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                                                                 Exhibit 10.12.3

                                    AMENDMENT
                                       TO
                             AGREEMENT OF EMPLOYMENT

     This AMENDMENT TO AGREEMENT OF EMPLOYMENT (this "Amendment"), dated as of
November 15, 2000, is intended to modify the Agreement of Employment, dated as
of April 9, 2000 (the "Agreement of Employment"), among Independent Wireless One
Corporation, a Delaware corporation ("IWO"), IWO Holdings, Inc., a Delaware
corporation ("Holdings" and together with IWO, the "Corporation") and Steven M.
Nielsen, residing at 26 Port Huron Drive, Niskayuna, New York 12309 (the
"Employee").

                                    RECITALS

     WHEREAS, the Corporation desires to induce and secure the employment of the
Employee as President and Chief Executive Officer and Employee desires to be so
employed by the Corporation, effective as of November 15, 2000.

                                   AGREEMENTS

     NOW THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the parties hereto agree as follows:

     SECTION 1.
     ----------

     (a)  Section 2(a) of the Agreement of Employment is hereby amended and
restated in its entirety as follows:

          "2.  Duties of Employee.
               ------------------

               (a) The Employee shall serve on the Board of Directors of the
     Corporation and as President and Chief Executive Officer of the
     Corporation, and of any subsidiary or affiliated corporation if elected by
     the appropriate Board of Directors, and shall perform such duties as are
     appropriate to such office as may be assigned to him by such Board of
     Directors. Subject to the direction of the Board of Directors, the Employee
     shall be responsible for the establishment of the policies, plans and
     strategic goals of the Corporation, and shall have primary authority and
     responsibility for the direction of the day to day business of the
     Corporation, including, but not limited to its operating divisions and
     performance of work and contracts; supervision of general, administrative,
     financial, and human resources support staff; and reportee for employee
     general supervision, performance appraisals and operations functions. The
     Corporation agrees that the duties assigned to the Employee shall not be
     inconsistent therewith and that the Employee shall have such powers,
     authority and facilities at his disposal as are suitable to his position
     and as shall reasonably be required to enable him to discharge his duties
     in an efficient manner."

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     (b)  Section 3(a) of the Agreement of Employment is hereby amended and
restated in its entirety as follows:

          "3.  Compensation.
               ------------

               (a)  Basic Salary. The Corporation will pay the Employee during
                    ------------
          the term hereof for all services to be rendered hereunder a basic
          salary at the rate of two hundred thousand dollars ($200,000) per
          annum from the Effective Date through November 15, 2000; two hundred
          seventy-five thousand dollars ($275,000) per annum from November 16,
          2000 through December 31, 2001; and two hundred eighty-five thousand
          dollars ($285,000) per annum from January 1, 2002 to December 31,
          2002. The foregoing basic salary shall be paid in such regular
          installments as are applied generally to salary period payments to
          other employees of the Corporation, but in no event less than twice
          monthly."

     (c)  Section 3(b)(i) of the Agreement of Employment is hereby amended by
deleting therefrom the words "Corporation's Chief Executive Officer and."

     (d)  Section 3(d) of the Agreement of Employment is hereby amended by
deleting from the last sentence thereof the words "All time off is subject to
approval by the CEO and."

     SECTION 2.
     ----------

     (a)  Counterparts. This Amendment may be executed in two or more
          ------------
counterparts, each of which will be deemed an original but which together will
constitute one and the same instrument. Delivery of an executed counterpart of a
signature page of this Amendment by facsimile transmission shall be as effective
as delivery of a manually executed counterpart of this Amendment.

     (b)  Headings; Sections. All headings and captions in this Amendment are
          ------------------
for purposes of reference only and will not be construed to limit or affect the
substance of this Amendment. All references to Section in this Amendment refer
to Sections of this Amendment, unless otherwise expressly provided for.

     (c)  Other Provisions. All other provisions of the Agreement of Employment
          ----------------
not amended hereby will remain in full force and effect.

                            [signature page follows]

                                       2

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     IN WITNESS WHEREOF, IWO and Holdings have caused this Amendment to be
signed by their respective officers hereunto duly authorized, and the Employee
has hereunto set his hand and seal, effective as of the day and year first above
written.

INDEPENDENT WIRELESS ONE                INDEPENDENT WIRELESS ONE
CORPORATION                             CORPORATION

By:  /s/ Michael E. Cusack              By:    /s/ Alfred F. Boschulte
     --------------------------                --------------------------
     Name:  Michael E. Cusack           Name:  Alfred F. Boschulte
     Title: Vice-President              Title: Chairman
            & Secretary

IWO HOLDINGS, INC.                      IWO HOLDINGS, INC.


By:  /s/ Michael E. Cusack              By:    /s/ Alfred F. Boschulte
     --------------------------                --------------------------
     Name:  Michael E. Cusack           Name:  Alfred F. Boschulte
     Title: Vice-President              Title: Chairman
            & Secretary

                                        EMPLOYEE

                                        /s/ Steven M. Nielsen
                                        ---------------------------------
                                        Steven M. Nielsen