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                                    NEON
                               Communications



                                                                  EXHIBIT 10.59


September 17, 2001


Mr. William A. Marshall
99 Sugarcane Lane
North Andover, MA 01845

Dear Bill:

It is our pleasure to extend to you this offer of employment with NEON
Communications, Inc. ("NEON or the company"), in the capacity of Chief
Financial Officer and Treasurer. The company is enthusiastic about your
joining us, and we believe that your background and qualifications will
contribute to our future growth.

On behalf of the company, we have set forth below the terms of your
employment.

1.  You are being employed to serve full-time as Chief Financial Officer and
    Treasurer. You will report to Stephen E. Courter, Chief Executive Officer.

2.  Your responsibilities will include management and development of all
    financial aspects of the company's business.

3.  Your salary will be at an annualized rate of $210,000, payable in
    accordance with the company's normal payroll practices. You will be paid
    biweekly. You are recommended for a 35% bonus, paid annually. In the
    event NEON reinstates the 5% pay cuts, your salary will be adjusted to
    $225,000.

4.  You will be eligible to participate in the medical and dental insurance
    plans offered by NEON commencing on your first day of employment. You
    will also be eligible to participate in the company's 401(k) retirement
    plan, the company's life and disability insurance programs, as well as
    the other company benefits. Finally, you will have an opportunity to
    participate in the company's stock option program, according to company
    policy and based on performance. You will receive an initial grant of
    350,000 incentive stock options (three-year vesting) at the closing price
    on your hire date.

   NEON COMMUNICATIONS, INC.  2200 WEST PARK DRIVE  WESTBOROUGH, MA 01581
    800.891.5080 TEL  508.616.7800 TEL 508.616.7895 FAX www.NEONINC.COM

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Mr. William A. Marshall
Page 2
September 17, 2001


        IN THE EVENT THAT ANY SECURITIES, AS DEFINED BELOW, ARE ISSUED OR
        OTHERWISE COMMITTED IN CONNECTION WITH THE RESTRUCTURING, SETTLEMENT,
        MODIFICATION, CONVERSION, PAYMENT OF PRINCIPAL OR INTEREST, OR OTHER
        CHANGES TO THE COMPANY'S SENIOR NOTES, EXECUTION OF THE CONVERSION OF
        THE EXELON OR NORTHEAST NOTES, OR ANY CHANGES TO THE OBLIGATIONS TO
        NORTEL, THEN THE COMPANY WILL GRANT ADDITIONAL INCENTIVE STOCK
        OPTIONS TO YOU IN AN AMOUNT SUFFICIENT TO PREVENT ANY DILUTION TO
        YOUR INITIAL PERCENTAGE INTEREST IN THE COMPANY'S FULLY DILUTED
        SHARES THAT WOULD RESULT FROM SUCH TRANSACTIONS. THE ADDITIONAL
        OPTIONS WILL BE GRANTED UPON THE EXECUTION OF THE RELATED
        TRANSACTIONS AND THE EXERCISE PRICE PER SHARE WILL BE EQUAL TO THE
        AS-CONVERTED PRICE PER SHARE OF THE RELATED SECURITIES. THE VESTING
        PERIOD AND VESTING START DATE FOR THE ADDITIONAL OPTIONS WILL BE THE
        SAME AS YOUR INITIAL OPTION GRANT. THEREFORE, A PRO-RATA PORTION OF
        THE ADDITIONAL OPTIONS GRANTED WILL VEST ON AN ACCELERATED BASIS. FOR
        PURPOSES OF THIS CLAUSE, SECURITIES SHALL MEAN ANY EVIDENCES OF
        INDEBTEDNESS, SHARES, WARRANTS, OPTIONS OR OTHER SECURITIES OR
        INSTRUMENTS CONVERTIBLE INTO OR EXCHANGEABLE FOR THE COMPANY'S COMMON
        STOCK OR INSTRUMENTS THAT WOULD OTHERWISE AFFECT THE COMPANY'S FULLY
        DILUTED SHARES.

5.  You will be eligible for three weeks paid vacation beginning January 1,
    2002, in accordance with the company's vacation policy. For the remainder
    of 2001, you will be eligible for 80 hours of vacation. You will also be
    eligible for two days paid time off ("PTO") for the remainder of 2001. In
    January 2002, you will be eligible for 6 days of PTO.

6.  Performance reviews are completed annually. Merit increases are based on
    performance. You will be reviewed twelve months from your date of hire.
    For each forthcoming year, the company agrees that in no event shall it
    offer a compensation package that is less than the salary, bonus, and
    fringe benefits paid to or earned by you for the immediately preceding
    year.

7.  You will be required to execute a Nondisclosure Agreement as a condition
    of your employment.

8.  The company will provide you with a severance package to cover you in the
    event that NEON Communications terminates your employment without cause or
    terminates or modifies your employment for the following reasons:
    (i) constructive dismissal; or (ii) a change in control. Constructive
    dismissal or change in control are defined as events that result in a
    demotion of your title, change in responsibilities or relocation of the
    company by more than 25 miles. Without cause shall mean for any reason
    other than:

       a.  Illegal acts (other than minor traffic violations, misdemeanors,
           or other acts that do not result in criminal conviction) including
           convictions for theft or embezzlement.


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Mr. William A. Marshall
Page 3
September 17, 2001


       b.  Intentional material violation of published written policies of
           the company.

       c.  Irresponsible, unauthorized acts of a willful nature in the
           performance of duties that have a substantial financial impact on
           the company.

    The package will provide you with twelve month's base salary and bonus,
    in addition to benefit continuation from the time of your involuntary
    termination. There will be a provision for a review by the board of
    directors and a reasonable cure period before termination with cause is
    finalized. In addition, if you are terminated without cause,
    constructively dismissed or there is a change in control, all of your
    options will be fully vested.

9.  This offer of employment is not to be construed as an agreement to employ
    you for a stated term, and does not alter the company's policy of
    employment-at-will, allowing either you or the company to terminate the
    employment relationship for any reason at any time.


If you wish to accept this offer of employment set forth herein, please so
indicate by signing this letter in the space provided and returning it to the
Company. This offer will expire within seven days from the date of this
letter.


                                       Sincerely,



/s/ Jan Maley                          /s/ Stephen E. Courter
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Jan Maley                              Stephen E. Courter
Director, Human Resources              Chief Executive Officer



Accepted:


/s/ William A. Marshall
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William A. Marshall



Date:    9-18-2001
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