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                                                                   EXHIBIT 10.17




[Executive's Address]



Dear Bob:



     The purpose of this letter is to specify the terms of a special performance
bonus up to an amount of one million, five hundred thousand dollars ($1,500,000)
(the "Performance Bonus") that the Senior Executive Compensation Committee of
the Global TeleSystems, Inc. ("Company") Board of Directors has agreed to award
to you in the percentages set forth below upon the occurrence of certain events
itemized below (separately, the "Triggering Events" and, collectively, the
"Restructuring"). This letter agreement, when countersigned by you, amends and
augments the terms of the Employment Agreement between you and the Company (or
its affiliate) dated and effective November 1, 2000 (the "Agreement").
Specifically, but not exclusively, the Performance Bonus described herein is in
addition to, not in lieu of, the Bonus for which you are eligible under the
terms of Section 5(b) of the Agreement.



     In return for your performance of your obligations under the Agreement in
connection with the Restructuring, the Company will pay you in cash the
following percentages of the total Performance Bonus upon the occurrence of the
following events:



          1. Fifteen percent (15%) of the total Performance Bonus will be paid
     to you upon the consummation of the sales of some or all of the Company's
     interest in (i) the Central European subsidiaries of the Company, or
     businesses or assets owned by such subsidiaries (including GTS Hungaro,
     Inc., GTS Hungary Holding, Inc., GTS Poland, Inc., GTS Czech, Inc., GTS
     Romania, Inc. and GTS Slovakia s.r.o.), or (ii) Golden Telecom, Inc., which
     sales in the aggregate provide cash or other consideration to the Company
     or its affiliates with a fair market value of at least one hundred fifty
     million dollars ($150,000,000).



          2. Twenty percent (20%) of the total Performance Bonus will be paid to
     you upon the Company's or its affiliates obtaining at least $550 million of
     funding from one or more of: (i) the reaffirmation, modification or
     replacement of that certain Loan Agreement entered into by Global
     TeleSystems Holdings B.V. dated July 14, 2000 (the "Facility"), reflecting
     the consequences of the Restructuring and the revised Ebone business plan;
     (ii) new equity financing on terms acceptable to the Board; or (iii) the
     proceeds of asset sales described (in "1") above to the extent that sale
     proceeds exceed $150 million;



          3. Twenty percent (20%) of the total performance Bonus will be paid to
     you upon completion of (i) the currently-ongoing discussions with the
     holders of the publicly-traded bonds issued by Global TeleSystems (Europe),
     Ltd. ("Esprit") and the execution of a definitive agreement between Esprit
     and such Bondholders whereby the Bondholders either waive any then-existing
     defaults under such bonds or exchange such bonds for controlling equity in
     Esprit; and (ii) the sale or winding up on terms acceptable to the Board of
     all or substantially all of the companies and businesses currently
     constituting the Company's Business Services Division.



          4. Forty-five percent (45%), or the remainder, of the total
     Performance Bonus will be paid to you upon the completion of the last of
     "1", "2" and "3" above to be completed.



     The above-itemized payments will be paid to you only if you remain employed
by the Company or its affiliates at the time such payments are due under the
terms hereof; provided that the Company will pay you the above-itemized payments
on their due dates as set forth herein if you have been terminated by the
Company without Cause prior to that time. The Company's obligation to make the
payments set forth above shall expire and be of no further effect on December
31, 2001 as to those Triggering Events that have not been substantially
completed by that time, and shall expire and be of no further effect on March
31, 2002 as to those Triggering Events that have not been completed fully by
that time.

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     If you agree to the terms set forth herein, please signify your agreement
by signing in the space provided below. Upon your counter-signing this
agreement, it will become the binding obligation of the Company.



                                            Sincerely,



                                            By:      /s/

                                              ----------------------------------




                                                 For Global TeleSystems, Inc.



Agreed:



By:   /s/ ROBERT J. AMMAN

    --------------------------------

         Robert J. Amman