EMPLOYMENT AGREEMENT


     THIS EMPLOYMENT AGREEMENT  ("Agreement") is made as of the 19th day of May,
1999 by and between ICG Communications,  Inc.  ("Employer" or the "Company") and
Harry R. Herbst ("Employee").

                                 R E C I T A L S

     WHEREAS, the Company desires to employ Employee as provided herein; and

     WHEREAS, Employee desires to be employed by Employer as provided herein.

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

     1.  Employment.  The Company agrees to employ  Employee and Employee hereby
agrees to be  employed  on a  full-time  basis by the  Company or by such of its
subsidiary  or  affiliate  corporations  as  determined  by the  Company in such
position as is mutually agreed, for the period and upon the terms and conditions
hereinafter set forth.

     2.  Duties.  During his employment,  Employee  shall perform the duties and
bear the  responsibilities  commensurate  with his  position and shall serve the
Employer  faithfully and to the best of his ability.  Employee shall devote 100%
of his working time to carrying out his obligations hereunder.

     3.  Compensation and Benefits.

     3.1 The Company  shall pay  Employee  during the Term of this  Agreement an
annual base salary, payable semi-monthly.  The annual base salary will initially
be Three Hundred Two Thousand Five Hundred Dollars ($302,500).

     3.2 In addition to the base salary, Employee will be eligible for an annual
performance  bonus in an exact amount to be determined by the Board of Directors
of the Company or the Compensation Committee of the Board. The annual bonus will
be determined in accordance with the bonus plan of the Company and will be based
on objectives and goals set for the Company and the Employee.  Employee's annual
bonus is initially  established  at 50% of annual base salary if all  objectives
and goals are met.

     3.3 In addition to salary and bonus payments as provided above, the Company
will provide Employee,  during the Term of this Agreement,  with the benefits of
such insurance plans,  hospitalization  plans and other  perquisites as shall be
generally  provided  to  employees  of the  Company  at his  level and for which
Employee may be eligible under the terms and conditions  thereof.  Employee will
also be entitled to all  benefits  provided  under any  directors  and  officers


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liability insurance or errors and omissions insurance maintained by the Company.
Throughout the Term of this Agreement,  the Company will provide Employee with a
car allowance in the amount of Seven Hundred Dollars ($700) per month.

     3.4  Throughout  the Term of this  Agreement,  the Company  will  reimburse
Employee  for all  reasonable  out-of-pocket  expenses  incurred  by Employee in
connection  with the business of the Company and the  performance  of his duties
under  this  Agreement,  upon  presentation  to the  Company by  Employee  of an
itemized  accounting of such expenses with  reasonable  supporting  data. At the
request of Employee, the Company will during the Term of this Agreement purchase
and maintain at the expense of the Company a life  insurance  policy on the life
of the  Employee  with the  beneficiary  being the estate of the  Employee in an
amount  equal to two (2) times the  aggregate  amount of his annual  base salary
plus his targeted annual bonus.

     3.5 The Company  will from time to time provide to Employee  stock  options
pursuant  to and  subject to the terms and  conditions  of the  Company's  Stock
Option Plans.

     4. Term.  The initial  term of this  Agreement  will be for three (3) years
commencing  as of the date  hereof  ("Term").  After  one (1) year from the date
hereof,  this Agreement will thereafter  automatically renew from month-to-month
such that there will always be two (2) years  remaining in the Term,  unless and
until  either  party  shall give at least sixty (60) days notice to the other of
his or its desire to terminate  this Agreement (in such case, the Term shall end
upon the date indicated in such notice).  The applicable  provisions of Sections
6, 7, and 8 shall remain in full force and effect for the time periods specified
in such Sections notwithstanding the termination of this Agreement.

     5. Termination.

     5.1 If Employee dies during the Term of this Agreement, this Agreement will
terminate.  The Company will pay the estate of Employee an amount equal to three
months salary. In addition,  the estate of Employee will be entitled to exercise
all options  theretofore  vested  under the  Company's  Stock Option Plans for a
period of one (1) year after the date of death of  Employee in  accordance  with
the plans and agreements relating to such options.

     5.2 If,  during the Term of this  Agreement,  Employee  is  prevented  from
performing  his duties by reason of illness or incapacity  for one hundred forty
(140) days in any one hundred eighty (180) day period, the Company may terminate
this  Agreement,  upon thirty (30) days notice to Employee or his duly appointed
legal  representative.  Employee will be entitled to all benefits provided under
any disability plans of the Company. In addition, Employee or his duly appointed
legal representative will be entitled to exercise all options theretofore vested
under the  Company's  Stock  Option Plans for a period of one (1) year after the
date of termination in accordance with the plans and agreements relating to such
options.

     5.3 For the  purposes  of this  Agreement,  a "Change  in  Control"  of the
Company  shall mean and be deemed to have  occurred if (a) any "person" (as such
term is used in Sections 13(d) and 14(d) of the Securities  Exchange Act of 1934
as amended  (Exchange Act)) is or becomes the "beneficial  owner" (as defined in
Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the


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Company  representing  50% or more of the combined voting power of the Company's
then outstanding securities;  (b) at any time a majority of the directors of the
Company are persons who were not  nominated  for election by the Board;  (c) the
stockholders  of the Company  approve a merger or  consolidation  of the Company
with any other  corporation,  other than a merger or  consolidation  which would
result in the voting  securities of the Company  outstanding  immediately  prior
thereto  continuing to represent  (either by remaining  outstanding  or by being
converted  into voting  securities of the surviving  entity) at least 50% of the
combined voting power of the voting  securities of the Company or such surviving
entity  outstanding  immediately  after such  merger or  consolidation;  (d) the
Company shall sell or otherwise  dispose of, in one  transaction  or a series of
related  transactions,  assets  aggregating  more than 50% of the  assets of the
Company  and  its  subsidiaries  consolidated;  or (e) the  stockholders  of the
Company  approve a plan of complete  liquidation of the Company or any agreement
for the sale or  disposition  by the  Company  of all or  substantially  all the
Company's assets. Upon the occurrence of a Change in Control,  the Company shall
pay Employee an amount equal to one (1) times the aggregate amount of his annual
base salary plus his targeted annual bonus plus the annual value of his benefits
and  perquisites.  At the time of the  occurrence  of a Change  in  Control  all
options to  purchase  shares of the Company  that have been  granted to Employee
pursuant  to the  Company's  Stock  Option  Plans,  but  not  yet  vested,  will
immediately  vest and  Employee  shall be entitled to exercise  such  options in
accordance with the plans and agreements  relating to such options. In addition,
the Company or Employee may terminate  this  Agreement upon at least thirty (30)
days notice at any time within one (1) year after the  occurrence of a Change in
Control of the Company.

     5.4 Employee may terminate  this  Agreement  upon at least thirty (30) days
notice upon the  occurrence  of a  constructive  dismissal of Employee.  For the
purposes of this Agreement,  "constructive dismissal" includes, without limiting
the  generality  of any action by the  Company  which  constitutes  constructive
dismissal,  unless  consented  to by Employee in writing,  any of the  following
actions by the Company:

          (i)  any  material   reduction  in   Employee's   positions,   duties,
               responsibilities, powers or reporting relationships;

          (ii) any reduction in the annual salary of Employee;

          (iii)any  requirement  to relocate to another city,  state or country;
               and

          (iv) any material reduction in the value of Employee's  benefits plans
               and programs,  including,  without limiting the generality of the
               foregoing, bonus arrangements.

     5.5  The  Company  may  terminate  this  Agreement  immediately  for  gross
negligence,  intentional  misconduct  or  the  commission  of a  felony  by  the
Employee, in which case all rights under this Agreement shall end as of the date
of such termination.

     5.6  If this Agreement  is  terminated  by the Company  under  Section 4 or
Section 5.3, the Company shall pay Employee a termination fee in an amount equal
to three (3) times the  aggregate  amount of his  annual  base  salary  plus his
targeted  annual bonus plus the annual  value of his  benefits and  perquisites.


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Such  termination  fee will be paid in a lump sum within  fifteen (15) days from
the date of  termination.  If this  Agreement is  terminated  by Employee  under
Section 5.3 or Section  5.4, the Company  will pay  Employee a  termination  fee
equal to three (3) times the aggregate amount of his annual base salary plus his
targeted  annual bonus plus the annual  value of his  benefits and  perquisites.
Such  termination  fee will be paid in a lump sum within  fifteen (15) days from
the date of termination.  In addition,  if the Company terminates this Agreement
under  Section 4 or Employee  terminates  this  Agreement  under  Section 5.3 or
Section  5.4,  all  options to  purchase  shares of the  Company  that have been
granted to Employee  pursuant to the Company's  Stock Option Plans,  but not yet
vested,  will  immediately  vest on the date of termination and Employee will be
entitled to exercise  all options  held by the  Employee for a period of six (6)
months after the date of termination in accordance with the plans and agreements
relating to such options.

     6. Non-Compete and Non-Interference.

     6.1 During the Term of this  Agreement and, if Employee's  employment  with
the Company is terminated under Section 4 or Section 5.3, for a period of twelve
(12) months after such termination,  Employee shall not, directly or indirectly,
own, manage, operate,  control, be employed by, or participate in the ownership,
management,  operation  or control  of, a  business  that is engaged in the same
business  as the  Company  within  any  area  constituting,  during  the term of
Employee's  employment or at the time  Employee's  employment is  terminated,  a
Relevant  Area.  A "Relevant  Area"  shall be defined  for the  purposes of this
Agreement as any area located  within,  or within fifty (50) miles of, the legal
boundaries or limits of any city within which the Company is engaged in business
or in which the  Company  has  publicly  announced  or  privately  disclosed  to
Employee that it plans to engage in business.

     6.2 During the Term of this  Agreement  and for a  period  of two (2) years
after  termination  of  this  Agreement,  Employee  shall  not (i)  directly  or
indirectly  cause or attempt to cause any  employee of the Company or any of its
affiliates to leave the employ of the Company or any affiliate,  (ii) in any way
interfere with the relationship  between the Company and any employee or between
an affiliate and any employee of the affiliate, or (iii) interfere or attempt to
interfere with any transaction in which the Company or any of its affiliates was
involved during the Term of this Agreement.

     6.3 Employee  agrees  that,  because of the nature and  sensitivity  of the
information to which he will be privy and because of the nature and scope of the
Company's  business,  the restrictions  contained in this Section 6 are fair and
reasonable.


     7. Confidential Information.

     7.1 The relationship  between the Company and Employee is one of confidence
and trust.  This  relationship and the rights granted and duties imposed by this
Section  shall  continue  until a date ten (10) years  from the date  Employee's
employment is terminated.

     7.2  As  used  in  this  Agreement  (i)  "Confidential  Information"  means
information  disclosed  to or acquired by Employee  about the  Company's  plans,


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products,  processes and services,  including  information relating to research,
development,  inventions,  manufacturing,  purchasing, accounting,  engineering,
marketing,  merchandising,  selling,  pricing,  tariffed or  contractual  terms,
customer lists and prospect lists and other market information,  with respect to
any of the  Company's  business  activities;  and (ii)  "Inventions"  means  any
inventions,   discoveries,  concepts  and  ideas,  whether  patentable  or  not,
including, without limitation,  processes, methods, formulas, and techniques (as
well as  related  improvements  and  knowledge)  that are based on or related to
Confidential   Information,   that  pertain  in  any  manner  to  the  Company's
technology,  expertise  or business  and that are made or conceived by Employee,
either  solely or jointly  with  others,  and while  employed  by the Company or
within  six (6)  months  thereafter,  whether  or not made or  conceived  during
working  hours  or  with  the  use of the  Company's  facilities,  materials  or
personnel.

     7.3  Employee  agrees  that he  shall  at no time  during  the Term of this
Agreement or at any time thereafter disclose any Confidential Information to any
person,  firm or  corporation  to any extent or for any reason or purpose or use
any  Confidential  Information  for any  purpose  other than the  conduct of the
Company's business.

     7.4 Any Confidential Information that is directly or indirectly originated,
developed  or  perfected  to any  degree  by  Employee  during  the  term of his
employment  by the Company  shall be and remain the sole property of the Company
and shall be deemed trade secrets of the Company.

     7.5  Upon  termination  of  Employee's  employment  pursuant  to any of the
provisions  herein,  Employee or his legal  representative  shall deliver to the
Company  all  originals  and all  duplicates  and/or  copies  of all  documents,
records,  notebooks,  and similar  repositories  of or  containing  Confidential
Information then in his possession, whether prepared by him or not.

     7.6  Employee  agrees that the covenants and  agreements  contained in this
Section 7 are fair and  reasonable  and that no waiver or  modification  of this
Section or any covenant or condition  set forth herein shall be valid unless set
forth in writing and duly executed by the parties hereto.

     8. Injunctive Relief.  Upon a material breach or threatened material breach
by Employee of any of the provisions of Sections 6 or 7 of this  Agreement,  the
Company  shall be  entitled  to an  injunction  restraining  Employee  from such
breach.  Nothing  herein  shall be  construed  as  prohibiting  the Company from
pursuing any other  remedies  for such breach or  threatened  breach,  including
recovery of damages from Employee.

     9. No Waiver.  A waiver by the Company of a breach of any provision of this
Agreement  by  Employee  shall not  operate or be  construed  as a waiver of any
subsequent or other breach by Employee.

     10. Severability.  It is the  desire  and  intent of the  parties  that the
provisions of this Agreement shall be enforced to the fullest extent permissible
under  the  laws and  public  policies  applied  in each  jurisdiction  in which
enforcement is sought.  Accordingly,  if any particular  provision or portion of
this  Agreement  shall be  adjudicated  to be  invalid  or  unenforceable,  this

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Agreement  shall  be  deemed  amended  to  delete  therefrom  the  portion  thus
adjudicated  to be invalid or  unenforceable,  such  deletion to apply only with
respect to the operation of such  provision in the  particular  jurisdiction  in
which such adjudication is made.

     11. Notices.  All  communications,  requests,  consents  and other  notices
provided for in this Agreement  shall be in writing and shall be deemed given if
delivered by hand or mailed by first class mail,  postage  prepaid,  to the last
known address of the recipient.

     12. Governing Law. This  Agreement  shall be  governed by and construed and
enforced in accordance with the laws of the State of Colorado.

     13. Assignment.  Neither  this Agreement nor any rights or duties hereunder
may be assigned by Employee or the Company  without the prior written consent of
the other, such consent not to be unreasonably withheld.

     14. Amendments.  No provision of this Agreement shall be altered,  amended,
revoked or waived except by an  instrument  in writing,  signed by each party to
this Agreement.

     15. Binding Effect.  Except as otherwise  provided  herein,  this Agreement
shall be binding  upon and shall inure to the benefit of the parties  hereto and
their respective legal representatives, heirs, successors and assigns.

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

     17. Entire  Agreement.  This Agreement sets forth the entire  agreement and
understanding of the parties and supersedes all prior understandings, agreements
or  representations  by or between the parties,  whether written or oral,  which
relate in any way to the subject matter hereof.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.
                                          /s/ Harry R. Herbst
                                          --------------------------------------
                                          Harry R. Herbst


                                          ICG COMMUNICATIONS, INC.


                                          By:     /s/ J. Shelby Bryan
                                                  ------------------------------

                                          Name:   J. Shelby Bryan
                                                  ------------------------------

                                          Title:  President and CEO
                                                  ------------------------------

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