<PAGE>

                                                                   EXHIBIT 10.15

                            AGREEMENT OF EMPLOYMENT

     THIS EMPLOYMENT AGREEMENT ("Agreement"), as of December 20, 1999
("Effective Date") by and among INDEPENDENT WIRELESS ONE CORPORATION, a Delaware
Corporation ("IWO"), IWO Holdings Inc., a Delaware Corporation ("Holdings" and
together with IWO the "Corporation") and JOHN HART, JR., residing at 2593 Route
21, Mile Hill Road, Valatie, New York 12184, hereinafter called the
("Employee").

                                   RECITALS
                                   --------

     WHEREAS, the Corporation desires to induce and secure the employment of the
Employee as Chief Technical Officer and Employee desires to be so employed by
the Corporation,

                                  AGREEMENTS
                                  ----------

     1.   Employment and Term.  Subject to the provisions for earlier
          -------------------
termination and extension as hereinafter provided in Paragraph 7 below, the
Corporation hereby employs the Employee and the Employee agrees to serve the
Corporation for a term of three (3) years commencing upon the Effective Date and
extending until December 31, 2002.

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

          (a)  The Employee shall serve as Chief Technical 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 and not inconsistent therewith as may be assigned to him by the
Chief Executive Officer of the Corporation.

          (b)  So long as this Agreement shall continue in effect, the Employee
shall devote substantially his full business time and energies to the business
and affairs of the Corporation, and to any subsidiary or affiliate of the
Corporation as directed by the Corporation, and use his best efforts, skills and
abilities to promote its interests.

     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: one hundred seventy five thousand dollars ($175,000) per annum from the date
hereof through June 30, 2000; one hundred seventy seven thousand five hundred
dollars ($177,500) per annum from July 1, 2000 through June 30, 2001; one
hundred eighty thousand dollars ($180,000) per annum from July 1, 2001 to June
30, 2002; and one hundred eighty five thousand dollars ($185,000) per annum from
July 1, 2002 to December 31, 2002. The foregoing basic salary shall be paid in
such regular installments
<PAGE>

                                      -2-

as are applied generally to salary period payments to other employees of the
Corporation, but in no event less than twice monthly.

          (b)  Cash Bonus Compensation. As an added inducement for the Employee
               -----------------------
to use his best efforts to enhance the business of the Corporation, the
Corporation shall pay to the Employee, as additional compensation hereunder, an
annual cash bonus in the following amount and subject to the following terms and
conditions:

               (i)   for and in respect of each fiscal year (or partial fiscal
                     year) of the Corporation during the term of Employee's
                     employment by the Corporation whether or not such
                     employment is under this Agreement or any extension hereof,
                     commencing with the portion of the fiscal year beginning
                     January 1, 2000, which succeeds the effective date hereof,
                     amounts, payable as provided below, equal to up to 100% of
                     the basic compensation ("Annual Bonus") described in
                     subparagraph (a) above. Such bonus shall be payable pro
                     rata to Employee to the extent, and only to the extent,
                     that business plan targets (including by way of example
                     only, such targets as Earnings Before Interest, Taxes,
                     Depreciation and Amortization ("EBITDA"), revenue, and/or
                     target service levels) and individual management
                     performance targets (as both such business plan and
                     individual performance targets have been developed by the
                     Corporation's Chief Executive Officer and Board of
                     Directors in consultation with Employee and issued within
                     forty-five (45) days after the commencement of the relevant
                     fiscal year of the Corporation (or portion thereof) have
                     been exceeded or met by at least 75% of target with respect
                     to the relevant fiscal year (or portion of the relevant
                     fiscal year) of the Corporation and not to exceed 100% of
                     the Annual Bonus; and

               (ii)  for any partial fiscal year of the Corporation during which
                     Employee is employed by the Corporation and in respect of
                     which cash bonuses are payable to Employee hereunder, the
                     amount of such bonuses payable to Employee (and
                     calculations of business plan target achievement and
                     individual performance, as the case may require) shall be
                     appropriately prorated for such portion of such partial
                     fiscal year as shall fall within the operation of this
                     provision; and

               (iii) On the date hereof, Employee shall be paid a bonus for the
                     year ending December 31, 1999 in the amount of one hundred
                     seventy five thousand dollars ($175,000.00).
<PAGE>

                                      -3-

Employee must be employed full-time on the last day of the applicable period for
which the cash bonus is paid to receive the bonus except as set forth in
3(b)(iii) above.

          (c)  Other Emoluments and Benefits.  The Employee shall be entitled to
               -----------------------------
participate in all rights and benefits for which he shall be eligible under any
stock option plan, bonus, participation or extra compensation plans, pensions,
dental, vision, life, and disability group insurance or other benefits which the
Corporation  may provide for its executive employees generally from time to time
during the term of this Agreement, provided further that commencing the
Effective Date and until formal Corporation plans are in place, suitable
temporary arrangements shall be made for the Employee, including but not limited
to paying current COBRA payments on his behalf.  Employee shall also be entitled
to a computer and appropriate peripherals, a wireless telephone (tolls and
charges paid), leased vehicle for business use, an allowance of three hundred
dollars ($300.00) per month during the period prior to availability of such
leased vehicle to defray the costs of the use of an automobile for business
purposes.

          (d)  Vacation. Employee shall be entitled annually to 248 hours of
               --------
time-off from the Employee Paid Time Off Pool as such computation is customarily
administered by the Corporation. Time-off or vacation time not used during the
calendar year or partial calendar year in which earned may be carried forward to
subsequent calendar years or partial calendar years ("Carry Forward Time").
However, Employee may not carry over more than 40 hours of Carry Forward Time in
any one year and may not aggregate more than 160 hours of Carry Forward Time in
total.

          (e)  Stock Incentive Plan. In addition to the basic compensation and
               --------------------
cash bonus compensation provided herein, Employee shall be entitled during the
term of his employment to participate in the Management Stock Incentive Plan of
the Corporation, dated as of the date hereof, and pursuant thereto has been
granted certain options pursuant to a Stock Option Agreement entered into
between the Employee and the Corporation as of the date hereof. Such Agreement
is incorporated herein by reference as Exhibit A.
                                       ---------

     4.   Expenses.  The Corporation shall provide Employee with a Corporate
          --------
credit card, and further shall pay or reimburse the Employee for all reasonable
traveling and other expenses incurred or paid by the Employee in connection with
the performance of his services under this Agreement upon presentation of
expense statements or vouchers and any such other supporting information in such
form as the Corporation may from time to time request; provided, however, that
the amount available for such traveling and other expenses shall be consistent
with general corporate policy guidelines established by the Corporation.

     5.   Payment.  Expenses, benefits and allowances due Employee hereunder
          -------
shall be paid not later than thirty (30) days following Employee's entitlement
to same, which, in the case of expenses, shall commence with the Employee's
request for reimbursement.  Employee bonuses shall be paid within forty-five
(45) days following year end.
<PAGE>

                                      -4-

     6.   Restrictive Covenants.  In consideration of payment to Employee of the
          ---------------------
compensation specified in Paragraph 3 above, Employee hereby covenants and
agrees as follows:

          (a)  Employee shall treat either as trade secrets or as confidential
or as proprietary information of the Corporation (i) any data or information
acquired during the course of or as a result of his employment, which is not
otherwise available to Employee except by reason of his employment, including
but not limited to such items as reports or findings from tests, investigative
studies, consultations or the like, methodology, proposals, systems, programs or
marketing techniques, and strategies developed by but not generally released by
the Corporation or peculiar to the business of any customer or client of the
Corporation and all particularized information relating thereto; (ii) names or
lists of the Corporation's clients or information, data or services made
available to such clients not made public by the Corporation and non-public
information relating to the operating methods or plans or requirements of any
customer or client of the Corporation; and (iii) any other data or information
designated either by the Corporation or by any of its customers or clients as
confidential or proprietary.

          (b)  All improvements, discoveries, programs, process, innovations,
and inventions, and inventions conceived (whether or not deemed patentable),
devised, made, developed or perfected by Employee during any period of his
employment by the Corporation or any period prior to the effective date hereof
during which Employee was in the service of any entity acquired by the
Corporation or any period prior to the effective date hereof during which
Employee was in the service of any entity acquired by the Corporation and
related in any material way to the business, including development and research
of the Corporation, shall be fully and promptly disclosed to the Corporation and
the same shall be the sole and absolute property of the Corporation. Upon
request of the Corporation, the Employee will execute all documents reasonably
deemed appropriate by the Corporation to secure the foregoing rights and for
obtaining the grants of patents, both domestic and foreign, with respect to such
improvements, discoveries, programs, processes, innovations or inventions and
for vesting title to such patents in the Corporation provided, however, that
Employee shall not be required to incur any costs or legal expenses in
conjunction with the compliance of any such request.

          (c)  Employee agrees to refrain, except as properly required in the
business of the Corporation, or as authorized in writing by the Corporation, (i)
from using for Employee's own benefit any matters to be treated as trade secrets
or as confidential or proprietary information under Paragraph (a) above; (ii)
from using these matters for the benefit of any other person, firm or
corporation; (iii) from disclosing these matters to any other person, firm or
corporation; and (iv) from authorizing or permitting such disclosure during the
term of his employment or thereafter.

          (d)  Employee agrees to surrender to the Corporation at any time upon
request and in any event upon termination of employment, except as the
Corporation may otherwise consent in writing, all written documents, sketches,
records or information whether copyrighted or patented or not, or any copies of
imitations thereof, whether made by Employee or not, which embody or contain or
describe in any way those matters to be
<PAGE>

                                      -5-

treated as trade secrets or as confidential or proprietary information under
Paragraph (a) above. The Corporation shall not unreasonably withhold
authorization for Employee to retain any matters covered by this Paragraph 6,
the continued possession of which by Employee will not, in the Corporation's
sole but reasonable, opinion, be detrimental to the best interest of the
Corporation.

          (e)  Employee agrees, during the term of his employment and for a
period of two (2) years after the termination thereof, whether such termination
be voluntary or not, that the Employee will not, except at the direction of the
Corporation, either directly or indirectly, for himself as a proprietor,
principal partner, director, officer, employee, agent or other representative
acquire or attempt to acquire the business then conducted by the Corporation
with any customer of the Corporation under any contracts existing or proposals
submitted on or before the date of termination of his employment.

               The term "Customer of the Corporation" for purposes hereof shall
mean any individual or entity which is the ultimate user or recipient of the
Corporation's (or any subsidiary of the Corporation) services and products
whether the same be made available directly to such entity or through an
intermediate purchaser of such services and products.

          (f)  Employee agrees to refrain, during the term of his employment and
for one (1) year thereafter, from hiring or offering to hire, except with the
written permission of the Corporation, any employee of the Corporation or from
enticing away or in any other manner persuading or attempting to persuade any
employee of the Corporation to discontinue his relationship with the
Corporation, provided, however, that nothing herein shall prohibit Employee from
hiring or offering to hire, any employee of the Corporation where the initial
hiring inquiry was solely initiated by any such employee or a third party
without the direction from Employee.

          (g)  No provision of this paragraph 6 is intended to limit Employee's
right to use or disclose information which is in the public domain or a matter
of common knowledge, or which is generally known in the industry, or acquired by
him from a third party not prohibited from making such disclosure to him, or
which information was already known to Employee other than by breach of this
Agreement; nor is it intended to limit the Employee's obligation to comply with
lawful subpoenas or other lawful process.

          (h)  No act or failure to act shall be a waiver of any right conveyed
hereunder, except an express waiver in writing. The rights reserved to the
Corporation under this Paragraph 6 of this Agreement are necessarily of a
special, unique, unusual and extraordinary character, which gives them a
peculiar value, the loss of which cannot reasonably or adequately be compensated
for in damages in an action at law, and the breach by Employee of any of the
provisions in this Paragraph 6 will cause the Corporation irreparable injury.
Therefore, in addition to any other available remedies, the Corporation shall be
entitled to an injunction to restrain any violation of this Agreement by
Employee, his agents, servants or employees and all persons, firms, or
corporations acting for or with him. The obligations of the Employee under the
<PAGE>

                                      -6-

covenants herein contained shall not cease upon termination of his employment
for whatever reason, except where otherwise limited in time above.

               These covenants contained in this Paragraph 6 on the part of the
Employee shall each be construed as an agreement independent of any other
provision in this Agreement, and the existence of any claim or cause of action
of Employee against the Corporation, whether predicated on this Agreement or
otherwise, shall not constitute a defense to the enforcement by the Corporation
of such covenants.  It is the intention of both parties to make the covenants of
this Paragraph 6 binding only to the extent that it may be lawfully done under
existing applicable laws.  In the event that any part of any covenant of this
Paragraph 6 is determined by a court of law to be overly broad thereby making
the covenant unenforceable, the parties hereto agree, and it is their desire,
that such court shall substitute a reasonable judicially enforceable limitation
in place of the offensive part of the covenant, and that as so modified the
covenant shall be as fully enforceable as set forth herein by the parties
themselves in the modified form.

     7.   Terms and Earlier Termination.
          -----------------------------

          (a)  Subject to the provisions for earlier termination as herein
provided, the term of this Agreement shall commence and terminate as specified
above.

          (b)  This Agreement shall terminate prior to the expiration date
hereinafter set forth in the event that the Board of Directors shall determine
that the Employee has become disabled, or the Employee shall be dismissed for
cause, as hereinafter provided:

               (i)  The Board of Directors of the Corporation may determine that
                    the Employee has become disabled, for purposes of this
                    Agreement, in the event that the Employee shall fail,
                    because of illness or incapacity, to render for sixty (60)
                    successive days in excess of the number of days provided for
                    in the Corporation's then applicable sick leave policy or
                    for shorter periods aggregating ninety (90) days or more in
                    excess of the number of days provided for in the
                    Corporation's then applicable sick leave policy during the
                    term hereof, services of the character contemplated by this
                    Agreement, and thereupon this Agreement and the employment
                    of the Employee hereunder shall be deemed to have been
                    terminated as of the end of the calendar month in which such
                    determination was made.  Any termination under this
                    Paragraph 7(b)(i) shall not be deemed to be a termination
                    "for cause" for any purpose under the Agreement or under any
                    other contract or arrangement between the Employee and the
                    Corporation relating to employment services or compensation
                    between them.
<PAGE>

                                      -7-

               (ii)  The Board of Directors may dismiss the Employee for cause
                     in the event that it determines that the Employee has
                     committed: (A) fraud or material dishonesty; (B)
                     intentional or willful or grossly negligent injury to the
                     Corporation; (C) criminal conduct in relation to his
                     employment; or (D) continued neglect of his duties
                     hereunder which continues subsequent to fifteen (15) days
                     written notice to cure, provided that if a longer cure
                     period is required Employee shall diligently pursue such
                     cure; and thereupon, this Agreement shall terminate and the
                     Employee shall be removed from all positions held by him
                     with the Corporation and any subsidiary corporation,
                     effective upon the delivery of notice to the Employee by
                     the Board of Directors that it has made such determination;
                     any other termination by the Corporation shall be
                     considered termination without cause for purposes of this
                     Agreement and any other contract or arrangement between the
                     parties hereto. In the event that the Board of Directors
                     shall desire to dismiss the Employee based on any
                     determination referred to in the preceding sentence, such
                     determination shall be effective only upon the following
                     conditions complied with in the following order: (A)
                     Employee shall be furnished with a written statement
                     specifying in reasonable detail the actions or events
                     supporting such determination; (B) at the request of the
                     Employee, there shall be convened a Special Meeting of the
                     Board of Directors no later than fifteen (15) business days
                     after Employee's receipt of the notice referred to in (A)
                     above at which meeting the Employee may, with assistance of
                     counsel or other representation, present evidence to refute
                     or in mitigation of such actions or events or to establish
                     that the actions or events have been cured; and (C) within
                     five (5) business days after the adjournment of such
                     Special Meeting, the Board of Directors shall furnish a
                     written statement to Employee that, based upon Employee's
                     representations and upon other relevant evidence, such
                     determination has either been confirmed or rescinded.

               (iii) The Board of Directors may terminate this Agreement and
                     dismiss the Employee, without cause and for any reason
                     deemed sufficient by the Board of Directors. In the event
                     that the Board of Directors shall decide to dismiss the
                     Employee and terminate this Agreement based on any
                     determination referred to in the preceding sentence, such
                     determination shall be effective as of such date as shall
                     be designated by notice in writing from the Board of
                     Directors
<PAGE>

                                      -8-

                     to the Employee (the "Effective Termination Date"). In the
                     event that this Agreement is terminated pursuant to this
                     subparagraph (iii), Employee shall be entitled to payment
                     on the Effective Termination Date of an amount equal to (A)
                     the lesser of the basic salary due pursuant to paragraph
                     3(a) to accrue during the remainder of the initial three-
                     year term of this Agreement or the basic salary that would
                     be due under paragraph 3(a) for the twelve (12) month
                     period following the Effective Termination Date; plus (B)
                     such cash bonus compensation prorated to the Effective
                     Termination Date otherwise due Employee pursuant to
                     paragraph 3(b); and (C) the benefits to be paid to Employee
                     pursuant to paragraph 3(c), 3(d) and 3(e) prorated to the
                     Effective Termination Date.

          (c)  Notwithstanding anything to the contrary contained herein, any
termination of Employee's employment by the Corporation pursuant to the terms of
this paragraph, shall not affect or diminish:  (i) any rights accruing to the
Employee under this Agreement prior to the effective date of such termination
and in such event Employee rights to all compensation, including, but not
limited to, Paragraphs 3 and 4 above, shall be calculated and paid for and in
respect of any period prior to such effective date; and (ii) any rights or
remedies available to the Corporation by reason of any breach or threatened
breach of the provisions of Paragraph 7 hereof, the force and effect of which
provisions shall survive the termination of this Agreement, however such
termination occurs.

          (d)  In the event Employee gives his notice to terminate prior to the
expiration of the Initial Term, Employee shall be entitled to any rights
accruing to the Employee under this Agreement prior to the effective date of
termination and in such event Employee rights to all compensation shall be
calculated and paid for to such effective date, including but not limited to,
his basic salary as described in 3(a), his emoluments and benefits as described
in paragraph 3(c), any unused vacation as set forth in paragraph 3(d), and any
incurred or paid expenses as set forth in paragraph 4.  Additionally, Employee
shall be entitled to any vested Stock Incentive Payments as described in
paragraph 3(e).

     8.   Partial Invalidity.  All paragraphs, subparagraphs, and portions of
          ------------------
this Agreement shall be considered as separate and distinct from one another,
and if, for any reason any paragraph, subparagraph or portion of this Agreement
shall be held to be invalid or unenforceable, it is agreed that the same shall
not be held to affect the validity or enforceability of the remaining
paragraphs, subparagraphs or portions of this Agreement.

     9.   Notice.  Any notices, requests, demands or other communications
          ------
required or permitted under this Agreement shall be in writing and shall be
deemed to have been given when delivered personally, one (1) day after being
sent by recognized overnight courier service with all charges prepaid or charges
to the sender's account, or three (3)
<PAGE>

                                      -9-

days after being mailed by certified mail, return receipt requested, addressed
to the party being notified at the address of such party first set above, or at
such other address as such party may hereafter have designated by notice;
provided, however, that any notice of change of address shall not be effective
until its receipt by the party to be charged therewith. Copies of any notices or
other communications to the Corporation shall simultaneously be sent by first
class mail to:

          Independent Wireless One Corporation
          c/o Hage and Hobaica LLP
          610 Charlotte Street
          Utica, New York 13501-2909

     Notice to Holdings shall be as follows:

          c/o Investcorp International Inc.
          280 Park Avenue
          New York, New York 10017
          Telephone: 212-599-4700
          Facsimile: 212-983-7073
          Attention: Christopher J. Stadler

          With a copy to:

          Gibson, Dunn & Crutcher LLP
          200 Park Avenue
          New York, New York 10166
          Telephone: 212-351-4000
          Facsimile: 212-351-4035
          Attention: Sean P. Griffiths, Esq.

     10.  Corporation Defined. The terms "Independent Wireless One Corporation"
          -------------------
and "IWO Holdings, Inc." as used in this Agreement, shall include, respectively,
IWO and Holdings, and its respective successors and/or assigns, any subsidiary
corporation of IWO and Holdings, and any corporation into which or which IWO or
Holdings may be merged or consolidated or to which all, or substantially all, of
their respective businesses and/or assets are transferred.

     11.  Waiver of Breach.  The waiver by either party of a breach of any
          ----------------
provision of this Agreement, shall not operate or be construed as a waiver of
any subsequent breach by the same party.

     12.  Integration:  Entire Agreement.  This instrument contains the entire
          ------------------------------
agreement of the parties with regard to the subject matter hereof and supersedes
all prior oral or written understandings, memoranda or communications with
regard to the terms or conditions of Employee's employment by the Corporation.
All other forms of this agreement, including , but not limited to, the Agreement
of Employment between IWO and Employee Dated as of June 7, 1999 are hereby
declared superseded and void.  This Agreement may not be changed orally, but
only by an agreement in writing signed by the
<PAGE>

                                      -10-

party against whom enforcement of any waiver, change, modification, extension or
discharge is sought.

     13.  Binding Effect.  Except as otherwise provided hereinabove, this
          --------------
contract shall inure to the benefit of, and be binding upon, the heirs,
executors, administrators, successors and assigns of the parties hereto.

     14.  Assignment.  Corporation may assign all or any portion of
          ----------
Corporation's rights or delegate all or any portion of Corporation's duties
under this Agreement to any Affiliate or to any entity that acquires all or a
substantial portion of the business of the Corporation and Affiliates.  However,
any such assignment or delegation shall not relieve Corporation of its financial
obligations to Employee under this Agreement.  Except in conjunction with his
estate planning or in the event of death, Employee may not assign any rights
under this Agreement or delegate any duties under this Agreement.

     15.  Counterparts.  This Agreement may be executed in counterparts,
          ------------
including facsimile counterparts, all of which taken together shall constitute
but one agreement.
<PAGE>

                                      -11-

     IN WITNESS WHEREOF, IWO and Holdings have caused this Agreement 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 CORPORATION


BY: /s/ Solon L. Kandel
   -------------------------------------------
  Name:  Solon L. Kandel
       ---------------------------------------
  Title: President and Chief Executive Officer
        --------------------------------------

IWO HOLDINGS, INC.


BY: /s/ Solon L. Kandel
   -------------------------------------------
  Name: Solon L. Kandel
       ---------------------------------------
  Title: President and Chief Executive Officer
         -------------------------------------


EMPLOYEE

/s/ John Hart Jr.
----------------------------------------------
John Hart, Jr.
<PAGE>

                                   AMENDMENT
                                      TO
                            AGREEMENT OF EMPLOYMENT

     This is amendment to agreement of employment ("Amendment") is intended to
modify the Agreement of Employment executed on December 20, 1999 between
INDEPENDENT WIRELESS ONE CORPORATION, a Delaware Corporation ("IWO"), IWO
Holdings, Inc., a Delaware Corporation ("Holdings" and together with IWO the
"Corporation") and JOHN HART, JR., residing at 2593 Route 21 Mile Hill Road,
Valatie, New York 12184, hereinafter called the ("Employee").

                                    RECITAL

     WHEREAS, the parties desire to amend the Agreement of Employment effective
December 20, 1999.

Section 3(a) of the Agreement is replaced in its entirety as follows:

     Section 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 May 1, 2000
                          through December 31, 2000; two hundred five thousand
                          dollars ($205,000) per annum from January 1, 2001
                          through December 31, 2001; and two hundred ten
                          thousand dollars ($210,000) 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.

     Add to Section 3 as Paragraph (f)

          Relocation Expenses:  In accordance with Internal Revenue Service
          --------------------
          Regulations, any amount paid to or on behalf of you (the employee) as
          reimbursement for relocation expenses, with the exception of shipping
          household goods and travel to the new location, etc. must be included
          in your gross wages as income and will be subject to appropriate
          Federal withholding requirements.

          In such cases the Company will gross up your taxable relocation
          reimbursement amount by using federal tax rates reflective of your
          annual base salary without regard to other income.

          The gross up will be paid in cash at some date certain.
<PAGE>

All other provisions of the Agreement of Employment not amended hereby will
remain in full force and effect.



May 2, 2000                   INDEPENDENT WIRELESS ONE CORPORATION


                              BY: /s/ Solon L. Kandel
                                 -----------------------------------------
                                    Name:  Solon L. Kandel
                                    Title: President & CEO


May 2, 2000                   IWO Holdings, Inc.


                              BY: /s/ Solon L. Kandel
                                 -----------------------------------------
                                    Name:  Solon L. Kandel
                                    Title: President & CEO


May 2, 2000                   EMPLOYEE

                              /s/ John Hart, Jr.
                              --------------------------------------------
                              John Hart, Jr.