 1996)

10.22  Office Space Lease Agreement for GlobalSCAPE (Exhibit 10.29 to
       Registration statement on Form S-4 (No. 333-47511) filed on March 6,
       1998)

10.23  Commercial Lease with ACLP University Park SA, L.P. (Exhibit to this
        Amended Annual Report on Form 10-K for year ended July 31, 1999 filed
        April 14, 2000)

10.24  Amendment to Commercial Lease with ACLP University Park SA, L.P. (Exhibit
       to this Amended Annual Report on Form 10-K for year ended July 31, 1999
       filed April 14, 2000)

10.25  Commercial Lease between GlobalSCAPE, Inc. and ACLP University Park SA,
       L.P (Exhibit to this Amended Annual Report on Form 10-K for year ended
       July 31, 1999 filed April 14, 2000)

10.26  Amendment to Commercial Lease between GlobalSCAPE, Inc. and ACLP
       University Park SA, L.P (Exhibit to this Amended Annual Report on Form
       10-K for year ended July 31, 1999 filed April 14, 2000)

10.27  Compensation Agreement between ATSI-Texas and James relating to Guarantee
       of Equipment Line of Credit by James McCourt (Exhibit 10.3 to
       Registration statement on Form 10 (No. 000-23007) filed on August 22,
       1997)

10.28  Consulting Agreement with KAWA Consultores, S.A. de C.V. (Exhibit to this
       Amended Annual Report on Form 10-K for year ended July 31, 1999 filed
       April 14, 2000)

11     Statement of Computation of Per Share Earnings (Exhibit 11 to Annual
       Report on Form 10-K for year ended July 31, 1999 filed October 26, 1999)

22     Subsidiaries of ATSI (Exhibit 22 to Annual Report on Form 10-K for year
       ended July 31, 1999 filed October 26, 1999)

23     Consent of Arthur Andersen LLP) (Exhibit to this Amended Annual Report on
       Form 10-K for year ended July 31, 1999 filed August 25, 2000)

27     Financial Data Schedule (Exhibit 27 to Annual Report on Form 10-K for
       year ended July 31, 1999 filed October 26, 1999)

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99.1   ATSI Shareholder Newsletter (Exhibit 99.1 to Annual Report on Form 10-K
       for year ended July 31, 1999(File No. 000-23007) filed October 26, 1999)

99.2   FCC Radio Station Authorization - C Band (Exhibit 10.10 to Registration
       statement on Form S-4 (No. 333-05557) filed June 7, 1996)

99.3   FCC Radio Station Authorization - Ku Band (Exhibit 10.11 to Registration
       statement on Form 10 (No. 333-05557) filed June 7, 1996)

99.4   Section 214 Certification from FCC (Exhibit 10.12 to Registration
       statement on Form 10 (No. 333-05557) filed June 7, 1996)

99.5   Comercializadora License (Payphone License) issued to ATSI-Mexico
       (Exhibit 10.24 to Registration statement on Form 10 (No. 000-23007) filed
       August 22, 1997)

99.6   Network Resale License issued to ATSI-Mexico (Exhibit 10.25 to
       Registration statement on Form 10 (No. 000-23007) filed August 22,
       1997)

99.7   Shared Teleport License issued to Sinfra (Exhibit to this Amended Annual
       Report on Form 10-K for year ended July 31, 1999 filed April 14,
       2000)

99.8   Packet Switching Network License issued to SINFRA (Exhibit 10.26 to
       Registration statement on Form 10 (No. 000-23007) filed August 22, 1997)

99.9   Value-Added Service License issued to SINFRA(Exhibit to this Amended
       Annual Report on Form 10-K for year ended July 14, 1999 filed April 13,
       2000)

99.10  Potential Dilution Chart (Exhibit to this Amended Annual Report on Form
       10-K for year ended July 31, 1999 filed April 14, 2000)

99.11  Preferred Stock Features (Exhibit to this Amended Annual Report on Form
       10-K for year ended July 31, 1999 filed April 14, 2000)

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                                  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 authorized, in San Antonio, Texas on
September 8, 2000.

                    AMERICAN TELESOURCE INTERNATIONAL, INC.


                        By: /s/ Arthur L. Smith
                            -------------------
                            Arthur L. Smith
                            Chief Executive Officer


                        By: /s/ H. Douglas Saathoff
                            -------------------------
                            H. Douglas Saathoff
                            Senior Vice President, Chief Financial Officer and
                            Corporate Secretary


Pursuant to the requirements of Section 13 or 15(d) of the Securities Act of
1934, this report has been signed below by the following persons in the
capacities indicated on April 13, 2000.

          Signature                                     Title
          ---------                                     -----

     /s/ ARTHUR L. SMITH                   Chairman of the Board, Chief
     -------------------                   Executive Officer, Director
                                           (Principal Executive Officer)

     /s/ H. DOUGLAS SAATHOFF               Chief Financial Officer, Senior Vice
     -----------------------               President, and Corporate Secretary
                                           (Principal Accounting and Finance
                                           Officer)

     /s/ RICHARD C. BENKENDORF                    Director
     -------------------------

     /s/ CARLOS K. KAUACHI                        Director
     ---------------------

     /s/ MURRAY R. NYE                            Director
     -----------------

     /s/ TOMAS REVESZ                             Director
     ----------------

     /s/ ROBERT B. WERNER                         Director
     --------------------

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