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                                                                   EXHIBIT 10.35

                          CONCORD COMMUNICATIONS, INC.

                     MANAGEMENT CHANGE IN CONTROL AGREEMENT

         MANAGEMENT CHANGE IN CONTROL AGREEMENT entered into this 18th day of
November, 2002 by and among Concord Communications, Inc., a Massachusetts
corporation ("Concord"), and the undersigned employee of Concord, Daniel Sheahan
(the "Employee").

                                   WITNESSETH:

         WHEREAS, Concord and the Employee desire to set forth certain terms and
conditions relating to benefits to be afforded to Employee upon the occurrence
of a Change in Control (as hereinafter defined) of Concord;

         NOW THEREFORE, in consideration of the premises and of the mutual
covenants and agreements hereinafter set forth, the parties hereto hereby agree
as follows:

         1.       Severance and Option Acceleration. (a) During the Term (as
hereinafter defined), if within six (6) months of a Change in Control of
Concord, Concord (or any successor corporation) terminates (each, a "Termination
Event") the Employee's employment without Cause (as hereinafter defined) or the
Employee voluntarily terminates his/her employment for Good Reason (as
hereinafter defined), the Employee shall receive a single severance payment in
cash in an amount equal to six months' base annual salary (at the rate being
paid to him/her immediately prior to such termination) (the "Severance
Benefit"). The Employee shall not be entitled to continue to receive (i) any
other salary or bonus in the event of a termination for any reason or (ii) any
other employee benefits (other than those specified in the following sentence)
in the event of a termination for any reason. Notwithstanding the foregoing,
Concord shall continue to pay Concord's share of the Employee's health insurance
in accordance with Concord's general policies for a period of six months
following any Termination Event.

         (b)      "Good Reason" means the occurrence of one or more of the
following events during the Term and following a Change in Control:

                  (i)      Without the Employee's express written consent,
         Concord shall reduce the Employee's duties and responsibilities from
         those assigned to the Employee immediately prior to the Change in
         Control; or

                  (ii)     Without the Employee's express written consent,
         Concord shall require the Employee to have his/her principal location
         of work changed to any location which is in excess of 60 miles from the
         location thereof immediately prior to the Change in Control; or

                  (iii)    Without the Employee's express written consent,
         Concord shall materially reduce the Employee's benefits under existing
         benefit plans, unless there is a concurrent reduction uniformly among
         all persons entitled to such benefits.

         (c)      Effective upon the date immediately following any Change in
Control of Concord, the "Full Vest" date(s) set forth in each of the Employee's
then outstanding Notice of Option Grant shall be automatically accelerated by
twenty-four (24) months. Notwithstanding the foregoing, if within twenty-four
(24) months after a Change in Control there is a Termination Event, all of the
Employee's unvested options (but only such options as have been granted to the
Employee by Concord as of the date of the Change in Control or such options as
have been exchanged by the Employee for new options in any acquiring company at
the time of a Change in Control) shall automatically become fully vested as of
the date of such Termination Event.

         (d)      For purposes of this Agreement, a "Change in Control" shall
have occurred if at any time any of the following events shall occur:

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                  (A) Concord is merged, consolidated or reorganized into or
                  with another corporation or other legal person, and as a
                  result of such merger, consolidation or reorganization less
                  than a majority of the combined voting power of the
                  then-outstanding securities of the combined corporation or
                  person immediately after such transaction are held in the
                  aggregate by the holders of the combined voting power of the
                  then-outstanding securities entitled to vote generally in the
                  election of directors of Concord ("Voting Stock") immediately
                  prior to such transaction;

                  (B) Concord sells or otherwise transfers all or substantially
                  all of its assets to any other corporation or other legal
                  person, and less than a majority of the combined voting power
                  of the then-outstanding securities of such corporation or
                  person immediately after such sale or transfer is held in the
                  aggregate by the holders of the Voting Stock of Concord
                  immediately prior to such sale or transfer;

                  (C) There is a report filed on Schedule 13D or Schedule 14D-1
                  (or any successor schedule, form or report), each as
                  promulgated pursuant to the Exchange Act of 1934 (the "1934
                  Act"), disclosing that any person (as the term "person" is
                  used in Section 13(d)(3) or Section 14(d)(2) of the 1934 Act)
                  has become the beneficial owner (as the term "beneficial
                  owner" is defined under Rule 13d-3 or any successor rule or
                  regulation promulgated under the 1934 Act) of securities
                  representing 33% or more of the Voting Stock; or

                  (D) Concord files a report or proxy statement with the
                  Securities and Exchange Commission pursuant to the 1934 Act
                  disclosing in response to Form 8-K or Schedule 14A (or any
                  successor schedule, form or report or item therein) that a
                  change in control of Concord has or may have occurred or will
                  or may occur in the future pursuant to any then-existing
                  contract or transaction.

provided, however, that notwithstanding the foregoing provisions of this Section
1, a "Change in Control" shall not be deemed to have occurred for purposes of
this Agreement solely because (i) Concord, (ii) an entity in which Concord
directly or indirectly beneficially owns 50% or more of the voting securities,
(iii) any Concord sponsored employee stock ownership plan or any other employee
benefit plan of Concord, or (iv) any corporation or legal person approved by the
Board of Directors prior to the occurrence of the event that, absent such
approval by the Board of Directors, would have constituted a Change in Control,
either files or becomes obligated to file a report or a proxy statement under or
in response to Schedule 13D, Schedule 14D-1, Form 8-K or Schedule 14A (or any
successor schedule, form or report or item therein) under the 1934 Act,
disclosing beneficial ownership by it of shares of Voting Stock, whether in
excess of 33% or otherwise, or because Concord reports that a change in control
of Concord has or may have occurred or will or may occur in the future by reason
of such beneficial ownership.

         (e)      Notwithstanding anything to the contrary in this Agreement, if
the Employee is a Disqualified Individual (as defined in Section 280G of the
Internal Revenue Code of 1986, as amended (the "Code")) and if any portion of
any acceleration of vesting, payment or transfer of property under this
Agreement would be an Excess Parachute Payment (as defined in Section 280G of
the Code) but for the application of this sentence, then the amount of such
acceleration, payment or transfer otherwise payable to the Employee pursuant to
this Agreement shall be reduced to the minimum extent necessary (but in no event
to less than zero) so that no portion of such payment, as so reduced,
constitutes an Excess Parachute Payment; provided, however, that no reduction
shall be made if the net economic effect would be disadvantageous to the
Employee, taking into account all the facts and circumstances including any tax
savings resulting from the reduction.

         2.       Termination. (a) Concord may, immediately and unilaterally,
terminate the Employee's employment hereunder for "Cause" at any time. As used
in this Agreement, the term "Cause" shall mean:

                  (i)      the Employee's willful and substantial misconduct
                  with respect to the business and affairs of Concord, or any
                  subsidiary or affiliate thereof;

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                  (ii)     the Employee's gross neglect of duties, dishonesty,
                  deliberate disregard of any material rule or policy of Concord
                  or the commission by the Employee of any other action with the
                  intent to injure Concord, or any subsidiary or affiliate
                  thereof;

                  (iii)    the Employee's commission of an act involving
                  embezzlement or fraud or commission of a felony; or

                  (iv)     the commission of an act which induces any customer
                  of Concord to breach a contract or purchase order with
                  Concord, or any subsidiary or affiliate thereof.

         In the event of a termination for "Cause" as described herein, the
Employee shall not be entitled to severance or other termination benefits,
including, without limitation, the benefits described in Section 1 herein.

         (b)      The Employee's employment shall automatically terminate upon
his/her death and may be terminated by Concord due to him/her disability. If the
Employee dies or his/her employment is terminated due to disability during the
Term, then Employee shall be eligible for such benefits as shall apply to
employees of Concord generally under such circumstances at the time of such
termination.

         As used in this Agreement, the term "disability" shall mean the
occurrence of a mental or physical condition which renders the Employee
incapable of performing his/her duties for a total of six consecutive months.

         (c)      The Employee understands that, prior to any Change in Control,
Concord may terminate the Employee with or without "Cause" at any time.
Following any Change in Control, Concord may also terminate the Employee with or
without "Cause" at any time subject to the Employee's rights and Concord's
obligations specified in this Agreement.

         3.       No Obligation of Employment. Employee understands that the
employment relationship between Employee and Concord will be "at will" and that
Concord may terminate such relationship with or without Cause or for any reason
or no reason.

         4.       Noncompetition Agreement. Employee shall execute concurrently
herewith the form of Noncompetition Agreement attached hereto as Exhibit A.

         5.       Consent and Waiver by Third Parties. The Employee hereby
represents and warrants that he/she has obtained all waivers and/or consents
from third parties which are necessary to enable him/her to execute and perform
this Agreement without being in conflict with any other agreement, obligation or
understanding with any such third party.

         6.       Governing Law. This Agreement shall be governed by and
construed in accordance with the internal laws of the Commonwealth of
Massachusetts and this Agreement shall be deemed to be performable in
Massachusetts.

         7.       Severability. In case any one or more of the provisions
contained in this Agreement for any reason shall be held to be invalid, illegal
or unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other provision of this Agreement and this Agreement shall
be construed to the maximum extent permitted by law.

         8.       Waivers and Modifications. This Agreement may be modified, and
the rights, remedies and obligations contained in any provision hereof may be
waived, only in accordance with this Section 8. No waiver by either party of any
breach by the other or any provision hereof shall be deemed to be a waiver of
any later or other breach thereof or as a waiver of any other provision of this
Agreement. This Agreement sets forth all of the terms of the understandings
between the parties with reference to the subject matter set forth herein and
may not be waived, changed, discharged or terminated orally or by any course of
dealing between the parties, but only by an instrument in writing signed by the
party against whom any waiver, change, discharge or termination is sought.

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         9.       Assignment. The Employee may not assign any of his/her rights
or delegate any of his/her duties or obligations under this Agreement. The
rights and obligations of Concord under this Agreement shall inure to the
benefit of, and shall be binding upon, the successors and assigns of Concord.

         10.      Entire Agreement. This Agreement constitutes the entire
understanding of the parties relating to the subject matter hereof and
supersedes and cancels all agreements, written or oral, made prior to the date
hereof between the Employee and Concord relating to the subject matter hereof;
provided, however, that the Employee's existing option agreements, as modified
hereby, shall remain in effect.

         11.      Notices. All notices hereunder shall be in writing and shall
be delivered in person or mailed by certified or registered mail, return receipt
requested, addressed as follows:

         If to Concord, to:  Concord Communications, Inc.
                                    600 Nickerson Road
                                    Marlboro, MA 01752
                                    Attention: John A. Blaeser

                                    With a copy to:
                                    Concord Communications, Inc.
                                    600 Nickerson Road
                                    Marlboro, MA 01752
                                    Attention: General Counsel

         If to the Employee, at the Employee's address set forth on the
signature page hereto.

         12.      Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed to be an original, but all of which
together shall constitute one and the same instrument.

         13.      Section Headings. The descriptive section headings herein have
been inserted for convenience only and shall not be deemed to define, limit, or
otherwise affect the construction of any provision hereof.

         14.      Term. The term of this Agreement (the "Term") shall commence
upon the date hereof and terminate upon the earlier of (i) twenty-four (24)
months following any Change in Control of Concord, (ii) the date prior to any
Change in Control of Concord that the Employee for any reason ceases to be an
employee of Concord and (iii) the date following any Change in Control of
Concord that the Employee is terminated for Cause or voluntary terminates his
employment (other than for Good Reason).

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the day and
year first above written.

                               CONCORD COMMUNICATIONS, INC.

                               By:/s/John A. Blaeser
                                  ----------------------------------------------
                                  Name: John A. Blaeser
                                  Title: President and Chief
                                  Executive Officer

                                  EMPLOYEE

                                  /s/Daniel Sheahan
                                  ----------------------------------------------
                                  Name: Daniel Sheahan
                                  Address:

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                        EMPLOYEE NONCOMPETITION AGREEMENT

         In consideration and as a condition of my continued employment, I
hereby agree with Concord Communications, Inc. ("Concord") as follows:

         1.       During the period of my employment by Concord (the "Employment
Period"), I will devote my full working time and best efforts to the business of
Concord. Further, (i) for as long as I am an employee of Concord and (ii) for
the period beginning as of the date of the occurrence of a Change in Control
through and including the date to occur which is six months following the date
upon which I am no longer an employee of Concord, I agree that I will not,
directly or indirectly, alone or as a partner, officer, director, employee or
stockholder of any entity (except that I may own not more than 1% of the
outstanding shares of any publicly-traded company), engage in any business
activity which is in competition with the products or services being developed,
manufactured or sold by Concord. The provisions of clause (ii) of the preceding
sentence shall (A) apply only if following a Change in Control my employment
with Concord shall have been terminated (1) without cause or for cause pursuant
to Section 2 of my Management Change in Control Agreement of even date herewith
or (2) for "Good Reason" (as that term is defined in my Management Change in
Control Agreement) and (B) not apply if I shall have voluntarily terminated my
employment with Concord. The period following the termination of my employment
during which the restrictions described above shall apply (the "Post-employment
Period") shall be extended by the length of any period of time during the
Post-employment Period during which I am in violation of this paragraph. Nothing
contained herein shall exclude me from participating in civic, charitable,
religious or non-profit activities so long as such activities do not interfere
with the performance of my duties to Concord.

         2.       I agree that any breach of this Agreement by me will cause
irreparable damage to Concord and that in the event of such breach Concord shall
have, in addition to any and all remedies of law, the right to an injunction,
specific performance or other equitable relief to prevent the violation of my
obligations hereunder. I further agree and acknowledge that the post-employment
non-competition provision set forth in Paragraph 1 hereof, and the remedies set
forth in this paragraph, are necessary and reasonable to protect the business of
Concord.

         3.       I understand that this Agreement does not create an obligation
on Concord or any other person or entity to continue my employment.

         4.       No claim of mine against Concord shall serve as a defense
against Concord's enforcement of any provision of this Agreement.

         5.       I hereby represent that I am not a party to, or bound by the
terms of, any agreement with any previous employer, other than Concord, or other
party to refrain from using or disclosing any trade secret or confidential or
proprietary information in the course of my employment with Concord or to
refrain from competing, directly or indirectly, with the business of such
previous employer or any other party, which would prevent me from performing
services to or for Concord in any material way. I further represent that my
performance of all the terms of this Agreement and as an employee of Concord
does not and will not breach any agreement to keep in confidence proprietary
information, knowledge or data acquired by me in confidence or in trust prior to
my employment with Concord, and I will not disclose to Concord or induce Concord
to use any confidential or proprietary information or material belonging to any
previous employer or others. I have not entered into, and I agree I will not
enter into, any agreement, either written or oral, in conflict with the terms of
this Agreement.

         6.       Any waiver by Concord of a breach of any provision of this
Agreement shall not operate or be construed as a waiver of any subsequent breach
of such provision or any other provision hereof.

         7.       I hereby agree that each provision herein shall be treated as
a separate and independent clause, and the unenforceability of any one clause
shall in no way impair the enforceability of any of the other clauses herein.
Moreover, if one or more of the provisions contained in this Agreement shall for
any reason be held to be excessively broad as to scope, activity, subject or
otherwise so as to be unenforceable at law, such provision or provisions shall
be construed by the appropriate judicial body by limiting or reducing it or
them, so as to be enforceable to the maximum extent compatible with the
applicable law as it shall then appear.

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         8.       My obligations under this Agreement shall survive the
termination of my employment regardless of the manner of such termination.

         9.       The term "Concord" as used herein shall also include Concord's
subsidiaries, subdivisions or affiliates. Concord shall have the right to assign
this Agreement to its successors and assigns, and all covenants and agreements
hereunder shall inure to the benefit of and be enforceable by said successors or
assigns.

         10.      This Agreement shall be governed by and construed in
accordance with the internal laws of the Commonwealth of Massachusetts. Any
claims or legal actions by one party against the other arising out of the
relationship between the parties contemplated herein (whether or not arising
under this Agreement) shall be governed by the laws of the Commonwealth of
Massachusetts and shall be commenced and maintained in any state or federal
court located in Massachusetts, and both parties hereby submit to the
jurisdiction and venue of any such court.

         11.      Capitalized terms used herein and not otherwise defined shall
have the meanings provided in the Management Change in Control Agreement of even
date herewith.

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IN WITNESS WHEREOF, the undersigned has executed this Agreement as of the 18th
day of November, 2002.

                                  /s/Daniel Sheahan
                                  ----------------------------------------------
                                  Name: Daniel Sheahan

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