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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                         ______________________________

                                  FORM 10-K/A
                               (AMENDMENT NO. 2)

[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934

[_]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM________ TO_________

FOR THE YEAR ENDED DECEMBER 31, 1999           COMMISSION FILE NUMBER 000-21091
                              ___________________

                          ADVANCED RADIO TELECOM CORP.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

           DELAWARE                                             52-1869023
(STATE OR OTHER JURISDICTION                                 (I.R.S. EMPLOYER
OF INCORPORATION OR ORGANIZATION)                           IDENTIFICATION NO.)

         500 108TH AVENUE, NE
            SUITE 2600
        BELLEVUE, WASHINGTON                                     98004
(ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)                      (ZIP CODE)

                                 (425) 688-8700
              (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE)
                                  _____________

          Securities registered pursuant to Section 12(b) of the Act:

                                               NAME OF EACH EXCHANGE
 TITLE OF EACH CLASS                            ON WHICH REGISTERED
---------------------                          ---------------------
       None                                            None

          Securities registered pursuant to Section 12(g) of the Act:

TITLE OF EACH CLASS:                    COMMON STOCK ($.001 PAR VALUE)
----------------------

  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, 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 aggregate market value of the registrant's voting stock held by non-
affiliates was approximately $1,274,000,000 on March 21, 2000, based on the
closing sales price of the registrant's common stock ("Common Stock") as
reported on the Nasdaq National Market as of such date.

  The number of shares outstanding of each of the registrant's classes of Common
Stock as of March 21, 2000 was as follows:  Common Stock, $.001 par value:
28,837,430



                      DOCUMENTS INCORPORATED BY REFERENCE

  None.

================================================================================

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                                    PART III

ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT.

     The following persons are directors of the Company:

NAME                     AGE      POSITION
----                     ---      --------

Bandel Carano..........   38      Director
Andrew I. Fillat.......   51      Director
Richard T. Liebhaber...   64      Director
Robert S. McCambridge..   41      Director
James B. Murray, Jr....   52      Director
Alan Z. Senter.........   57      Director
Marc B. Weisberg.......   42      Director


     Bandel Carano has been a director of the Company since 1999.   He has been
with Oak Investment Partners, of which he is a general partner, since 1985.  He
also serves as a director of the Investment Advisory Board for the Stanford
Engineering Venture Fund and as a director of Wireless Facilities, Inc. and
Pulsepoint Communications, Inc.

     Andrew I. Fillat has been a director of the Company since 1995.  He has
been managing director of Advent International Corporation, a global venture
capital and private equity management firm since 1995 and was vice president of
Advent from 1989 to 1995.

     Richard T. Liebhaber has been a director of the Company since 2000.  He has
been consulting managing director at Vernois, Suhler and Associates, a New York
media merchant banking firm, since 1995, and was executive vice president of MCI
Communications Corp. and a member of its management committee and board of
directors from 1985 to 1995.  He also services as a director of KPN/Qwest, AVICI
Systems, Inc., Internet Communications Corporation, Rare Medium Group, and
Alcatel USA, Inc.

     Robert S. McCambridge has been director of the Company since 2000.  He has
been President and Chief Operating Officer of ART since 1999 and was Executive
Vice President and Chief Financial Officer of ART from 1998 to 1999.  Prior to
joining ART, he was Executive Vice President and Chief Financial Officer of One
Comm, formerly Cable Plus Holding Company, from 1996 to 1998, President of the
Robert S. McCambridge Company from 1995 to 1996, and Director of Pacific
Northwest Corporate Finance of Dain Bosworth, Inc. from 1994 to 1995.

     James B. Murray, Jr. has been a director of the Company since 1997.  He has
been managing director of Columbia Capital Corporation since March 1989.  He
also serves as a director of Saville Systems PLC and The Columbia Group
Incorporated.

     Alan Z. Senter has been a director of the Company since 1996.  He has been
chairman of Senter Associates, a financial advisory firm since 1996 and from
1993 to 1994 and was  executive vice president and Chief Financial Officer of
NYNEX Corporation from 1994 to 1996.   He also serves as a director of XL Ltd.

     Marc B. Weisberg has served as a director of the Company since 1999.  He
has been the senior vice president of corporate development at Qwest
Communications International, Inc. since 1997, and prior to then was at Weisberg
& Company, an investment banking and advisor service which he founded.

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ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS.

     The following information regarding certain transactions with directors,
officers and holders of record or beneficially of more than five percent of
ART's common stock does not include information for any period during which such
person or entity, as the case may be, was not an officer, director or five
percent holder.

INVESTMENT BY COLUMBIA CAPITAL CORPORATION AND ADVENT INTERNATIONAL CORPORATION
IN THE COMPANY

     In September 1999, the Company sold Class A and Class B convertible
preferred stock to a group of investors in exchange for $251 million. The group
of investors included investment funds affiliated with Columbia Capital
Corporation, of which James B. Murray, Jr. is a managing director, and which at
the time of the investment held greater than five percent of the Company's
outstanding common stock.  The group of investors also included funds affiliated
with Advent International Corporation, of which Andrew I. Fillat is a managing
director. As part of the investment group, each of Columbia and Advent invested
$20 million in the Company in return for 250,000 shares of preferred stock.
Under the preferred stock purchase agreement between the Company and the
investors signed in June 1999, the investors loaned the Company $50 million as a
bridge loan bearing interest at a rate of 11%, which was repaid in September
1999.

QWEST OPERATING AGREEMENTS

     In June 1999, the Company entered into a private line agreement, a co-
location license agreement, a broadband services agreement and a coordinated
marketing agreement with Qwest, which beneficially owns greater than five
percent of the Company's outstanding voting stock.  These contracts provide for,
among other things, (i) integration of the Company's broadband wireless networks
with Qwest's fiber-optic network using Qwest as the Company's exclusive provider
of fiber-optic backbone, (ii) co-location of equipment with Qwest where
desirable, and (iii) joint marketing of products with Qwest where desirable.

LOAN TO MR. HIRSCH

     In November 1997, the Company loaned Mr. Hirsch, the Company's former
Chairman of the board of directors and Chief Executive Officer, $887,500 to
purchase 100,000 shares of common stock at $8.875 per share, the fair market
value of the stock on the date of the loan.  The loan accrued interest at the
applicable federal rate, was payable in 2003, and was secured by the shares
purchased.  Mr. Hirsch repaid the debt following his resignation.

AGREEMENT WITH TRITON NETWORK SYSTEMS INC.

     In December 1999, we entered into a supply agreement with Triton Network
Systems Inc. under which we are obligated to purchase and Triton is obligated to
supply their products  under the terms and conditions described in the
agreement.  Bandel Carano, one of our directors, beneficially owns more than 10%
of Triton, as a general partner of Oak Investment Partners VII, Limited
Partnership and a related entity.  During 1999, we paid approximately $693,000
to Triton.

WIRELESS FACILITIES INC.

     Wireless Facilities Inc. provides us with network deployment services.
Bandel Carano, one of our directors, beneficially owns more than 10% of Wireless
Facilities, as a general partner of Oak Investment Partners VIII, Limited
Partnership and a related entity.  During 1999, we paid approximately $1,651,000
to Wireless Facilities.

                                      -3-
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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 duly authorized on this 19th day of May
2000.

                                    Advanced Radio Telecom Corp.

                                    R. S. McCambridge

                                    By: /s/ R. S. McCambridge
                                        ------------------------
                                        President, Chief Operating Officer and
                                        Principal Financial Officer

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