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                                                                   Exhibit 10.18

                       RETIREMENT AND EMPLOYMENT AGREEMENT


                  This AGREEMENT (the "AGREEMENT") is made as of the 7th day of
December, 2000 by and among MPOWER COMMUNICATIONS CORP., a Nevada corporation
(the "COMPANY") and Kent F. Heyman ("EXECUTIVE"). Capitalized terms that are not
otherwise defined within the text of this Agreement are defined in Section 6
hereof.

                  WHEREAS, Executive has retired effective December 31, 2000, as
the Senior Vice President & General Counsel of the Company; and

                  WHEREAS, the Company has determined that it is in its best
interests that Executive's employment with the Company continue and Executive
desires to continue his employment with the Company subsequent to his retirement
and that this Agreement supercedes any and all prior written or oral agreements
and understandings with the Company.

                  NOW, THEREFORE, in consideration of the premises and the
covenants and agreements herein contained, the parties hereto agree as follows:

                  1. EMPLOYMENT TERM. The Executive began employment with the
Company on June 1, 1996 and retired effective December 31, 2000. Subject to
earlier termination in accordance with the provisions of this Agreement, the
Agreement shall become effective as of the date hereof and the new term of
Executive's employment with the Company pursuant to this Agreement (the "TERM")
shall begin on January 1, 2001 and continue until December 31, 2001.

                  2. DUTIES. Effective January 1, 2001, Executive shall serve
the Company in such capacity as determined by the Chief Executive Officer (the
"CEO") of the Company and, as needed, shall perform such duties as the CEO or
such other persons as appointed by the CEO, may designate. Such duties shall be
the same as or similar to those performed by Executive prior to the date hereof.
Executive agrees that during the Term, Executive at the sole discretion of the
CEO may be required to spend up to 30% of his work day performing services for
the Company and shall not work as an employee, agent or representative for any
other person, firm or entity where such activity would violate Article 5 of this
Agreement. Effective January 1, 2001, the Executive's primary work location
shall be his choosing but he may be required to travel when necessary to perform
his services for the Company.

                  3. COMPENSATION AND BENEFITS.

                  3.01 FIXED SALARY. During the Term, as compensation for
Executive's services, the Company shall pay Executive a salary at the rate of
$180,000 per annum until December 31, 2000; the additional sum of $94,500 on
January 1, 2001 as retirement severance (the "Severance"); and a salary totaling
$40,500 for the period January 1, 2001 through December 31, 2001 (the "FIXED
SALARY"). The Fixed Salary shall be paid as follows: $3,375 per month through
December 31, 2001. The Severance and Fixed Salary payments shall be made less
appropriate payroll deductions as required by law.


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                  3.02 ANNUAL BONUS. During the Term, Executive shall be
eligible to receive his annual bonus for 2000, with the amount determined by the
Company in accordance with its customary procedures and standards applicable to
the 2000 bonus for other Senior Vice Presidents. The Executive waives his right
to any bonus for 2001.

                  3.03 INITIAL STOCK OPTION AWARDS. The Executive has received
one or more awards of options (the "INITIAL AWARD") to purchase shares of the
Company's common stock at exercise prices set forth in one or more of various
stock option agreements. A summary of the Executive's existing options are
attached as Appendix A hereto. The Executive's Initial Award will remain subject
to the terms and conditions of the applicable stock option agreements. More
specifically, the Executive's options shall continue to vest until the
Termination Date, and the Executive shall have the right to exercise his vested
options at any time prior to the Termination Date and for a period of thirty
(30) days thereafter. Any options that have not vested as of the Termination
Date shall be forfeited. Notwithstanding the foregoing, in the event the
Executive is terminated without Cause, his options shall continue to vest
through December 31, 2001, and his right to exercise all vested options shall
continue through January 31, 2002. All the Executive's options shall fully vest
in the event of a change of control of the Company prior to the Termination
Date, or prior to December 31, 2001 in the event the Executive has been
terminated without Cause. The term "CHANGE OF CONTROL" shall be defined by the
definition in the Company's current Stock Option Plan.

                  3.04 EXPENSES. Through the Termination Date, the Company shall
pay or reimburse Executive for all reasonable business expenses incurred in the
performance of Executive's duties and which are consistent with the Company's
policies, practices and procedures, upon submission of appropriate vouchers and
other supporting data.

                  3.05 BENEFITS. Through the Termination Date, and through
September 15, 2001 if the Executive is terminated without cause, Executive and
his eligible dependents shall be entitled to participate in all general pension,
profit-sharing, life, medical, disability and other insurance and benefit plans
in effect for similarly situated executives of the Company. As of December 7,
2000, all vacation accruals shall cease, any unused vacation balance will be
paid out in accordance with the company's policy on December 31, 2000.

         3.06 LOANS. Upon the satisfactory completion by the Executive of his
obligations under this Agreement, and in particular, but not limited to, him
obligations to perform services until September 15, 2001 and his further
obligations pursuant to Section 5, the Company shall (i) waive the Company's
right, if any, to repurchase any shares of the Company's stock from the
Executive, and (ii) permit the outstanding loans of the Executive to be repaid
in thirty-six (36) equal monthly installments of principal and interest (at the
rate of six percent (6%) per annum, compounded quarterly), with such payments to
commence of the Termination Date. In the event of a breach of any of the terms
and conditions of this Agreement, or the Executive's resignation prior to
September 15, 2001 or termination for Cause by the Company, all balances on
loans made by the Company to the Executive shall be immediately due and payable,
and the Company shall be entitled to exercise its rights then existing with
respect to the repurchase of the Company's shares. The Executive's termination
without Cause or Executive's resignation subsequent to September 15, 2001, shall
not be deemed a breach of this Agreement nor evidence


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of the Executive's failure to perform services until September 15, 2001 or
satisfactorily complete his obligations hereunder.

                  4. TERMINATION OF EMPLOYMENT. Subject to the terms of this
Section 4, the Company may terminate Executive's employment under this Agreement
at any time and for any reason.

                  4.01 TERMINATION OR RESIGNATION BY EXECUTIVE. In the event
that, during the Term, Executive's employment is terminated by the Company for
any reason or Executive resigns from his employment hereunder for any reason,
Executive shall receive the following: (i) accrued and unpaid Fixed Salary and
reimbursement for any outstanding business expenses through the Termination
Date; (ii) the Severance payment referred to in section 3.01; and (iii) such
other accrued compensation and benefits (including post-retirement benefits) as
may be due through the Termination Date under the terms of the compensation and
benefit plans in which Executive participates. In addition, in the event that
the Executive resigns or is terminated by the Company for other than Cause,
Executive shall receive a severance payment ("the SEVERANCE BENEFITS") of a lump
sum equal to any unpaid Fixed Salary due the Executive through December 31,
2001, provided, however, that Executive's right to receive any Severance
Benefits hereunder shall be contingent upon execution by him of a Waiver and
Release of Claims in favor of the Company and its affiliates substantially in
the form set forth in Appendix B hereto, his continued availability up to thirty
percent (30%) of his workday to assist in the transition of his work and him
compliance with the obligations set forth in Section 5 of this Agreement.

                  4.02 TERMINATION DUE TO DEATH OR DISABILITY. In the event of
Executive's death or Disability, Executive's Fixed Salary shall continue to be
paid until the end of the Term to Executive or his estate, as the case may be.
Neither the Executive, nor his estate, as the case may be, shall be entitled to
continue to receive any benefits other than the Fixed Salary, proceeds from
insurance per the terms of any applicable policy and reimbursement of expenses,
and all further vesting of options shall cease.

                  4.03 NO OTHER PAYMENTS OR BENEFITS. As of the Termination
Date, other than the payments and benefits expressly provided for or referred to
in this Section 4, all obligations of the Company to Executive, other than as
required by law or provided under any applicable employee benefit plan of the
Company, shall cease.

                  4.04 NOTICE OF TERMINATION. Any termination of Executive's
employment by the Company or by Executive during the Term shall be communicated
by a Notice of Termination to the other party hereto. The Notice of Termination
shall, if applicable, indicate the specific termination provision in this
Agreement relied upon and shall set forth in reasonable detail the facts and
circumstances claimed to provide a basis for termination of Executive's
employment under the provision so indicated.

                  4.05 BREACH OF RESTRICTIVE COVENANTS. If, at any time
Executive breaches any of the provisions of Sections 5.01, 5.02, 5.03 and/or
5.05 below, he shall not be eligible, as of the date of such breach, for any
Severance Benefits described in this Section 4 and all obligations of the
Company to pay any such Severance Benefits hereunder shall thereupon cease.


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                  5. RESTRICTIVE COVENANTS.

                  5.01 CONFIDENTIALITY; NONDISCLOSURE. Executive understands and
acknowledges that in the course of Executive's employment, Executive has had and
will continue to have access to and will learn information proprietary to the
Company and its affiliates (the "COMPANY ") that concerns the technological
innovations, operation and methodology of the Company , including, without
limitation, business plans, financial information, protocols, proposals,
manuals, procedures and guidelines, computer source codes, programs, software,
know-how and specifications, copyrights, trade secrets, market information,
Developments (as hereinafter defined), data and customer information
(collectively, "PROPRIETARY INFORMATION"). "DEVELOPMENTS" shall mean all data,
discoveries, findings, reports, designs, inventions, improvements, methods,
practices, techniques, developments, programs, concepts and ideas, whether or
not patentable, relating to the present or planned activities, or the products
and services of the Company . Executive agrees that during the period beginning
on the date of his hiring and continuing in perpetuity thereafter, Executive
shall keep confidential and shall not disclose any such Proprietary Information
to any third party, except as required to fulfill Executive's duties in
connection with employment by the Company, and shall not misuse, misappropriate
or exploit such Proprietary Information in any way. The restrictions contained
herein shall not apply to any information which Executive can demonstrate (i)
was already available to the public at the time of disclosure, or subsequently
became available to the public, otherwise than by breach of this Agreement or
(ii) was the subject of a court order to disclose. Upon any termination of
Executive's employment, Executive will immediately return to the Company all
Proprietary Information and copies thereof in Executive's possession.

                  5.02 NO COMPETING EMPLOYMENT. Prior to the Termination Date,
Executive hereby acknowledges that in the course of Executive's employment with
the Company, Executive has become familiar, and will become familiar, with the
trade secrets of the Company and with other confidential information concerning
the Company , and that Executive's services have been and will be of special,
unique and extraordinary value to the Company. Therefore, Executive hereby
agrees that until the Termination Date, Executive shall not, unless Executive
receives the prior written consent of the Board of Directors of the Company (the
"BOARD"), directly or indirectly, knowingly own an interest in, manage, operate,
join, control, lend money or render financial or other assistance to or
participate in or be connected, an officer, employee, partner, stockholder,
consultant or otherwise, any individual, partnership, firm, corporation or other
business organization or entity that competes with the business of the Company
as such businesses exist or are in the process of being formed or acquired as of
the Termination Date, within any geographical area in which the Company is
engaged, services customers, or was actively planning to engage during the Term
or as of the Termination Date; PROVIDED, HOWEVER, that this Section 5.02 shall
not proscribe Executive's ownership, either directly or indirectly, of less than
one percent of any class of securities which are listed on a national securities
exchange or quoted on the automated quotation system of the National Association
of Securities Dealers, Inc. For purposes of this Agreement, an individual or
entity shall be deemed to compete with the Company if, at the time the Executive
provides services to such individual or entity, said individual or entity offers
for sale any of the services or products (i) then being offered for sale by the
Company, or (ii) which the Company has then existing plans to offer within the
next six months. A competing entity shall include, but not be limited to, RBOCs,
ILECs and CLECs.


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                  5.03 RESTRICTIONS ON SOLICITATION. During the Restricted
Period and except as required pursuant to Executive's duties to the Company in
connection with the employment relationship, Executive will not, directly or
indirectly: (i) solicit or contact any customer of the Company (or any other
entity that Executive knows is a potential customer with respect to specific
products of the Company and with which Executive have had contact during the
period of Executive's employment with the Company) for any commercial pursuit
that to Executive's knowledge is in competition with the Company , or that to
Executive's knowledge is contemplated from time to time during the period of
Executive's employment with the Company by Company 's business plan; (ii) take
away or interfere or attempt to interfere with any custom, trade, business,
patronage or other business relation of the Company , or induce, or attempt to
induce, any employees, agents or consultants of or to the Company to do anything
from which Executive is restricted by reason of this Section 5; or (iii) induce
or aid others to induce employees, agents or consultants of the Company to
terminate their employment with the Company , or interfere or attempt to
interfere with any employees, agents or consultants of the Company .

                  5.04 EXTENSION OF RESTRICTED PERIOD. The Restricted Period
shall be extended by the length of any period during which Executive is in
breach of any of the terms of Section 5 hereof.

                  5.05 ASSIGNMENT OF DEVELOPMENTS. During the Term, all
Developments that are at any time made, conceived or suggested by Executive,
whether acting alone or in conjunction with others, shall be the sole and
absolute property of the Company, free of any reserved or other rights of any
kind on Executive's part. During the Term, if such Developments were made,
conceived or suggested by Executive during or as a result of Executive's
employment relationship with the Company , thereafter, Executive shall promptly
make full disclosure of any such Developments to the Company and, at the
Company's cost and expense, do all acts and things (including, among others, the
execution and delivery under oath of patent and copyright applications and
instruments of assignment) deemed by the Company to be necessary or desirable at
any time in order to effect the full assignment to the Company, or of
Executive's right and title, if any, to such Developments. Executive
acknowledges and agrees that any invention, concept, design or discovery that
concretely relates to or is associated with Executive's work for the Company
that is described in a patent application or is disclosed to a third party
directly or indirectly by Executive during the Restricted Period shall be the
property of and owned by the Company and such disclosure by patent application
or otherwise shall constitute a breach of Section 5.01 above.

                  5.06 APPLICATION OF COVENANTS. The activities described in
this Section 5 shall be prohibited regardless of whether undertaken by Executive
in an individual or representative capacity, and regardless of whether performed
for Executive's own account or for the account of any other individual,
partnership, firm, corporation or other business organization (other than the
Company).

                  5.07 INJUNCTIVE RELIEF. Without limiting the remedies
available to the Company, Executive acknowledges that a breach of any of the
covenants contained in this Section 5 may result in material irreparable injury
to the Company for which there is no adequate remedy at law, that it will not be
possible to measure damages for such injuries precisely and


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that, in the event of such a breach or threat thereof, the Company shall be
entitled to seek a temporary restraining order or a preliminary or permanent
injunction restraining Executive from engaging in activities prohibited by this
Section 5 or such other relief as may be required to specifically enforce any of
the covenants in this Section 5.

                  5.08 REASONABLENESS OF COVENANTS. If, at the time of
enforcement of the covenants set forth in this Section 5, a court holds that the
restrictions stated herein are unreasonable under circumstances then existing,
the parties hereto agree that the maximum period, scope or geographical area
reasonable under such circumstances shall be substituted for the stated period,
scope or area.

                  5.09 VIOLATION AND REMEDY. If the Company reasonably
determines that Executive has breached any of the provisions of this Section 5,
in addition to any other remedies available to the Company in law or equity, the
Company shall be entitled to immediately suspend as of the date of such breach
the provision to Executive of any payments or benefits under this Agreement,
including without limitation, the Severance Benefit outlined in Section 4 of
this Agreement, and any Severance Benefits already paid shall be immediately
returned to the Company.

                  6. DEFINITIONS.

                  "CAUSE" shall mean a termination of Executive's employment
which is a result of any of the following: (A) his continued failure or refusal
to perform the duties of his employment pursuant to this Agreement; (B) his
breach of Article 5 of this Agreement; (C) his willful and material violation of
any federal or state law or regulation applicable to the business of the
Company, (D) his plea of no contest to or conviction of a felony involving moral
turpitude, (E) his perpetration of a common law fraud; or (F) any other willful
misconduct by Executive which is materially injurious to the Company.

                   "DISABILITY" shall mean Executive's incapacity due to
physical or mental illness which causes such Participant to be absent from the
full-time performance of Executive's duties with the Company for one-hundred and
twenty days during any twelve month period.

                  "NOTICE OF TERMINATION" shall mean the notice provided in the
event of any termination of Executive's employment by the Company or resignation
by Executive's during the Term which shall be communicated to the other party
hereto.

                  "RESTRICTED PERIOD" shall mean: (i) the period during which
Executive is employed with the Company; and (ii) following a termination of
Executive's employment with the Company for any reason, the period beginning on
the Termination Date and ending on the later of (A) the last day of the Term and
(B) the first anniversary of the Termination Date.

                  "TERMINATION DATE" shall be determined as follows: (i) if
Executive's employment is terminated for Disability, sixty days after a Notice
of Termination is given (provided that Executive shall not have returned to the
full-time performance of Executive's duties during such sixty-day period); (ii)
if Executive's employment is terminated by the Company without Cause, the date
specified in the Notice of Termination, which date shall be no earlier than 30
days after the date such notice is delivered to Executive, as the case may be
(or if


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no date is specified in the Notice of Termination, sixty days after the Notice
of Termination is received by the Company or delivered to Executive, as the case
may be); (iii) if Executive's employment is terminated by the Company for Cause,
the date specified in the Notice of Termination; (iv) in the event of
Executive's resignation of employment, the Termination Date shall be the date
set forth in the Notice of Termination, which date shall be no earlier than
thirty days after the date such notice is received by the Company; (v) the
Termination Date in the event of Executive's death shall be the date of
Executive's death; or (vi) December 31, 2001 if not terminated sooner pursuant
to this Agreement.

                  7. NOTICES. All notices under this Agreement shall be in
writing and shall be deemed to have been duly given if personally delivered
against receipt or if mailed by registered or certified mail, return receipt
requested, addressed to the Company and to Executive, at the address indicated
below or to such other person or address as may be designated by like notice
hereunder. Any such notice shall be deemed to have been given on the day
delivered, if personally delivered, or on the third business day after the date
of mailing, if mailed.

                  To the Company:

                           Mpower Communications Corp.
                           175 Sully's Trail, Suite 300
                           Pittsford, NY  14534

                           Attention:  Russell I. Zuckerman, Esq.

                  To Executive, at the address provided by him.

                  8. DISPUTE RESOLUTION PROCESS.

                  8.01 NEGOTIATION. (a) Executive and the Company shall attempt
in good faith to resolve any controversy, claim or dispute of whatever nature
arising in connection with the Agreement or the employment relationship
generally, including but not limited to those arising out of or relating to
performance, valuation, breach, termination, enforceability or validity thereof,
whether such claim is based on rights, privileges or interests recognized by or
based upon statute, contract, tort, common law or otherwise (a "DISPUTE"),
promptly by negotiation between Executive and the Company or such person or
group of persons as the Company may designate. For purposes of this Section 8
only, the term "COMPANY" shall be deemed to mean the Company or its designee(s).

                  (b) Executive must provide the Company with a written notice
(a "DISPUTE NOTICE") of any Dispute which has not been resolved in the normal
course of business. Within 15 business days after delivery of the Dispute
Notice, the Company shall submit to Executive a written response (the
"RESPONSE"). The Dispute Notice shall include a statement setting forth the
position of Executive and a summary of arguments supporting such position. The
Response shall include the Company's position with respect to the Dispute and a
summary of the arguments supporting such position. Within 60 business days after
delivery of the Dispute Notice, the Company, and Executive shall meet at a
mutually acceptable time and place, and thereafter as often as they reasonably
deem necessary, to attempt to resolve the Dispute.

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                  (c) If the Dispute has not been resolved within 90 business
days after delivery of the Dispute Notice, or if Executive and the Company, or
its designee, fail to meet within 60 business days after delivery of the Dispute
Notice as provided above, either party may initiate mediation of the Dispute as
hereinafter provided.

                  (d) All negotiations pursuant to this Section 8.01 shall be
treated as compromise and settlement negotiations. Nothing said or disclosed,
nor any document produced, in the course of such negotiations which is not
otherwise independently discoverable shall be offered or received as evidence or
used for impeachment or for any other purpose in any current or future
arbitration or litigation.

                  8.02 MEDIATION. (a) If the Dispute has not been resolved by
negotiation as described above, Executive shall make a good faith attempt to
settle the Dispute by mediation pursuant to the provisions of this Section 8.02
before resorting to arbitration pursuant to Section 8.03 hereof.

                  (b) Unless the parties to the Dispute agree otherwise, the
mediation shall be conducted in accordance with the CPR Institute for Dispute
Resolution Model Procedure for Mediation of Business Disputes then in effect by
a mediator chosen in good faith by the Company.

                  (c) Unless the parties to the Dispute agree otherwise, the
mediator shall be a neutral and impartial lawyer with excellent academic and
professional credentials who has had both training and experience as a mediator
of disputes.

                  (d) Executive may initiate mediation of the Dispute by giving
the Company written notice (a "MEDIATION NOTICE"). Within 15 business days after
the delivery of the Mediation Notice, the Company shall notify Executive of its
choice of the mediator.

                  (e) Within 30 business days after the mediator has been
selected as provided above, Executive and the Company and their respective
attorneys shall meet with the mediator for one or more mediation sessions of at
least four hours cumulatively. If the Dispute cannot be settled at such
mediation sessions or at any mutually agreed continuation thereof, either party
may give the other and the mediator a written notice declaring the mediation
process at an end, in which event then the Dispute shall be resolved by
arbitration as hereinafter provided.

                  (f) All conferences and discussions which occur in connection
with the mediation conducted pursuant to the Plan shall be deemed settlement
discussions, and nothing said or disclosed, nor any document produced, which is
not otherwise independently admissible or discoverable shall be offered or
received as evidence or used for impeachment or for any other purpose in any
current or future arbitration or litigation.

                  (g) The provisions of this Section 8.02 may be enforced by any
court of competent jurisdiction, and the party seeking enforcement shall be
entitled to all costs and expenses, including reasonable attorneys' fees, to be
paid by the party against whom enforcement is ordered.

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                  (h) Except as provided in Section 8.02(g) above, the costs of
the mediation shall be paid by the Company.

                  8.03 ARBITRATION. (a) If the Dispute has not been resolved by
negotiation as provided in Section 8.01 or mediation as provided in Section 8.02
then, the Dispute shall be determined by arbitration in Rochester, New York in
accordance with the Commercial Arbitration Rules of the American Arbitration
Association ("AAA") then in effect by a panel of three arbitrators who (A) have
the qualifications and experience set forth in Section 8.03(b) and (B) are
selected as provided in Section 8.03(c). Any issue as to whether or the extent
to which the Dispute is subject to the arbitration and other dispute resolution
provisions contained in this Agreement, including but not limited to issues
relating to the validity or enforceability of these arbitration provisions, the
applicability of any statute of limitations or other defense relating to the
timeliness of the assertion of any claim or any other matter relating to the
arbitrability of such claim, shall be decided by the arbitrators. The
arbitrators shall base their award on the terms of the Agreement, and the
arbitrators shall strictly follow the law and judicial precedents which a United
States District Judge sitting in the Western District of the State of New York
would apply in the event the Dispute were litigated in such court. The
arbitrators shall render their decision in writing and, unless both parties
agree otherwise, shall include an explanation of the reasons for the award,
which explanation shall be limited to the extent necessary to support the award
and need not attempt to cover all issues raised by the parties. The arbitration
shall be governed by the substantive laws of New York State applicable to
contracts made and to be performed therein, without regard to conflicts of law
rules, and by the arbitration law chosen by the arbitrators, and the arbitrator
shall have no power or authority to order or grant any remedy or relief that a
court could not order or grant under applicable law. Judgment upon the award
rendered by the arbitrators may be entered in any court having jurisdiction
thereof.
                  (b) Every person named on all lists of potential arbitrators
shall be neutral and impartial with excellent academic and professional
credentials (A) with experience in the subject matter of the Dispute and (B) who
has had both training and experience as an arbitrator and is generally available
to serve as an arbitrator.

                  (c) The arbitrators shall be selected as provided in this
Section 8.03(c) and otherwise in accordance with the AAA's Commercial
Arbitration Rules then in effect, except that each party shall be entitled to
strike on a peremptory basis, for any reason or no reason, any or all of the
names of potential arbitrators on any list submitted to the parties by the AAA
as well as any person selected by the AAA to serve as an arbitrator by
administrative appointment. In the event the parties cannot agree on the
selection of the arbitrator, a neutral third-party who shall be mutually agreed
upon by Executive and the Company shall nominate five persons who in his or her
opinion, meet the criteria set forth in Section 8.03(b) which nominees may not
include persons named on any list submitted by the AAA. Each party shall be
entitled to strike one of such five nominees on a peremptory basis and any other
nominees for cause within 10 business days after its receipt of such list of
nominees indicating its order of preference with respect to the remaining
nominees. If two of such nominees have been stricken by the parties, the
unstricken nominees shall be the arbitrators. If less than two nominees are
stricken by the parties, the Company shall choose the arbitral panel from among
the remaining choices. This process shall be repeated until a panel of three
arbitrators has been chosen.

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                  (d) The provisions of this Section 8.03 may be enforced by any
court of competent jurisdiction, and the party seeking enforcement shall be
entitled to all costs and expenses, including reasonable attorneys' fees, to be
paid by the party against whom enforcement is ordered.

                  (e) The costs and fees of the arbitration will be divided
equitably by the arbitrator between the parties; PROVIDED, HOWEVER, that in the
event that either party prevails over the other party in connection with an
arbitration arising out of the breach of this Agreement, the non-prevailing
party shall be liable for all reasonable attorney's fees and expenses incurred
in connection with any action for damages or the enforcement of any provision of
this Agreement brought by the other party.

                  9. MISCELLANEOUS.

                  9.01 NO RIGHTS TO CONTINUED EMPLOYMENT. Neither this Agreement
nor any of the rights or benefits evidenced hereby shall confer upon Executive
any right to continuance of employment by the Company or interfere in any way
with the right of the Company to terminate Executive's employment, subject to
the provisions of Section 4 above, for any reason, with or without Cause.

                  9.02 SOURCE OF PAYMENTS. All payments provided under this
Agreement (other than payments made pursuant to a plan which provides otherwise
or as otherwise expressly provided hereunder) shall be paid in cash from the
general funds of the Company, and no special or separate fund shall be
established, and no other segregation of assets made, to assure payment.
Executive will have no right, title or interest whatsoever in or to any
investments which the Company may make to aid it in meeting its obligations
hereunder. To the extent that any person acquires a right to receive payments
from the Company hereunder, such right shall be no greater than the right of an
unsecured creditor of the Company.

                  9.03 EXECUTIVE'S REPRESENTATION. Executive hereby represent
and warrant to the Company that the execution and delivery by Executive of this
Agreement to the Company will not breach the terms of any contract, agreement or
understanding to which Executive is party. Executive further acknowledges and
agrees that a breach of this representation by Executive shall render this
Agreement void ab initio and of no further force and effect.

                  9.04 SUCCESSORS. This Agreement shall be binding upon and
inure to the benefit of and be enforceable by the parties hereto and their
respective heirs, legal representatives, successors and, in the case of the
Company, business successors (whether direct or indirect, by purchase, merger,
consolidation or otherwise), but no other person shall acquire or have any
rights under or by virtue of this Agreement, and the obligations of Executive
under this Agreement may not be assigned or delegated.

                  9.05 SEVERABILITY. Whenever possible, each provision of this
Agreement will be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement is held to be invalid,
illegal or unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect
any other provision or any other jurisdiction, but this Agreement will be
reformed,


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construed and enforced in such jurisdiction as if such invalid, illegal or
unenforceable provision had never been contained herein.

                  9.06 WITHHOLDING. Amounts paid to Executive's hereunder shall
be subject to all applicable federal, state and local tax withholdings.

                  9.07 TAX STATUS. The parties acknowledge that notwithstanding
the terms of the Executive's share option agreements, the terms of this
Agreement and the nature of the Executive's continuing obligations to the
Company may cause all or a portion of the Executive's options to lose their
status as qualified incentive stock options under the Internal Revenue Code, and
all tax consequences of such modifications shall be the sole responsibility of
the Executive and not of the Company.

                  9.08 HEADINGS. The headings contained in this Agreement are
intended solely for convenience of reference and shall not affect the rights of
the parties to this Agreement.

                  9.09 SURVIVAL. All of the provisions and restrictions set
forth in Section 5 shall survive and continue in full force in accordance with
their terms notwithstanding any termination of the Term.

                  9.10 COUNTERPARTS. This Agreement may be executed in separate
counterparts, each of which is deemed to be an original and all of which taken
together constitute one and the same agreement.

                  9.11 GOVERNING LAW. This Agreement shall be governed by and
construed and enforced in accordance with the laws and decisions of the State of
New York applicable to contracts made and to be performed therein without giving
effect to the principles of conflict of laws.

                  9.12 ENTIRE AGREEMENT; MODIFICATION; WAIVER; INTERPRETATION.
This Agreement contains the entire agreement and understanding between the
parties with respect to the subject matter hereof and supersedes all prior
negotiations and oral understandings, if any, including, without limitation, any
prior agreements between Executive and Primary Network. Neither this Agreement
nor any of its provisions may be modified, amended, waived, discharged or
terminated, in whole or in part, except in writing signed by the party to be
charged. No waiver of any such provision or any breach of or default under this
Agreement shall be deemed or shall constitute a waiver of any other provision,
breach or default. All pronouns and words used in this Agreement shall be read
in the appropriate number and gender, the masculine, feminine and neuter shall
be interpreted interchangeably and the singular shall include the plural and
vice versa, as the circumstances may require.



         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
the date first above written.


                                                     MPOWER COMMUNICATIONS CORP.

                                       11
<PAGE>   12
                                             By: _______________________________
                                                 Name:
                                                 Title:


                                                  ______________________________
                                                   Kent F. Heyman

                                       12
<PAGE>   13
                                   APPENDIX A

                                  KENT KEYMAN

                                EXISTING OPTIONS

<TABLE>
<S>            <C>                 <C>                 <C>          <C>
GRANT          EXPIRATION          GRANT               OPTION       OPTIONS
DATE           DATE                TYPE                PRICE        OUTSTANDING

6/1/96         6/1/06              Incentive           $1.11        28,800
9/4/98         9/4/08              Non-Qualified       $5.33         1,800
9/4/98         9/4/08              Incentive           $5.33         7,200
9/14/00        9/14/10             Incentive           $8.70        40,812
9/14/00        9/14/10             Non-Qualified       $8.70        71,688
</TABLE>

TOTAL OPTIONS OUTSTANDING                                          150,300
<PAGE>   14
                                   APPENDIX B




Mpower Communications Corp.
175 Sully's Trail, Suite 300
Pittsford, NY 14534

                                     RELEASE


                  I, [NAME], am a party to an Employment Agreement
("AGREEMENT"), dated April 16, 2000, with Mpower Communications Corp, a Nevada
corporation (the "COMPANY"). The Agreement contemplates that, on the Termination
Date (as such term is defined in the Agreement), I will deliver a Release in the
form set forth below, and I now desire to deliver such Release to the Company in
the manner contemplated by the Agreement.

                  1. General Release. In consideration of the obligations and
payments provided to me under Section 4 of the Agreement, I hereby release and
forever discharge the Company and its employees, officers and directors from any
and all claims, actions and causes of action (collectively, "CLAIMS"),
including, without limitation, any Claims arising under any applicable federal,
state or local law, or any law of any foreign jurisdiction, that I may have, or
in the future may possess, arising out of (i) my employment relationship with
and service as an employee, officer or director of any of the Company , and the
termination of such relationship or service, or (ii) any event, condition,
circumstance or obligation that occurred, existed or arose on or prior to the
date hereof. I further agree that the payments and benefits described in the
Agreement are in full satisfaction of any and all claims for payments or
benefits that I may have against the Company arising out of my employment
relationship, my service as an employee, officer or director of the Company and
the termination thereof.

                  2. Specific Release of ADEA Claims. In consideration of the
payments and benefits provided to me under Section 4 of the Agreement, I hereby
release and forever discharge the Company and its employees, officers and
directors from any and all Claims that I may have as of the date of my signing
of this Release arising under the FEDERAL AGE DISCRIMINATION IN EMPLOYMENT ACT
OF 1967, AS AMENDED, and the applicable rules and regulations promulgated
thereunder ("ADEA").

                  3. Release of Unknown Claims. I understand that I am releasing
Claims under Section 1 that I may not know about, and that is my intent. I
expressly waive all rights that I might have under any law that is intended to
prevent unknown Claims from being released and I understand the significance of
doing so. In addition, I expressly acknowledge that the Release under Section 1
is intended to include and does include in its effect, without limitation, all
Claims which I do not know or suspect to exist in my favor at the time of
execution of this Release and that this Release expressly contemplates the
extinguishment of all such Claims.

                  4. Representation. I hereby represent and agree that I have
not filed, and will not file, any action, complaint, charge, grievance or
arbitration against any of the Company or any of their respective employees,
officers, directors or agents.

                  5. Acknowledgment. By signing this Release, I hereby
acknowledge and confirm the following:

             (a) Consultation with an Attorney. I was advised in writing by the
       Company in connection with my resignation to consult with an attorney of
       my choice prior to signing the Agreement and this Release and to have
       such attorney explain to me the terms of the Agreement and this Release,
       including, without limitation, the terms relating to my release of claims
       arising under ADEA.

             (b) Understand this Agreement. I have read the Agreement and this
       Release carefully and completely and understand each of the terms
       thereof.

                                       13
<PAGE>   15
             (c) Twenty-One Days to Consider. I was given not less than
       twenty-one days to consider the terms of the Agreement and this Release
       and to consult with an attorney of my choosing with respect thereto, and
       that for a period of seven days following my signing of this Release, I
       have the option to revoke this Release in accordance with the terms set
       forth below.

             (d) Consideration. By signing this Release, I hereby acknowledge
       and confirm that I am providing the Release and discharge set forth
       herein only in exchange for consideration in addition to anything of
       value to which I am already entitled.

       6. Revocation. I have the right to revoke this Release during the
seven-day period (the "REVOCATION PERIOD") commencing immediately following the
date I sign and deliver this Release to the Company . The Revocation Period
shall expire at 5:00 p.m., New York time, on the last day of the Revocation
Period; PROVIDED, HOWEVER, that if such seventh day is not a business day, the
Revocation Period shall extend to 5:00 p.m. on the next succeeding business day.
In the event of any such revocation by me, the obligations of the Company to
make the payments contemplated by Section 4 of the Agreement shall terminate and
be of no further force and effect as of the date of such revocation. No such
revocation by me shall be effective unless it is in writing and signed by me and
received by a representative of the Company prior to the expiration of the
Revocation Period.


       My signature below indicates my agreement with the terms and provisions
described above.

       ____________________________                  [NAME]

                                                  ____________________________
                                                  Date


                                       14