EMPLOYMENT AGREEMENT

         THIS EMPLOYMENT AGREEMENT (the "Agreement") is made and entered into as
of  the  4th  day  of  December,  1998,  by and  between  Savvis  Communications
Corporation (the "Employer") and Clyde A. Heintzelman (the "Executive").

                                   WITNESSETH:

         WHEREAS:

         (1) Employer desires to retain Executive's services, upon the terms and
conditions hereafter described, and Executive desires to be employed by Employer
upon such terms and conditions;

         (2) Executive understands and acknowledges that in connection with this
proposed employment Executive will meet important customers and referral sources
of  Employer,  and learn of  confidential  business  information,  ways of doing
business,  and trade secrets of Employer of which  Executive was not aware,  and
that accordingly  Executive's agreement to and compliance with the covenants and
terms  set  forth in  Sections  7 and 8 of this  Agreement  are a  material  and
essential condition to Employer's agreement to employ Executive;

         NOW,  THEREFORE,  in consideration  of the premises,  and the promises,
covenants and agreements hereinafter described,  Employer and Executive agree as
follows:

         1. Employment.  Employer hereby employs Executive, and Executive hereby
accepts  employment with Employer,  upon and subject to the terms and conditions
set forth in this  Agreement.  Employer  shall at all times  during  Executive's
employment  nominate  Executive for a seat on Employer's  Board of Directors and
use its reasonable efforts to cause Executive to be elected to the Board.

         2. Duties.  Executive  shall serve as the President and Chief Executive
Officer of Employer,  and perform,  under and according to Employer's  direction
and control and to the best of Executive's abilities,  all executive,  advisory,
administrative,  and/or  managerial  duties  (if any) which may be  assigned  or
delegated to  Executive  from time to time by the Board of Directors of Employer
or the Chairman of the Board of directors  ("Chairman").  Executive  shall carry
out, follow and comply with all directives,  rules, and policies of Employer and
the  Board  and  Chairman,   shall  have  the  authority  and   responsibilities
customarily exercised by a President and Chief Executive Officer, subject to the
Board's direction and control, and without additional compensation shall provide
services  to,  and serve as an  officer  and/or  director  of,  any  subsidiary,
affiliate or other  business or venture in which  Employer may hold an interest,
as the Board of Directors may direct.

<PAGE>


Executive  also  shall  be  responsible  for  operating  Employer  at a level of
profitability  and financial  performance  established  by  Employer's  Board of
Directors from time to time.  Executive shall consult with  Employer's  Board of
Directors and the Chairman, as requested by such Board from time to time, on all
manners including without limitation the development of an annual budget.

         Executive shall exert  Executive best efforts and devote  substantially
all of Executive's  working time,  attention and energies to Employer's business
and the  performance  of  Executive  duties,  and shall not  engage in any other
business  activity,  whether or not such  employment  or  business  activity  is
pursued  for  gain,  profit or other  pecuniary  advantage,  without  Employer's
express prior written consent;  provided,  however, that (1) Executive may serve
on the Board of Directors of another  corporation  provided such  activities and
service do not violate any other covenant or term of this  Agreement,  interfere
with the performance of Executive's duties for Employer, or create a conflict of
interest or the  appearance  of a conflict of interest with respect to Employer;
(2) if the same does not violate any other  covenant or term of this  Agreement,
Executive may invest  Executive's  personal assets in any form or manner so long
as it does not require  Executive's  services or advice in the  operation of any
business in which such  investment is made (but nothing in this Agreement  shall
restrict  Executive's  right to  invest  in  Employer  or the  Company  (defined
below)).

         3.       Term of Employment.

                  (a) Executive's  employment with Employer  commences as of the
date  first  written  above,  and  unless  earlier  terminated  pursuant  to the
provisions of Section  3(b),  terminates at the close of business on December 3,
2000 (the "Term"),  provided,  however, that commencing on December 2, 2000, and
on each annual  anniversary of such date (such date and each annual  anniversary
being called a "Renewal Date"), this Agreement automatically shall extend for an
additional one-year period upon the terms described in this paragraph, unless 60
days or more prior to the Renewal  Date,  either party gives notice to the other
in accordance with Section 14 that such party elects not to renew the employment
term. If such notice of non-renewal is given, then Executive's  employment shall
terminate at the  expiration  of the then current term. In the case of each such
renewal (i) Executive shall be compensated as set out in Section  4(a)-(b);  and
(ii) all other terms of this Agreement (including those respecting  termination)
shall remain in full force and effect. The parties  acknowledge their intentions
that the foregoing  provisions  could (through the failure to elect not to renew
or to exercise  rights  under  Section  3(b))  result in a perpetual  employment
without any definite duration during Executive's life.

                  (b) Notwithstanding the foregoing,  prior to the expiration of
the Term (as the same may be extended)  (i) Employer may  terminate  Executive's
employment,  without  prior  notice,  "Cause"  (meaning  Executive's  failure or
refusal

                                      -2-
<PAGE>

to perform any stated duty,  misconduct or dishonesty by Executive in connection
with the  performance  of this  Agreement  or any  other of  Executive's  duties
hereunder, disloyalty, misappropriation of funds by Executive, Executive's being
convicted of any crime constituting a felony, fraudulent or unethical conduct by
Executive related to or affecting Executive's  employment,  failure of Executive
to meet or achieve  specific  business  plans or objectives as determined by the
Board of  Directors  of  Employer  and which have been made  known to  Executive
(which is not remedied  within 10 days after written notice of the same is given
by  Employer),  or any other  breach of this  Agreement  (which is not  remedied
within 10 days  after  written  notice of the same is given by  Employer);  (ii)
Executive's  employment  terminates  immediately upon Executive's  death;  (iii)
Executive's  employment  may be  terminated,  at Employer's  option,  if, due to
physical or mental illness,  injury, or condition Executive is unable to perform
any essential function of Executive's position with reasonable accommodation for
a period of more than 90  consecutive  days;  (iv)  Executive  may terminate his
employment  for  "Good  Reason"  (meaning  (x) any  violation  of a term of this
Agreement by Employer which is not remedied  within 10 days after written notice
of the same is given by  Executive,  (y) the  assignment  of Executive to duties
which result in a substantial  diminution  of  Executive's  position,  duties or
responsibilities  as provided for in this  Agreement  (excluding an isolated and
inadvertent  action which is remedied by Employer  within 10 days after  written
notice of the same is given by Executive or a temporary or occasional assignment
by the Board or the Chairman made for reasons of business  necessity in the good
faith  judgment  of the  Board  of its  Chairman),  or (z)  without  Executive's
consent,  relocation  of  Executive  from  Employer's  corporate  offices  to be
established  in the Reston,  Virginia area, or the closing or relocation of such
corporate offices, in violation of the provisions of Section 5).

                  (c) Upon  termination  of  Executive's  employment  hereunder,
Executive shall be entitled only to receive any compensation  accrued but unpaid
as of such date,  and shall  deliver  to  Employer  all  property  of  Employer.
However,  in the event Executive validly  terminates his employment prior to the
expiration  of the Term for Good  Reason  (as  defined  above),  or  Executive's
employment  is  terminated   pursuant  to  Section  3(b)(ii)  or  (iii),   then,
notwithstanding  the provisions of Section 4(b),  Executive shall be eligible to
receive as and when  described  below,  with respect to the fiscal year in which
employment  terminates,  a pro-rated  portion of the Executive's Bonus under the
bonus plan for Executive in effect for that fiscal year provided the performance
goals for the Bonus plan for the entire  fiscal year are in fact  achieved.  The
pro-rated  portion shall be paid at the same time the Bonus otherwise would have
been payable under the Agreement if Executive had remained in Employer's employ,
and shall be equal to a percentage  of the Bonus equal to the  percentage of the
fiscal year during which Executive was employed by Employer.

                                      -3-
<PAGE>

         If Executive validly terminates  Executive's employment for Good Reason
as described above, or if Employer terminates  Executive's employment (excluding
a  termination  under  Section  3(b)(i),  (ii) or  (iii))  without  cause  or in
violation of this Agreement  prior to the expiration of the Term, then Executive
shall be entitled to receive,  as and when described  below,  an amount equal to
the then current rate of Base Salary being paid to Employer  (excluding bonuses,
benefits,  or other  compensation),  provided  that during the time payments are
being made to Executive, Executive complies with the provisions of Section 7 and
8 whether or not they otherwise would be enforceable,  and provided further that
Executive  first  executes  and  delivers  to  Employer a  document  in form and
substance satisfactory to Employer,  releasing, waiving, and agreeing not to sue
on any claims or causes of action which  Executive then may have or hold against
Employer,  the  Company,  or  any of  their  respective  affiliates,  employees,
directors,  insurors  or  agents  arising  out  of or  relating  to  Executive's
employment,  this Agreement or its termination,  or any facts occurring prior to
that date, and all conditions to making that release and waiver legal  effective
have been satisfied.  This sum will be paid out in 12 equal consecutive  monthly
installments  on the Employer's  regular  monthly  paydays,  commencing with the
month  following  the  month  Executive's  employment  terminates  and all  such
conditions have been  satisfied.  These payments are in addition to any prorated
bonus to which Executive may be entitled under the provisions of the immediately
preceding paragraph.

                  (d) The provisions of Section 3, 7, 8 and 9 of this Agreement,
and any related provisions,  shall survive and continue after the termination of
this Agreement and after the termination of Executive's employment.

         4. Compensation. For the services rendered pursuant to this Agreement's
terms, during Executive's employment (except for any period in excess of 90 days
during which  Executive may be  restricted in performing  duties for Employer by
reason of a Court Order) Executive shall receive the following:

                  (a) Base Salary.  Executive shall be compensated at any annual
rate of $250,000 ("Base Salary"). Payments will be made at least once a month on
a regular payday of Employer.

                  (b)  Bonus.  Executive  shall be  entitled  to receive a bonus
("Bonus"),  payable and  determined  as  described  below,  for each fiscal year
(starting with the 1999 fiscal year) in which  Executive  meets the  performance
goals  established by the Employer's Board of Directors after  consultation with
Executive  for such fiscal  year and was  employed by Employer at the end of the
fiscal year. The Bonus will be paid within thirty (30) days after the Employer's
audited  financial  statements for such fiscal year are issued.  With respect to
any such Bonus plan and goals  established  by  Employer's  Board of  Directors.
Executive  shall be  eligible  to  qualify  for a bonus of at least  25% of Base
Salary,  and the Board of Directors  may  establish

                                      -4-
<PAGE>


a bonus of up to 50% of Base  Salary,  upon  meeting  the  bonus  plan and goals
established by the Board.

                  (c) Review.  Employer will review the compensation spelled out
above, on an annual basis, to determine whether any adjustment more favorable to
Executive should be made. Executive shall be reviewed prior to January 31, 2000.

                  (d)  Withholding.  Employer  shall  withhold from  Executive's
compensation  all amounts owed Employer (if any) and all amounts  required to be
withheld under federal, state or local law.

                  (e)  Benefit  Plans.   During   Executive's   employment  with
Employer,  Employer will pay the cost of Executive's  participation in any group
health  insurance  plan then  maintained by Employer to the same limited  extent
provided to  employees  of  Employer  generally.  Executive  will be entitled to
participate  in any other  benefit  plan of Employer  offered by Employer to its
employees  generally,  provided  Executive is eligible to participate  under the
terms of any such plan at standard rates.

                  (f)  Options.  Executive  shall  be  granted  an  option  (the
"Option")  under the current  Incentive  Stock  Option  Plan of Savvis  Holdings
Corporation  (the  "Company"),  per  the  terms  of the  standard  Stock  Option
Agreement  under  that  Plan (a copy of the form of which is  attached)  and the
Stock  Option  Plan,  as described  below.  The Option will be to purchase  that
number of shares of the  Company's  common stock which  constitute  five percent
(5%) of the current fully diluted  number of all shares of the Company's  common
stock at the price of eighty cents  (80(cent))  per shares,  provided,  however,
that if there is a  closing  of an  equity  financing  involving  the  Company's
current  investors  prior to June 1, 1999,  then with  respect to the first such
equity financing,  Executive's option to purchase shares shall not be diluted by
the amount of equity shares (including any convertible debentures) purchased (or
commuted to be  purchased) by such current  investors in such equity  financing,
and the amount of shares which  Executive  will have an option to purchase under
this  option  shall be  increases  as  calculated  by  Employer so as to provide
Executive  the  option  to  purchase  five  percent  (5%) of the  shares  of the
Corporation after taking into account such equity investment.  This Option shall
be granted  immediately  upon  closing of the next equity  financing  or June 1,
1999,  whichever  first occurs.  To the extent the Option is an incentive  stock
option for federal income tax purposes, the Option shall not be convertible to a
non-qualified stock option without Executive's express consent.  Notwithstanding
anything to the contrary in such Stock Option Plan: (1) one-third of the options
granted pursuant to said option agreement shall vest immediately when the option
is granted and Executive has executed and delivered this Agreement and the Stock
Option  Agreement,  with the balance to vest over a forty-two  (42) month period
1/42  per  month  (subject  to the  terms  of the  Plan  and  the  Stock  Option
Agreement),  and (2) all other of such options shall  immediately  vest upon the
sale of all or

                                      -5-
<PAGE>

substantially  all of the  assets  or stock of  Employer,  or in the  event of a
"Change Of Control" involving Employer (as such term is defined below), provided
Executive then is employed by Employer.  In the event of Executive's  death, the
options granted to Executive may be exercised by his personal  representative to
the extent otherwise  exercisable by Executive under the terms of the applicable
plan and option agreement. Executive must be employed as of June 1, 1999, or the
date the  equity  financing  occurs  (whichever  first  occurs),  in order to be
eligible for this Option;  provided,  however, that if Executive's employment is
terminated  prior to such  date,  Executive  nevertheless  will be  deemed to be
eligible for, and to have vested in, that portion of the Option which  comprises
one-third  (1/3) of the options to which  Executive  would have been entitled if
Executive  had been employed as of June 1, 1999 based upon the amount of Company
common stock currently outstanding.

         For the purpose of this Section 4(f), a "Change of Control" shall mean:

         (A) the  acquisition  by any  individual,  entity or group  [within the
meaning of Section 13(d)(3) or 14(d)(2) of the Securities  Exchange Act of 1934,
as amended (the "Exchange  Act")] (a "Person") of beneficial  ownership  (within
the meaning of Rule 13d-3  promulgated under the Exchange Act) of 50% or more of
either  (i) the then  outstanding  shares  of common  stock of  Savvis  Holdings
Corporation (the "Company") (the "Outstanding Company Common Stock") or (ii) the
combined voting power of the then outstanding  voting  securities of the Company
entitled to vote  generally  in the  election  of  directors  (the  "outstanding
Company  Voting  Securities");  provided,  however,  that for  purposes  of this
subsection  (a),  the  following  acquisition  shall not  constitute a Change of
Control;  (i) any  acquisitions  directly  from the Company  (including  but not
limited to an acquisition of shares from the Company),  (ii) any  acquisition by
the Company,  (iii) any  acquisition  by any  employee  benefit plan (or related
trust)  sponsored or maintained by the Company or any corporation  controlled by
the  Company,  or  (iv)  any  acquisition  by  any  corporation  pursuant  to  a
transaction which complies with clauses (i), (ii) and (iii) of subsection (c) of
this Section; or

         (B) Individuals who, as of the date hereof, constitute the Board of the
Company (the  "Incumbent  Board")  cease for any reason to constitute at least a
majority  of the  Board;  provided,  however,  that any  individual  becoming  a
director  subsequent  to the date  hereof  whose  election,  or  nomination  for
election by the  Company's  shareholders,  was  approved by a vote of at least a
majority  of  the  directors  then  comprising  the  Incumbent  Board  shall  be
considered as though such individual were a member of the Incumbent  Board,  but
excluding,  for this purpose,  any such individual  whose initial  assumption of
office  occurs  as a result of an actual or  threatened  election  contest  with
respect to the election or removal of  directors  or other actual or  threatened
solicitation  of proxies or consents by or on behalf of a Person  other than the
Board; or

                                      -6-
<PAGE>

         (C) Consummation of a  reorganization,  merger or consolidation or sale
or other disposition of all or substantially all of the assets of the Company (a
"Business   Combination"),   in  each  case,  unless,  following  such  Business
Combination,  (i) all or  substantially  all of the individuals and entities who
were the beneficial  owners,  respectively,  of the  Outstanding  Company Common
Stock  and  Outstanding  Company  Voting  Securities  immediately  prior to such
Business Combination beneficially own, directly or indirectly, more than 50% of,
respectively,  the then  outstanding  shares  of common  stock and the  combined
voting  power  of the  then  outstanding  voting  securities  entitled  to  vote
generally in the election of directors,  as the case may be, of the  corporation
resulting  from such Business  Combination  (including,  without  limitation,  a
corporation  which as a result of such  transaction  owns the  Company or all or
substantially all of the Company's assets either directly or through one or more
subsidiaries)  in  substantially   the  same  proportions  as  their  ownership,
immediately prior to such Business Combination of the Outstanding Company Common
Stock and  Outstanding  Company Voting  Securities,  as the case may be, (ii) no
Person  [excluding any corporation  resulting from such Business  Combination or
any employee  benefit plan (or related trust) of the Company or such corporation
resulting  from  such  Business  Combination]  beneficially  owns,  directly  or
indirectly, 50% or more of, respectively,  the then outstanding shares of common
stock  of the  corporation  resulting  from  such  Business  Combination  or the
combined  voting  power  of the  then  outstanding  voting  securities  of  such
corporation  except to the  extent  that  such  ownership  existed  prior to the
Business Combination,  and (iii) at least a majority of the members of the board
of directors of the corporation  resulting from such Business  Combination  were
members  of the  Incumbent  Board at the time of the  execution  of the  initial
agreement,  or  of  the  action  of  the  Board,  providing  for  such  Business
Combination.

                  (h) Automobile Allowance. During his employment with Employer,
Executive shall receive an automobile allowance of $800 per month.

         5. Office.  During Executive's  employment,  unless otherwise agreed by
Executive,  Executive  shall be entitled  to office at, and perform  Executive's
duties  principally out of, a corporate office maintained by Employer in Reston,
Virginia or the immediately surrounding area. Executive shall have the authority
to  determine,  after  consultation  and  review  with the  Employer's  Board of
Directors and/or the Chairman of the Board,  what corporate  functions should be
transferred to and/or handled out of the Reston corporate office.

         6. Expenses.  During Executive's  employment,  Employer shall reimburse
Executive for reasonable,  ordinary and necessary  business expenses incurred by
Executive in the performance of his duties for Employer subject to any budgetary
limitations  established  from time to time by Employer and  provided  Executive
provides  such  documentation  and  information  as  may  then  be  required  by
Employer's  business  expense  reimbursement  policy and as may be  required  to

                                      -7-
<PAGE>

satisfy the standards  necessary to deduct such expenses for federal  income tax
purposes.

         7.       Confidential Information.

                  (a) Executive  acknowledges  Employer is a developing company,
and that, in the course of developing its business,  Employer has developed (and
will develop  and/or  acquire) and Executive will learn,  valuable  Confidential
Information (defined below), which was unknown to Executive prior to Executive's
employment,  or which has been  developed  by  Executive  on behalf of Employer;
which  Confidential  Information  only was and will be disclosed to Executive in
and  under  a  relationship  of  trust  and  confidence  under  restrictions  of
confidentiality.  As used in this Agreement,  Confidential Information means (i)
names,  addresses,  phone  numbers,  dates  and any and  all  other  information
regarding  the  clients or  potential  clients,  customers  and key  contacts at
customers of Employer;  and (ii) trade  secrets,  business,  sales and financial
data, pricing, costs, financial statements,  programs, property, lists, diagrams
and drawings,  information concerning the design,  components and manufacture of
Employer's products, market information, financial and marketing plans, manuals,
strategies, and projections of Employer.  Executive agrees that the Confidential
Information  is a trade secret for  purposes of all  applicable  laws,  and that
Confidential Information would not be disclosed to Executive but for Executive's
execution of this Agreement.

                  (b) Except as required by the duties of Executive's employment
with  Employer,  Executive  shall never during his employment or for a period of
three (3) years after such employment terminates,  directly or indirectly,  use,
publish, or otherwise disclose any Confidential Information,  without Employer's
prior written consent.  This restriction shall not apply to information which is
known  in the  industry  generally  other  than  by  reason  of any  actions  of
Executive.

                  (c) During  Executive's  employment  with Employer,  Executive
shall exercise all due and diligent  precautions to protect the integrity of the
Confidential  Information,  and upon  termination  of  employment,  or otherwise
before then upon  request,  Executive  shall return to Employer all documents or
materials embodying such Confidential Information or any part thereof (including
any copies thereof) in Executive's possession or control.

         8.       Restrictive Covenants.

                  (a)  Executive  acknowledges  and agrees  that  Employer  will
suffer great loss and damage if,  during  Executive's  employment or at any time
subsequent to such  employment,  Executive  were to  improperly  use or disclose
Confidential  Information  or goodwill of Employer,  or if Executive were to use
Executive's  contracts  and  relationships  with any client,  potential  client,
customer,  or referral source of Employer,  and therefore  agrees that Executive
must comply

                                      -8-
<PAGE>


with the restrictive covenants hereinafter set forth; it being understood at the
execution  of this  Agreement  that  the  parties  acknowledge  and  agree  such
restrictions protect legitimate protectable interests of Employer,  with respect
to its trade  secrets,  customers,  and referral  sources,  are  reasonable  and
necessary  to protect  such  interests,  are  comparable  with their  respective
rights, and do not impair or prevent Executive from earning a living.

                  (b) During  Executive's  employment  with Employer and for the
continuous period of one (1) year after such employment  terminates (whether the
Term or any extension  thereof  expires,  the employment  term is non-renewed by
either  party,  or  employment  is  terminated  by  Executive  or  Employer  and
regardless  of the reason for  termination),  Executive  shall not  directly  or
indirectly,  for any reason or purpose  whatsoever (other than on Employer's own
behalf in performing  Executive's  required  duties for  Employer),  whether for
Executive's  own benefit,  or for the benefit or on behalf of, or in conjunction
with,  any other  corporation,  partnership,  proprietorship,  or other  form of
business  entity,  and whether as an  employee  (in any  executive,  managerial,
officer,  exempt or sales  position),  partner,  principal,  officer,  director,
consultant, agent, stockholder or otherwise:

                  (i)      contact,  call on,  solicit the business of, sell any
                           goods or services of a type then provided by Employer
                           to, or attempt to take away from Employer, any client
                           or customer of the  Employer or any  business of such
                           customer of a type then  provided by Employer to such
                           customer;

                  (ii)     engage in any  manner  (or own any  interest)  in any
                           part  of a  business  then  engaged  in by  Employer,
                           anywhere   within  any   metropolitan   area  of  the
                           continental  United States or any other country where
                           Employer then is marketing  and/or  selling its goods
                           or  services  (the  mere  ownership  of less than two
                           percent  (2%) of the  shares of any  publicly  traded
                           corporation  shall not be  considered  a violation of
                           this provision); or

                  (iii)    solicit or encourage any director,  officer, or other
                           employee of Employer to discontinue that individual's
                           status  or   employment   with   Employer,   or  such
                           individual to engage or  participate  in any activity
                           or employment in competition with Employer.

                  (c) It is the intention of the parties to restrict Executive's
activities  only to the  extent  necessary  for  the  protection  of  Employer's
legitimate business interests. To the extent that any covenant set forth in this
Section 8, or in Section 7 of this Agreement,  shall be determined to be invalid
or  unenforceable  in any respect or to any extent,  the  covenant  shall not be
rendered  invalid,  but instead shall be  automatically  amended for such lesser
term or to such  lesser  extent,  or in

                                      -9-
<PAGE>

such other degree, as may grant the Employer or other party seeking  enforcement
the maximum protection and restrictions on Executive's  activities  permitted by
applicable law in such circumstances.

         Executive  acknowledges  and agrees that (a) the  separate and distinct
promises in this  Agreement are reasonable and necessary in order to protect the
legitimate business interests described above, (b) any violation would result in
irreparable  injury to Employer,  and (c) the  enforcement of a remedy by way of
injunction or otherwise would not prevent Executive from earning a living.

         9. Non-Waiver of Covenants.  Employer's  failure to exercise any of its
rights to enforce the provisions of this Agreement  shall not be affected by the
existence or non-existence  of any other similar  agreement for any other person
employed by  Employer,  or by  Employer's  failure to exercise any of its rights
under this  agreement  or any other  similar  agreement.  Employer's  failure to
exercise any of its rights in the event  Executive  breaches any promise in this
Agreement shall not be construed as a waiver of such breach or prevent  Employer
from  later  enforcing  strict  compliance  with  any and all  promises  in this
Agreement.

         10.  Assignment,  Entire Agreement,  Amendments.  This Agreement may be
assigned only by Employer,  and is freely assignable by Employer. It constitutes
the entire agreement  between the parties  concerning the subject matter of this
Agreement and supersedes all prior understandings, communications and agreements
concerning  such subject matter.  Neither this Agreement,  nor any of its terms,
can be changed,  added to, waived or supplemented  except in a written  document
signed by Executive and  Employer,  except that Employer may adopt or change any
vacation,  benefit, rules or other policy generally applicable to employees or a
group or class of  employees  in its  discretion  (excluding  any  change in the
incentive stock option plan which violates the terms of this Agreement).

         11.  Notification.  In order to preserve  Employer's  rights under this
Agreement,  Employer is authorized to advise any third party with whom Executive
may become employed or enter into any business or contractual relationship with,
or whom  Executive  may contact for any such  purpose,  of the existence of this
Agreement and its terms, and Employer shall not be liable for doing so.

         Executive  represents and agrees that  Executive has not provided,  and
will not, provide, to Employer (or utilize in connection with the performance of
his duties), any trade secrets of a prior employer.

         12. Governing Law, Assignment,  Miscellaneous.  This Agreement shall be
governed by and construed and interpreted  according to the internal laws of the
State of Missouri without  reference to conflicts of law principles with respect
to the  application,  interpretation  and  enforceability  of the  covenants and
agreements  set  out  in  Sections  7 and 8 of the  Agreement  and  any  related
provisions  which affect

                                      -10-
<PAGE>

their  enforceability,  application or interpretation;  otherwise this Agreement
shall be governed by and  construed  and  interpreted  according to the internal
laws of the  Commonwealth  of Virginia  without  reference  to  conflicts of law
principles.  The  headings of the  sections  are  inserted  for  convenience  of
reference  only  and  shall  not be  considered  to  constitute  a part  of this
Agreement nor to affect the meaning.

         If any one or more provisions  contained in this  Agreement,  or in the
application thereof,  shall be held to be invalid,  illegal, or unenforceable in
any  respect,  the  validity,  legality  and  enforceability  of  the  remaining
provisions  of this  Agreement  shall not in any way be  affected  or  impaired.
Nothing in this  Agreement  shall be deemed to require  Employer or Executive to
take any  action  or  perform  any  obligation  which  would be  contrary  to or
inconsistent with a Court order.

         Employer  represents  and  agrees  that  the  execution,  delivery  and
performance  of  this  Agreement  do not  conflict  with or  violate  Employer's
articles,  by-laws or resolutions,  or any judgment, order or agreement to which
Employer is a party or may be bound,  and that all corporate action necessary to
authorize  the  Employer's  execution  and delivery of this  Agreement  has been
taken.

         In any suit to enforce this Agreement, venue and jurisdiction is proper
in the County of Virginia in which  Reston,  Virginia (or  Employer's  corporate
offices,  if in a  different  county) is located,  and (if federal  jurisdiction
exists) the federal  district  court for the district in which Reston,  Virginia
(or Employer's  corporate offices, if in a different county) is located, and the
parties waive any objection to jurisdiction  and venue in any such forum and any
claim that such forum is not the most convenient forum.

         13.  Acknowledgment;   Indemnification.   By  signing  this  Agreement,
Executive and Employer each  acknowledge  and agree that they each have read the
Agreement,  understand  and intend to fulfill each and every one of the promises
in  this  Agreement,  understand  this  is  a  legally  binding  agreement,  and
acknowledge receiving a copy of the Agreement.

         Employer  will  indemnify,  defend  (at  Employer's  expense)  and hold
harmless  Executive from and against any claim asserted by Digex,  Incorporated,
Digital  Express  Group  or  Intermedia  Communications  or any  successor  that
Executive's employment under this Agreement, or any solicitation of customers or
employees of any such company,  violates any current or prior agreement  between
Executive and any such company  which has been  provided to Employer;  provided,
however,  that Executive  provides  prompt notice to Employer of any such claim,
and cooperates fully in the defense thereof, and provided that Employer controls
the defense and settlement of the claim. This indemnification does not extend to
actions taken by Executive  contrary to any specific  instructions of Employer's
Board or its  Chairman or to any use or  disclosure  by Executive of any legally
protectable trade secrets of

                                      -11-
<PAGE>

another, it being understood that Executive is not authorized to use or disclose
to Employer any such trade secrets in connection with Executive's employment.

         14. Notice.  Every notice,  demand or other  communication  required or
contemplated  by this Agreement shall be in writing and deemed to have been made
either when  personally  delivered to the  respective  party or deposited in the
ordinary U.S. mail,  first-class postage prepaid, to the address set forth below
under such party's  signature,  or to such  changed  address as either party may
have given by written notice to the other party.

         IN WITNESS  WHEREOF,  the parties  hereto  have  signed this  Agreement
below, this 4th day of December, 1998.

EXECUTIVE                                     SAVVIS COMMUNICATIONS
                                              CORPORATION


/s/ C.A. Heintzelman                          By  /s/ John S. McCarthy
-------------------------------                   ------------------------------
                                              Its Chairman of the Board


Residing at 15105 Sunflower Ct.
            Rockville, Md.  20853-1749


                                       12

Source: OneCLE Business Contracts.