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                                                                   EXHIBIT 10.21




                              EMPLOYMENT AGREEMENT

                  THIS AGREEMENT, dated and effective the 22nd day of February,
1999 (the "Effective Date") is made by and between Global TeleSystems Group,
Inc., a Delaware corporation (the "Company") and Robert A. Schriesheim (the
"Executive").

                                    RECITALS:

                  A. It is the desire of the Company to assure itself of the
services of Executive by engaging Executive as its Executive Vice-President and
Chief Corporate Development Officer; and

                  B. Executive desires to commit to serve the Company on the
terms herein provided;

                  NOW, THEREFORE, in consideration of the foregoing and of the
respective covenants and agreements set forth below, the parties hereto agree as
follows:

                  1.     Certain Definitions.

                         (a)     "Annual Base Salary" shall have the meaning
          set forth in Section 5(a).

                         (b)      "Board" shall mean the Board of Directors of
          the Company.

                         (c)      "Bonus" shall have the meaning set forth in
          Section 5(b).

                         (d)      The Company shall have "Cause" to terminate
          Executive's employment hereunder upon Executive's

                                  (i) failure to follow a legal order of the
                  Board or the Chief Executive Officer of the Company, other
                  than any such failure resulting from Executive's Disability,
                  after notice and reasonable opportunity for cure,

                                  (ii) fraud, embezzlement, or any other similar
                  illegal act committed by the Executive in connection with the
                  Executive's duties as an executive of the Company or any
                  subsidiary or affiliate of the Company,

                                  (iii) conviction of any felony or crime
                  involving moral turpitude which causes or may reasonably be
                  expected to cause substantial economic injury to or
                  substantial injury to the reputation of the Company or any
                  subsidiary or affiliate of the Company, or

                                  (iv) willful or grossly negligent commission
                  of any other act or failure to act which causes or may
                  reasonably be expected (as of the time of such occurrence) to
                  cause substantial economic injury to or substantial injury to
                  the reputation of the Company or any subsidiary or affiliate
                  of the Company,





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                  including, without limitation, any material violation of the
                  Foreign Corrupt Practices Act, as described herein below.

                         (e)     "Change in Control" shall mean any of the
         following vents:

                                  (i) a report shall be filed with the
                  Securities and Exchange Commission pursuant to the Exchange
                  Act of 1934 (the "Act"), or successor law or provision,
                  disclosing that any "Person" (within the meaning of Section
                  13(d) of the Act), other than the Company or a subsidiary of
                  the Company, or an employee benefit plan sponsored by the
                  Company or a subsidiary of the Company is, or becomes the
                  beneficial owner (as such term is defined in Exchange Act Rule
                  13d-3), directly or indirectly of, 25% or more of the
                  outstanding voting stock of the Company (or securities
                  convertible into Company Stock) (calculated as provided in
                  Exchange Act Rule 13d-3(d) in the case of rights to acquire
                  Company Stock),

                                  (ii) any such "Person", other than the Company
                  or a subsidiary of the Company, or a employee benefit plan
                  sponsored by the Company or a Subsidiary of the Company, shall
                  purchase shares pursuant to a tender offer or exchange offer
                  to acquire any Company Stock (or securities convertible into
                  Company Stock) for cash, securities or any other
                  consideration, provided that after consummation of the offer,
                  the person in question is the beneficial owner (as such term
                  is defined in Exchange Act Rule 13d-3), directly or
                  indirectly, of 20% or more of the outstanding voting stock of
                  the Company (calculated as provided in Exchange Act Rule
                  13d-3(d) in the case of rights to acquire Company Stock),

                                  (iii) the stockholders of the Company shall
                  approve (A) any consolidation, share exchange or merger of the
                  Company (a "Change of Control Transaction") (1) in which the
                  stockholders of the Company immediately prior to such Change
                  of Control Transaction do not own at least a majority of the
                  voting power of the entity which survives/results from such
                  Change of Control Transaction, or (2) in which a shareholder
                  of the Company immediately before such Change of Control
                  Transaction, but who does not own a majority of the voting
                  stock of the Company immediately prior to such Change of
                  Control Transaction, owns a majority of the Company's voting
                  stock after such Change of Control Transaction; or (B) any
                  sale, lease, exchange or other transfer (in one transaction or
                  a series of related transactions) of all or substantially all
                  the assets of the Company, including stock held in subsidiary
                  corporations or interests held in subsidiary ventures, or

                                  (iv) there shall have been a change in a
                  majority of the members of the Board within a 24-month period
                  unless the election or nomination for election by the
                  Company's stockholders of each new director during such
                  24-month period was approved by the vote of two-thirds of the
                  directors then still in office who were directors at the
                  beginning of such 24-month period; or

                                  (v) the Company shall file a report with the
                  Securities and



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                  Exchange Commission on Form 8-K (or any successor thereto),
                  that a change in control of or over the Company has occurred.

                         (f)     "Closing Price" shall mean the closing price in
         United States Dollars ("$") of a share of Company Stock on the
         principal exchange on which such shares are traded on the day in
         question; if such exchange is in the United States, as reported in the
         Wall Street Journal or, if such exchange is in Europe, as reported in
         the Financial Times, with such price converted to $ utilizing the mean
         of the bid and offered prices for $ in the local currency for the day
         in question as reported in the Wall Street Journal.

                         (g)     "Code" shall mean the Internal Revenue Code of
         1986, as amended.

                         (h)     "Committee" shall mean either the Compensation
         Committee or a SubCommittee of such Committee duly appointed by the
         Board.

                         (i)     "Company" shall have the meaning set forth in
         the preamble hereto.

                         (j)     "Company Stock" shall mean the $.10 par value
         common stock of the Company.

                         (k)     "Contract Year" shall mean each twelve month
         period beginning on the Effective Date or an annual anniversary
         thereof.

                         (l)     "Date of Termination" shall mean (i) if
         Executive's employment is terminated by Executive's death, the date of
         Executive's death and (ii) if Executive's employment is terminated
         pursuant to Section 6(a)(ii)-(vi) the date specified in the Notice of
         Termination.

                         (m)     "Deemed Bonus" shall mean seventy-five percent
         (75%) of the rate of Executive's Annual Base Salary for such year.

                         (n)     "Disability" shall mean the absence of
         Executive from Executive's duties to the Company on a full-time basis
         for a total of six months during any 12-month period as a result of
         incapacity due to mental or physical illness which is determined to be
         reasonably likely to extend beyond the completion of the Term and which
         determination is made by a physician selected by the Company and
         acceptable to Executive or Executive's legal representative (such
         agreement as to acceptability not to be withheld unreasonably). A
         Disability shall not be "incurred" hereunder until, at the earliest,
         the last day of the sixth month of such absence.

                         (o)     "Executive" shall have the meaning set forth in
         the preamble hereto.

                         (p)     "Extension Term" shall have the meaning set
         forth in Section 2.



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                         (q)     "Good Reason" shall mean any of the following
         events which is not cured by the Company within 15 days after written
         notice thereof is given to the Company by Executive: (i) any failure to
         pay Executive's Base Salary or Bonus when due to Executive; (ii) any
         other material breach by the Company of any material term of this
         Agreement; or (iii) any material adverse change in Executive's job
         titles, duties, responsibilities, status, reporting responsibilities or
         perquisites granted hereunder, without Executive's consent. "Good
         Reason" shall cease to exist for an event on the 30th day following the
         later of its occurrence or Executive's knowledge thereof, unless
         Executive has given the Company notice thereof prior to such date.

                         (r)     "Grant Date" shall mean the date on which the
         Committee acts to grant to Executive the Options described herein.

                         (s)     "Initial Term" shall have the meaning set forth
         in Section 2.

                         (t)     "Notice of Termination" shall have the meaning
         set forth in Section 6(b).

                         (u)      "Options" shall have the meaning set forth in
         Section 5(c).

                         (v)      "Stock Option Plan" shall mean Fourth Amended
         and Restated 1992 Stock Option Plan of Global TeleSystems Group, Inc.
         or any successor plan.

                         (w)      "Term" shall have the meaning set forth in
         Section 2.

                  2.     Employment Term. The Company hereby employs the
Executive, and the Executive hereby accepts his employment, under the terms and
conditions hereof, for the period (the "Term") beginning on the effective date
hereof and ending upon Termination as set forth herein.

                  3.     Position and Duties. Executive shall serve as Executive
Vice-President and Chief Corporate Development Officer of the Company, reporting
to the Chief Executive Officer, with such responsibilities, duties and authority
as are customary for such role. Executive shall devote all necessary business
time and attention, and employ Executive's reasonable best efforts, toward the
fulfillment and execution of all assigned duties, and the satisfaction of
defined annual and/or longer-term performance criteria.

                  4.     Place of Performance. In connection with Executive's
employment during the Term, Executive shall be based at the Company's offices in
or near McLean, Virginia, except for necessary travel on the Company's business,
but may be reassigned during the Term hereof to another location identified as
the principal executive or operational headquarters of the Company.

                  5.     Compensation and Related Matters.

                         (a)     Annual Base Salary. During the Term, Executive
         shall receive a base salary at a rate not less than $375,000 per annum
         (the "Annual Base Salary"), less





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         standard deductions, paid in accordance with the Company's general
         payroll practices for executives, but no less frequently than monthly.
         The Annual Base Salary shall compensate Executive for any official
         position or directorship that Executive is asked to hold in the Company
         or its affiliates as a part of Executive's employment responsibilities.
         No less frequently than annually during the Term, the Committee on
         advice of the Company's Chief Executive Officer shall review the rate
         of Annual Base Salary payable to Executive, and may, in their
         discretion, increase the rate of Annual Base Salary payable hereunder;
         provided, however, that any increased rate shall thereafter be the rate
         of "Annual Base Salary" hereunder.


                         (b)     Bonus. Except as otherwise provided for herein,
          for each fiscal quarterly compensation period (or other period
          consistent with the Company's then-applicable normal employment
          practices) during which Executive is employed hereunder on the last
          day, Executive shall be eligible to receive a Bonus in an amount up to
          one-quarter (or other pro-rata portion as appropriate) of 75% of
          Executive's Base Salary pursuant to, and as set forth in, the terms of
          the GTS Senior Executive Bonus Plan as such Plan may be amended from
          time to time, plus such other bonus payments, if any, as shall be
          determined by the Compensation Committee in its sole discretion

                                  (i) Stock Options. The Company has granted to
                  Executive options (Options") to purchase 250,000 shares
                  ("Option Shares") in the Company pursuant to the terms of the
                  Stock Option Plan and an associated Stock Option Agreement.

                         (d)     Restricted Shares. The Company has granted to
         Executive, pursuant to the Company Equity Compensation Plan, 30,000
         Restricted Shares, which shall be subject to restrictions on their sale
         as set forth in an associated Restricted Shares Grant Letter.

                         (e)     Benefits. Executive shall be entitled to
         receive such benefits and to participate in such employee group benefit
         plans, including life, health and disability insurance policies, and
         financial planning services as are generally provided by the Company to
         its executives of comparable level and responsibility in accordance
         with the plans, practices and programs of the Company.

                         (f)     Expenses. The Company shall reimburse Executive
         for all reasonable and necessary expenses incurred by Executive in
         connection with the performance of Executive's duties as an employee of
         the Company. Such reimbursement is subject to the submission to the
         Company by Executive of appropriate documentation and/or vouchers in
         accordance with the customary procedures of the Company for expense
         reimbursement, as such procedures may be revised by the Company from
         time to time hereafter.

                         (g)     Vacations. Executive shall be entitled to paid
         vacation in accordance with the Company's vacation policy as in effect
         from time to time. However, in no event shall Executive be entitled to
         less than four (4) weeks vacation per Calendar Year. Executive shall
         also be entitled to paid holidays and personal days in accordance with
         the Company's practice with respect to same as in effect from time to
         time.






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                         (h)     Relocation. The Company acknowledges that you
         will retain your principal residence in Chicago until at least August
         1, 2000 and the Company will pay the expenses of required travel
         between your principal residence and the company's corporate offices in
         Virginia until that time or a later date that is mutually agreed-upon
         by the Company and the Executive. Upon relocation, you will relocate
         your principal residence to the area immediately surrounding either the
         Company's executive headquarters in Virginia or the operational
         headquarters in London, as specified by the Chief Executive Officer.
         Should your family remain in Chicago at the time of your relocation,
         the Company will provide you the use of a furnished corporate apartment
         near the relevant office. Should your family relocate with you at that
         time, or agree to relocate with you at a later time mutually agreed
         between you and the Company, the Company will pay the expense of moving
         your family and normal household goods in accordance with the normal
         relocation programs of the Company and you will receive a one-time-only
         payment equal to three times your normal monthly compensation,
         including all taxes normally due thereon. In addition, if you relocate
         pursuant to the Company's request to London, you will receive benefits
         normally made available to ex-patriate employees, including a housing
         allowance, a car allowance, tuition reimbursement and tax equalization
         in accordance with the Company's normal programs.

                  6.     Termination.

                         (a)     Executive's employment hereunder may be
         terminated by the Company, on the one hand, or Executive, on the other
         hand, as applicable, without any breach of this Agreement, under the
         following circumstances

                                  (i) Death. Executive's employment hereunder
                  shall terminate upon Executive's death.

                                  (ii) Disability. If Executive has incurred a
                  Disability, the Company may give Executive written notice of
                  its intention to terminate Executive's employment. In such
                  event, Executive's employment with the Company shall terminate
                  effective on the 14th day after receipt of such notice by
                  Executive, provided that within the 14 days after such
                  receipt, Executive shall not have returned to full-time
                  performance of Executive's duties.

                                  (iii) Cause. The Company may terminate
                  Executive's employment hereunder for Cause.

                                  (iv) Good Reason. Executive may terminate
                  Executive's employment for Good Reason.

                                  (v) Without Cause. The Company may terminate
                  Executive's employment hereunder without Cause.

                                  (vi) Resignation without Good Reason.
                  Executive may resign Executive's employment without Good
                  Reason upon 90 days written notice to the Company.




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                         (b)     Notice of Termination. Any termination of
         Executive's employment by the Company or by Executive under this
         Section 6 (other than termination pursuant to Paragraph 6(a)(i)) shall
         be communicated by a written notice (the "Notice of Termination") to
         the other party hereto indicating the specific termination provision in
         this Agreement relied upon, setting forth in reasonable detail any
         facts and circumstances claimed to provide a basis for termination of
         Executive's employment under the provision so indicated, and specifying
         a Date of Termination which, except in the case of termination for
         Cause or Disability, shall be at least ninety (90) days following the
         date of such notice ( the "Notice Period"); provided that the Company
         may pay to Executive all Salary, benefits and other rights due to
         Executive during such Notice Period instead of employing Executive
         during such Notice Period.

                         (c)     Upon Executive's Termination of employment with
         the Company for whatever reason, he shall be deemed to have effectively
         resigned from all executive, director or other positions with the
         Company or its affiliates at the time of Termination, and shall return
         all property owned by the Company and in Executive's possession at that
         time.

                  7.     Severance Payments. Other than as set forth below, no
payments or benefits shall be due to Executive in connection with a termination
of this Agreement other than Salary and Benefits earned prior to the date of
termination.

                         (a)     Termination without Cause or for Good Reason.
         If Executive's employment shall be terminated by the Company without
         Cause (pursuant to Section 6(a)(v)), or by the Executive for Good
         Reason (pursuant to Section 6(a)(iv)), and subject to the Company's
         receipt of a general release in its customary form, the Company shall

                                  (i) pay to Executive (A) all base Salary due
                  for the period prior to termination, plus (B) either a lump
                  sum cash payment as soon as practicable following the Date of
                  Termination, or, in the Company's discretion, in twenty-four
                  (24) monthly installments in accordance with the Company's
                  normal payroll practices, an amount equal to two (2) times the
                  sum of (i) Executive's then-current rate of Annual Base Salary
                  and (ii) the Bonus Executive was awarded in the prior year
                  (the "Bonus Portion"), provided that such Bonus Portion shall
                  not be less than 60% of Executive Deemed Bonus and provided
                  further that, if Executive's employment shall be so terminated
                  by the Company within two years after a Change of Control,
                  such Bonus Portion shall not be less than two (2) times
                  Executive's Deemed Bonus;

                                  (ii) accelerate the vesting of the Options
                  referred to in Paragraph 5(c) hereof as are necessary to
                  result in Executive's having after such acceleration, when
                  considered with such Options vesting prior to such
                  acceleration, not less than the greater of (a) 125,000 or (b)
                  the sum of (x) that portion already vested and (y) an
                  additional 83,250 options;




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                                  (iii) accelerate the removal of restrictions
                  on the Restricted Shares referred to in Paragraph 5(d) hereof
                  as are necessary to result in Executive's having after such
                  acceleration, when considered with such Restricted Shares
                  having had their restriction removed prior to such
                  acceleration, a minimum of 24,000 Restricted Shares no longer
                  subject to such restrictions;

                                  (iv) continue to provide Executive with all
                  employee benefits and perquisites which Executive was
                  participating in or receiving at the time of termination of
                  employment until the earlier of two years from the Date of
                  Termination or Executive's receipt of comparable benefits from
                  a successor employer;

                                  (v) pay the cost of up to 24 months, as
                  required, of executive-level out-placement services (including
                  the use of an office and secretarial support); and

                                  (v) if Executive has relocated his primary
                  residence as set forth in Paragraph 5(h) hereof, pay the cost
                  of relocating the household furnishings and personal effects
                  of Executive (and, if applicable, his family) to Chicago at
                  any time up to six (6) months after termination.

                         (b)     Termination by Reason of Disability or Death.
         If Executive's employment shall terminate by reason of Executive's
         Disability (pursuant to Section 6(a)(ii)) or death (pursuant to Section
         6(a)(i)), and subject (is the case of a termination due to Executive's
         disability) to the Company's receipt of a general release in its
         customary form, the Company shall pay to Executive, in a lump sum cash
         payment as soon as practicable following the Date of Termination, all
         unpaid Base Salary due for the period prior to Termination plus the
         prorated portion of the unpaid Bonus to which Executive would otherwise
         be entitled for the compensation period of termination and, if there is
         a period of time during which Executive is not being paid Salary and
         not receiving long-term disability insurance payments, the Committee
         may, in its discretion, determine that the Company shall make interim
         payments to Executive until commencement of disability insurance
         payments.

                         (c)     Survival. The expiration or termination of the
         Term shall not impair the rights or obligations of any party hereto
         which shall have accrued hereunder prior to such expiration.

                  8.     Parachute Payments.

                         (d)     If it is determined (as hereafter provided)
         that by reason of any payment or Option vesting occurring pursuant to
         the terms of this Agreement (or otherwise under any other agreement,
         plan or program) upon a Change in Control (collectively a "Payment")
         the Executive would be subject to the excise tax imposed by Code
         Section 4999 or successor provision (the "Parachute Tax"), then the
         Executive shall be entitled to receive an additional payment or
         payments (a "Gross- Up Payment") in an amount such that, after payment
         by the Executive of all taxes (including any Parachute Tax) imposed
         upon the Gross- Up Payment, the Executive retains an amount of the
         Gross-Up Payment equal to the Parachute Tax imposed upon the Payment.




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                         (e)     Subject to the provisions of Section 8(a)
         hereof, all determinations required to be made under this Section 8,
         including whether a Parachute Tax is payable by the Executive and the
         amount of such Parachute Tax and whether a Gross-Up Payment is required
         and the amount of such Gross-Up Payment, shall be made by the
         nationally recognized firm of certified public accountants (the
         "Accounting Firm") used by the Company prior to the Change in Control
         (or, if such Accounting Firm declines to serve, the Accounting Firm
         shall be a nationally recognized firm of certified public accountants
         selected by the Executive). The Accounting Firm shall be directed by
         the Company or the Executive to submit its preliminary determination
         and detailed supporting calculations to both the Company and the
         Executive within 15 calendar days after the determination date, if
         applicable, and any other such time or times as may be requested by the
         Company or the Executive. If the Accounting Firm determines that any
         Parachute Tax is payable by the Executive, the Company shall pay the
         required Gross-Up Payment to, or for the benefit of, the Executive
         within five business days after receipt of such determination and
         calculations. If the Accounting Firm determines that no Parachute Tax
         is payable by the Executive, it shall, at the same time as it makes
         such determination, furnish the Executive with an opinion that he has
         substantial authority not to report any Parachute Tax on his federal
         tax return. Any good faith determination by the Accounting Firm as to
         the amount of the Gross-Up Payment shall be binding upon the Company
         and the Executive absent a contrary determination by the Internal
         Revenue Service or a court of competent jurisdiction; provided,
         however, that no such determination shall eliminate or reduce the
         Company's obligation to provide any Gross-Up Payments that shall be due
         as a result of such contrary determination. As a result of the
         uncertainty in the application of Code Section 4999 at the time of any
         determination by the Accounting Firm hereunder, it is possible that
         Gross-Up Payments that will not have been made by the Company should
         have been made (an "Underpayment"), consistent with the calculations
         required to be made hereunder. In the event that the Company exhausts
         or fails to pursue its remedies pursuant to Section 8(f) hereof and the
         Executive thereafter is required to make a payment of any Parachute
         Tax, the Executive shall direct the Accounting Firm to determine the
         amount of the Underpayment that has occurred and to submit its
         determination and detailed supporting calculations to both the Company
         and the Executive as promptly as possible. Any such Underpayment shall
         be promptly paid by the Company to, or for the benefit of, the
         Executive within five business days after receipt of such determination
         and calculations.

                         (f)     The Company and the Executive shall each
         provide the Accounting Firm access to and copies of any books, records
         and documents in the possession of the Company or the Executive, as the
         case may be, reasonably requested by the Accounting Firm, and otherwise
         cooperate with the Accounting Firm in connection with the preparation
         and issuance of the determination contemplated by Section 8(b) hereof.

                         (g)     The federal tax returns filed by the Executive
         (or any filing made by a consolidated tax group which includes the
         Company) shall be prepared and filed on a basis consistent with the
         determination of the Accounting Firm with respect to the





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         Parachute Tax payable by the Executive. The Executive shall make proper
         payment of the amount of any Parachute Tax, and at the request of the
         Company, provide to the Company true and correct copies (with any
         amendments) of his federal income tax return as filed with the Internal
         Revenue Service, and such other documents reasonably requested by the
         Company, evidencing such payment. If prior to the filing of the
         Executive's federal income tax return, the Accounting Firm determines
         in good faith that the amount of the Gross-Up Payment should be
         reduced, the Executive shall within five business days pay to the
         Company the amount of such reduction.

                         (h)     The fees and expenses of the Accounting Firm
         for its services in connection with the determinations and calculations
         contemplated by Sections 8(b) and (d) hereof shall be borne by the
         Company. If such fees and expenses are initially advanced by the
         Executive, the Company shall reimburse the Executive the full amount of
         such fees and expenses within five business days after receipt from the
         Executive of a statement therefor and reasonable evidence of his
         payment thereof.

                         (i)     In the event that the Internal Revenue Service
         claims that any payment or benefit received under this Agreement
         constitutes an "excess parachute payment" within the meaning of Code
         Section 280G(b)(1), or successor provision, the Executive shall notify
         the Company in writing of such claim. Such notification shall be given
         as soon as practicable but not later than 10 business days after the
         Executive is informed in writing of such claim and shall apprise the
         Company of the nature of such claim and the date on which such claim is
         requested to be paid. The Executive shall not pay such claim prior to
         the expiration of the 30 day period following the date on which the
         Executive gives such notice to the Company (or such shorter period
         ending on the date that any payment of taxes with respect to such claim
         is due). If the Company notifies the Executive in writing prior to the
         expiration of such period that it desires to contest such claim, the
         Executive shall (i) give the Company any information reasonably
         requested by the Company relating to such claim; (ii) take such action
         in connection with contesting such claim as the Company shall
         reasonably request in writing from time to time, including without
         limitation, accepting legal representation with respect to such claim
         by an attorney reasonably selected by the Company and reasonably
         satisfactory to the Executive; (iii) cooperate with the Company in good
         faith in order to effectively contest such claim; and (iv) permit the
         Company to participate in any proceedings relating to such claim;
         provided, however, that the Company shall bear and pay directly all
         costs and expenses (including, but not limited to, additional interest
         and penalties and related legal, consulting or other similar fees)
         incurred in connection with such contest and shall indemnify and hold
         the Executive harmless, on an after-tax basis, for and against for any
         Parachute Tax or income tax or other tax (including interest and
         penalties with respect thereto) imposed as a result of such
         representation and payment of costs and expenses.

                         (j)     The Company shall control all proceedings taken
         in connection with such contest and, at its sole option, may pursue or
         forgo any and all administrative appeals, proceedings, hearings and
         conferences with the taxing authority in respect of such claim and may,
         at its sole option, either direct the Executive to pay the tax claimed




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         and sue for a refund or contest the claim in any permissible manner and
         the Executive agrees to prosecute such contest to a determination
         before any administrative tribunal, in a court of initial jurisdiction
         and in one or more appellate courts, as the Company shall determine;
         provided, however, that if the Company directs the Executive to pay
         such claim and sue for a refund, the Company shall advance the amount
         of such payment to the Executive on an interest-free basis, and shall
         indemnify and hold the Executive harmless, on an after tax basis, from
         any Parachute Tax (or other tax including interest and penalties with
         respect thereto) imposed with respect to such advance or with respect
         to any imputed income with respect to such advance; and provided,
         further, that if the Executive is required to extend the statue of
         limitations to enable the Company to contest such claim, the Executive
         may limit this extension solely to such contested amount. The Company's
         control of the contest shall be limited to issues with respect to which
         a corporate deduction would be disallowed pursuant to Code Section 280G
         or successor provision, and the Executive shall be entitled to settle
         or contest, as the case may be, any other issue raised by the Internal
         Revenue Service or any other taxing authority. In addition, no position
         may be taken nor any final resolution be agreed to by the Company
         without the Executive's consent if such position or resolution could
         reasonably be expected to adversely affect the Executive unrelated to
         matters covered hereto.

                         (k)     If, after the receipt by Executive of an amount
         advanced by the Company in connection with the contest of the Parachute
         Tax claim, the Executive receives any refund with respect to such
         claim, the Executive shall promptly pay to the Company the amount of
         such refund (together with any interest paid or credited thereon after
         taxes applicable thereto); provided, however, if the amount of that
         refund exceeds the amount advanced by the Company the Executive may
         retain such excess. If, after the receipt by the Executive of an amount
         advanced by the Company in connection with a Parachute Tax claim, a
         determination is made that the Executive shall not be entitled to any
         refund with respect to such claim and the Company does not notify the
         Executive in writing of its intent to contest the denial of such refund
         prior to the expiration of 30 days after such determination such
         advance shall be deemed to be in consideration for services rendered
         after the Date of Termination.

                  9.     Competition.

                         (a)     Executive shall not, at any time during the
         Term, or for one year thereafter, without the prior written consent of
         the Board, directly or indirectly through any other person or entity:

                                  (i) own, acquire in any manner any ownership
                  interest in (except as purely passive investments amounting to
                  no more than five percent of the voting equity), or serve as a
                  director, officer, employee, counsel or consultant of any
                  person, firm, partnership, corporation, consortia, association
                  or other entity that competes with the Company or any of its
                  affiliates or subsidiaries, in any geographic market in which
                  the Company either (A) offers or provides telecommunications
                  (which term hereafter shall be deemed to include voice, data
                  or internet communications) services to customers; (B)
                  operates or manages a




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                  provider of telecommunications services; (C) has investments
                  in a provider of telecommunications services; or (D), to
                  Executive's knowledge, has plans to either operate a
                  telecommunications carrier, offer a telecommunications
                  service, or invest in a telecommunications carrier within the
                  next twelve months,

                                  (ii) solicit, entice, persuade or induce any
                  individual who currently is, or at any time during the
                  preceding twelve months shall have been, an officer, director
                  or employee of the Company, or any of its affiliates, to
                  terminate or refrain from renewing or extending such person's
                  employment with the Company or such subsidiary or affiliate,
                  or to become employed by or enter into contractual relations
                  with or consultant for any other individual or entity, and
                  Executive shall not approach any such employee for any such
                  purpose or authorize or knowingly cooperate with the taking of
                  any such actions by any other individual or entity, or

                                  (iii) except in accordance with Executive's
                  duties on behalf of the Company, solicit, entice, persuade, or
                  induce any individual or entity which currently is, or at any
                  time during the preceding twelve months shall have been, a
                  customer, consultant, vendor, supplier, lessor or lessee of
                  the Company, or any of its subsidiaries or affiliates, to
                  terminate or refrain from renewing or extending its
                  contractual or other relationship with the Company or such
                  subsidiary or affiliate, and Executive shall not approach any
                  such customer, vendor, supplier, consultant, lessor or lessee
                  for such purpose or authorize or knowingly cooperate with the
                  taking of any such actions by any other individual or entity.

                         (b)     Executive shall not at any time:

                                  (iv) other than when required in the ordinary
                  course of business of the Company, disclose, directly or
                  indirectly, to any person, firm, corporation, partnership,
                  association or other entity, any trade secret, or confidential
                  information concerning the financial condition, suppliers,
                  vendors, customers, lessors, or lessees, sources or leads for,
                  and methods of obtaining, new business, or the methods
                  generally of doing and operating the respective businesses of
                  the Company or its affiliates and subsidiaries to the degree
                  such secret or information incorporates information that is
                  proprietary to, or was developed specifically by or for, the
                  Company, except such information that is a matter of public
                  knowledge, was provided to Executive (without breach of any
                  obligation of confidence owed to the Company) by a third party
                  which is not an affiliate of the Company, or is required to be
                  disclosed by law or judicial or administrative process, or

                                  (v) make any oral or written statement about
                  the Company and/or its financial status, business, compliance
                  with laws, personnel, directors, officers, consultants,
                  services, business methods or otherwise, which is intended or
                  reasonably likely to disparage the Company or otherwise
                  degrade its reputation in the business or legal community in
                  which it operates or in the telecommunications industry;




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<PAGE>   13




                  provided that nothing in this Section 9(b) shall be construed
                  so as to prevent Executive from using, in connection with his
                  employment for himself or an employer other than the Company,
                  knowledge that was acquired by him during the course of his
                  employment with the Company and which is generally known to
                  persons of his experience in other companies in the same
                  industry;

                         (c)     Executive hereby represents that (i) Executive
         is not restricted in any material way from performing Executive's
         duties hereunder as the result of any contract, agreement or law; and
         (ii) Executive's due performance of Executive's duties hereunder does
         not and will not violate the terms of any agreement to which Executive
         is bound.

                         (d)     In the event any agreement in Section 9 hereof
         shall be determined by any court of competent jurisdiction to be
         unenforceable by reason of its extending for too great a period of time
         or over too great a geographical area or by reason of its being too
         extensive in any other respect, it will be interpreted to extend only
         over the maximum period of time for which it may be enforceable, and/or
         over the maximum geographical area as to which it may be enforceable
         and/or to the maximum extent in all other respects as to which it may
         be enforceable, all as determined by such court in such action.

                  10.    Injunctive Relief. It is recognized and acknowledged by
Executive that a breach of the covenants contained in Section 9 hereof will
cause irreparable damage to the Company and its goodwill, the exact amount of
which will be difficult or impossible to ascertain, and that the remedies at law
for any such breach will be inadequate. Accordingly, Executive agrees that in
the event of a breach of any of the covenants contained in Section 9 hereof, in
addition to any other remedy which may be available at law or in equity, the
Company will be entitled to specific performance and injunctive relief.

                  11.    Mutual Non-Disparagement. Neither the Company nor
Executive shall make any oral or written statement about the other party which
is intended or reasonably likely to disparage the other party, or otherwise
degrade the other party's reputation in the business or legal community or in
the telecommunications industry.

                  12.    Foreign Corrupt Practices Act. Executive agrees to
comply in all material respects with the applicable provisions of the U.S.
Foreign Corrupt Practices Act of 1977 ("CPA"), as amended, which provides
generally that: under no circumstances will foreign officials, representatives,
political parties or holders of public offices be offered, promised or paid any
money, remuneration, things of value, or provided any other benefit, direct or
indirect, in connection with obtaining or maintaining contracts or orders
hereunder. When any representative, employee, agent, or other individual or
organization associated with Executive is required to perform any obligation
related to or in connection with this Agreement, the substance of this section
shall be imposed upon such person and included in any agreement between
Executive and any such person. Failure by Executive to comply with the
provisions of the CPA shall constitute a material breach of this Agreement and
shall entitle the Company to terminate Executive's employment for Cause.
Additionally, Executive hereby acknowledges that as a condition for the Company
to continue this Agreement, Executive shall execute an






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acknowledgment that Executive has read "An Explanation of the Foreign Corrupt
Practices Act" and "Global TeleSystems Group, Inc. Policy on Foreign
Transactions," copies of which have been provided to Executive. Executive also
acknowledges that a condition precedent to the effectiveness of this Agreement
shall be the execution by Executive of the "Addendum to the Global TeleSystems
Group, Inc. Policy on Foreign Transaction," a copy of which has been provided to
Executive. Additionally, and as a condition for the Company to continue this
Agreement, Executive shall be required from time to time at the request of the
Company to execute a certificate of Executive's compliance with the
aforementioned laws and regulations.

                  13.    Purchases and Sales of the Company's Securities.
Executive has read and agrees to comply in all respects with the Company's
Policy Regarding the Purchase and Sale of the Company's Securities by Employees,
as such Policy may be amended from time to time. Specifically, and without
limitation, Executive agrees that Executive shall not purchase or sell stock in
the Company at any time (a) that Executive possesses material non-public
information about the Company or any of its businesses; and (b) during any
"Trading Blackout Period" as may be determined by the Company as set forth in
the Policy from time to time.

                  14.    Indemnification. Executive shall be entitled to
indemnification set forth in the Company's Certificate of Incorporation to the
maximum extent allowed under the laws of the Commonwealth of Virginia and the
State of Delaware Corporations Act, and Executive shall be entitled to the
protection of any insurance policies the Company may elect to maintain generally
for the benefit of its directors and officers against all costs, charges and
expenses incurred or sustained by Executive in connection with any action, suit
or proceeding to which Executive may be made a party by reason of Executive's
being or having been a director, officer or employee of the Company or any of
its subsidiaries or Executive's serving or having served any other enterprise as
a director, officer or employee at the request of the Company (other than any
dispute, claim or controversy arising under or relating to this Agreement).

                  15.    Notices. Any written notice required by this Agreement
will be deemed provided and delivered to the intended recipient when (a)
delivered in person by hand; or (b) three days after being sent via U.S.
certified mail, return receipt requested; or (c) the day after being sent via by
overnight courier, in each case when such notice is properly addressed to the
following address and with all postage and similar fees having been paid in
advance:

         If to the Company:   Global TeleSystems Group, Inc.
                              Attn.: Senior Vice President for Human Resources
                              1751 Pinnacle Drive
                              North Tower 12th Floor
                              McLean, VA  22102  USA


         If to Executive:     to Executive at the address set forth below under
                              Executive's signature.

Either party may change the address to which notices, requests, demands and
other communications to such party shall be delivered personally or mailed by
giving written notice to the other party in the manner described above.




                                       14
<PAGE>   15




                  16.    Binding Effect. This Agreement shall be for the benefit
of and binding upon the parties hereto and their respective heirs, personal
representatives, legal representatives, successors and, where applicable,
assigns.

                  17.    Entire Agreement. This Agreement constitutes the entire
agreement between the listed parties with respect to the subject matter
described in this Agreement and supersedes all prior agreements, understandings
and arrangements, both oral and written, between the parties with respect to
such subject matter. This Agreement may not be modified, amended, altered or
rescinded in any manner, except by written instrument signed by both of the
parties hereto; provided, however, that the waiver by either party of a breach
or compliance with any provision of this Agreement shall not operate nor be
construed as a waiver of any subsequent breach or compliance.

                  18.    Severability. In case any one or more of the provisions
of this Agreement shall be held by any court of competent jurisdiction or any
arbitrator selected in accordance with the terms hereof to be illegal, invalid
or unenforceable in any respect, such provision shall have no force and effect,
but such holding shall not affect the legality, validity or enforceability of
any other provision of this Agreement provided that the provisions held illegal,
invalid or unenforceable does not reflect or manifest a fundamental benefit
bargained for by a party hereto.

                  19.    Dispute Resolution and Arbitration. In the event that
any dispute arises between the Company and Executive regarding or relating to
this Agreement and/or any aspect of Executive's employment relationship with the
Company, AND IN LIEU OF LITIGATION AND A TRIAL BY JURY, the parties consent to
resolve such dispute through mandatory arbitration under the Commercial Rules of
the American Arbitration Association ("AAA"), before a single arbitrator in
McLean or Alexandria, Virginia. The parties hereby consent to the entry of
judgment upon award rendered by the arbitrator in any court of competent
jurisdiction. Notwithstanding the foregoing, however, should adequate grounds
exist for seeking immediate injunctive or immediate equitable relief, any party
may seek and obtain such relief; provided that, upon obtaining such relief, such
injunctive or equitable action shall be stayed pending the resolution of the
arbitration proceedings called for herein. The parties hereby consent to the
exclusive jurisdiction in the state and Federal courts of or in the Commonwealth
of Virginia for purposes of seeking such injunctive or equitable relief as set
forth above. Any and all out-of-pocket costs and expenses incurred by the
parties in connection with such arbitration (including attorneys' fees) shall be
allocated by the arbitrator in substantial conformance with his or her decision
on the merits of the arbitration; provided, however, that in no event shall
Executive be required to pay attorneys' fees in an amount that exceeds the
amount incurred by Executive for Executive's attorneys' fees.

                  20.    Choice of Law. Executive and the Company intend and
hereby acknowledge that jurisdiction over disputes with regard to this
Agreement, and over all aspects of the relationship between the parties hereto,
shall be governed by the laws of the Commonwealth of Virginia without giving
effect to its rules governing conflicts of laws.

                  21.    Section Headings. The section headings contained in
this Agreement are for reference purposes only and shall not affect in any
manner the meaning or interpretation of this Agreement.




                                       15
<PAGE>   16



                  22.    Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be deemed an original, but all of
which taken together shall constitute one and the same instrument.


                  IN WITNESS WHEREOF, the parties have executed this Agreement
on the date and year first above written.

                                         GLOBAL TELESYSTEMS GROUP, INC.



                                         By: /s/ Eileen Sweeney
                                         Name: Eileen Sweeney
                                         Title: Senior VP - Human Resources


                                         EXECUTIVE

                                         /s/ Robert A. Schriesheim




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