Employment Agreement - Frontier Corp. and Joseph P. Clayton


                                   May 1, 1999


Mr. Joseph P. Clayton
20 Windham Hill
Mendon, New York  14506


Dear Mr. Clayton:

                  As you know, Frontier Corporation (the 'Company') has entered
into an agreement which would constitute a Change of Control pursuant to the
agreement between yourself and the Company dated January 1, 1998 (the 'COC
Agreement'). In contemplation of a Change of Control, the Company and you agree
to amend your COC Agreement as follows:

         1.       Section 4.2.3(b) is amended to read as follows:

                  (b) The period of your employment by the Company (whether
                  under this Agreement or otherwise) and 24 months thereafter,
                  if your employment is terminated, prior to a Change of Control
                  (i) because of your Retirement, or (ii) by the Company for
                  Cause or without Cause;

         2.       Section 4.2.3(d) is amended to read as follows:

                  (d) On and after a Change of Control has occurred, or if your
                  employment is terminated for Good Reason, the period of your
                  employment by the Company under this Agreement.

         3.       The third sentence of Section 7.1.5 is amended to read as
                  follows:

                  The term 'Bonus Amount' means the greatest of: (i) your annual
                  cash performance bonus under the Company's bonus program at
                  the premier target level for the year in which the Termination
                  Date occurs, but no lower than the premier target level
                  established and in effect prior to March 16, 1999; (ii) the
                  bonus paid or payable to you with respect to the fiscal year
                  preceding the year in which the Termination Date occurs; or
                  (iii) following a Change of Control, the bonus paid to you
                  with respect to the fiscal year preceding the year in which
                  the Change of Control occurred.

 
         4.       Section 7.2 is amended to read as follows:

                  7.2 Termination Without Cause. If the Company terminates your
                  employment without Cause (as defined later in this Agreement)
                  prior to a Change of Control, the Company shall pay you:

                  7.2.1  All Accrued Compensation;

                  7.2.2  A Pro Rata Bonus (as defined in Section 7.1.5 above);
                         and

                  7.2.3  Severance ('Severance') equal to twice the sum of (i)
                  the annual base compensation you would have received for the
                  entire fiscal year in which the Termination Date occurs plus
                  (ii) the Bonus Amount plus (iii) $40,000, or if greater, the
                  1999 cash equivalent of the annual value of the perquisites
                  provided to you under the Company's Executive Compensation
                  Program plus (iv) the Company contributions which would have
                  been made on your behalf to the 401(k) retirement savings plan
                  maintained by the Company for the year of your termination
                  plus (v) the Company allocation which would have been made to
                  your account in the Company's Supplemental Retirement Savings
                  Plan (or any successor thereto) for the year of your
                  termination. The foregoing shall be in lieu of any other
                  amount of severance relating to salary or bonus continuation
                  to be received by you upon termination of your employment
                  under any severance plan, policy or arrangement of the
                  Company.

                  In addition, the Company shall continue to provide to you and
                  your family at the Company's expense, for 24 months following
                  the Termination Date, the life insurance, disability, medical,
                  dental, vision and hospitalization benefits provided to you
                  and (other than for disability) your family immediately prior
                  to the Termination Date.

                  Except as otherwise provided in this Section 7.2, your
                  entitlement to any other compensation or benefits shall be
                  determined in accordance with the Company's employee benefit
                  plans and other applicable programs and practices then in
                  effect.

         5.       The first phrase of the introductory sentence of Section 7.4
                  is amended to read as follows:

 
                  7.4 Termination by Company Following Change of Control or
                  Termination for Good Reason. If the Company terminates your
                  employment on and after a Change of Control, or you terminate
                  your employment for Good Reason (whether or not you elect to
                  retire, if eligible), the Company shall pay you:

         6.       The first paragraph of Section 7.4.3 is amended to read as
                  follows:

                  7.4.3 Severance equal to three times the sum of (i) the annual
                  base compensation you would have received for the entire
                  fiscal year in which the Termination Date occurs plus (ii) the
                  Bonus Amount plus (iii) $40,000, or if greater, the 1999 cash
                  equivalent of the annual value of the perquisites provided to
                  you under the Company's Executive Compensation Program plus
                  (iv) the Company contributions which would have been made on
                  your behalf to the 401(k) retirement savings plan maintained
                  by the Company for the year of your termination plus (v) the
                  Company allocation which would have been made to your account
                  in the Company's Supplemental Retirement Savings Plan (or any
                  successor thereto) for the year of your termination. The
                  foregoing severance shall be in lieu of any other amount of
                  severance relating to salary or bonus continuation to be
                  received by you upon termination of your employment under any
                  severance plan, policy or arrangement of the Company.

         7.       The paragraph immediately following Section 7.4.3 shall be
                  amended to read as follows:

                  In addition, the Company shall continue to provide to you and
                  your family at the Company's expense, for 36 months following
                  the Termination Date, the life insurance, disability, medical,
                  dental, vision and hospitalization benefits provided to you
                  and (other than for disability) your family immediately prior
                  to the Termination Date.

         8.       The following proviso is added to the end of Section 9:

                  ; provided, however, that on and after a Change of Control
                  neither the Company nor any other person shall be permitted to
                  terminate any payments or benefits under the terms of this
                  section.

         9.       Section 12.1.3 is amended to read as follows:

 
                  12.1.3 You have willfully engaged in conduct which is illegal
                  or in violation of the Company's Code of Ethics; provided,
                  however, that on and after a Change of Control this Section
                  12.1.3 shall be of no force and effect; or

         10.      Section 12.1.4 is amended to read as follows:

                  12.1.4 You have been convicted of a felony or a crime
                  involving moral turpitude; provided, however, that on and
                  after a Change of Control this Section 12.1.4 shall be limited
                  to apply only to the conviction of a felony; or

         11.      Section 12.4.7 is renumbered to be Section 12.4.8 and the
                  following Section 12.4.7 is added:

                  12.4.7 Without your express written consent, after a Change of
                  Control, any requirement that you relocate your principal
                  place of business more than 50 miles from your principal place
                  of business immediately prior to such Change of Control or any
                  substantial increase in business related travel over the level
                  of travel required immediately prior to the Change of Control;
                  or

         12.      The term 'Retirement' above is used in the event you are or
                  are currently entitled to become retirement eligible, and does
                  not create new retirement eligibility. In the absence of a
                  definition in your existing agreement, for purposes of this
                  COC Amendment, the following definition applies:

                  'Retirement' shall, for each affected plan or agreement
                  involving you and the Company, have the meaning established in
                  the applicable plan or agreement, or in the absence of a
                  definition or consistently applied interpretation, shall mean
                  a voluntary or involuntary termination of your employment
                  after age 65, or at age 65 or earlier, with age and service
                  credits that would, in such case, entitle you to receive a
                  normal or early retirement service pension under the Frontier
                  Management Pension Plan (or any successor or substitute plan
                  or plans of Frontier instituted prior to March 16, 1999.)

         Three signed copies of this amendment have been enclosed. The
amendments being made herein are being made pursuant to authorization of the
board of directors of the Company. Your agreement and this COC Amendment will
not adversely impact the validity or treatment of any separate agreement that
you have 

 
with the Company with respect to options, loan forgiveness or the like that was
in place as of March 16, 1999.

         If you agree to the above mentioned changes to your COC Agreement,
please sign all copies below and return two of the signed original agreements to
Mr. McCue.

                                   Sincerely,



                                   /s/Douglas H. McCorkindale
                                   --------------------------------
                                   Douglas H. McCorkindale



Agreed and Accepted:



/s/Joseph P. Clayton
---------------------------
Joseph P. Clayton