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                                                                   EXHIBIT 10.08

                          CONCORD COMMUNICATIONS, INC.

                  1997 NON-EMPLOYEE DIRECTOR STOCK OPTION PLAN
  (AS AMENDED MARCH 12, 1998, MARCH 8, 2000, APRIL 25, 2001, FEBRUARY 6, 2002,
                                AUGUST 20, 2004)

      1. Purpose. This Non-Qualified Stock Option Plan, to be known as the 1997
Non-Employee Director Stock Option Plan (hereinafter, this "Plan") is intended
to promote the interests of CONCORD COMMUNICATIONS, INC. (hereinafter, the
"Company") by providing an inducement to obtain and retain the services of
qualified persons who are not employees or officers of the Company to serve as
members of its Board of Directors (the "Board").

      2. Available Shares. The total number of shares of Common Stock, par value
$.01 per share, of the Company (the "Common Stock") for which options may be
granted under this Plan shall not exceed three hundred thirty thousand (330,000)
shares, subject to adjustment in accordance with Section 10 of this Plan;
provided, however, that such number of shares shall not be subject to adjustment
by reason of the stock split in the form of a stock dividend declared by the
Board of the Directors of the Company on August 7, 1997. Shares subject to this
Plan are authorized but unissued shares or shares that were once issued and
subsequently reacquired by the Company. If any options granted under this Plan
are surrendered before exercise or lapse without exercise, in whole or in part,
the shares reserved therefor shall continue to be available under this Plan.

      3. Administration. This Plan shall be administered by the Board or by a
committee appointed by the Board (the "Committee"). In the event the Board fails
to appoint or refrains from appointing a Committee, the Board shall have all
power and authority to administer this Plan. In such event, the word "Committee"
wherever used herein shall be deemed to mean the Board. The Committee shall,
subject to the provisions of the Plan, have the power to construe this Plan, to
determine all questions hereunder, and to adopt and amend such rules and
regulations for the administration of this Plan as it may deem desirable. No
member of the Board or the Committee shall be liable for any action or
determination made in good faith with respect to this Plan or any option granted
under it.

      4. Automatic Grant of Options. Subject to the availability of shares under
this Plan, (a) each person who becomes a member of the Board on or after October
16, 1997 and who is not an employee or officer of the Company during the term of
the Plan (a "Non-Employee Director"), shall be granted on the date such person
is first elected to the Board, without further action by the Board, an option to
purchase 25,000 shares of Common Stock, and (b) each person who is a
Non-Employee Director immediately following the final adjournment of each Annual
Meeting of Stockholders of the Company during the term of this Plan shall be
automatically granted on each such date an option to purchase 10,000 shares of
Common Stock. The options to be granted under this Section 4 shall be the only
options ever to be granted at any time to such member under this Plan. The
number of shares covered by options granted under this Section 4 shall be
subject to adjustment in accordance with the provisions of Section 10 of this
Plan.

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      5. Option Price. The purchase price of the stock covered by an option
granted pursuant to this Plan shall be 100% of the fair market value of such
shares on the day the option is granted. The option price will be subject to
adjustment in accordance with the provisions of Section 10 of this Plan. For
purposes of this Plan, if, at the time an option is granted under the Plan, the
Company's Common Stock is publicly traded, "fair market value" shall be
determined as of the last business day for which the prices or quotes discussed
in this sentence are available prior to the date such option is granted and
shall mean (i) the average (on that date) of the high and low prices of the
Common Stock on the principal national securities exchange on which the Common
Stock is traded, if the Common Stock is then traded on a national securities
exchange; or (ii) the last reported sale price (on that date) of the Common
Stock on the Nasdaq National Market, if the Common Stock is not then traded on a
national securities exchange; or (iii) the closing bid price (or average of bid
prices) last quoted (on that date) by an established quotation service for
over-the-counter securities, if the Common Stock is not reported on the Nasdaq
National Market List. However, if the Common Stock is not publicly traded at the
time an option is granted under the Plan, "fair market value" shall be deemed to
be the fair value of the Common Stock as determined by the Committee after
taking into consideration all factors which it deems appropriate, including,
without limitation, recent sale and offer prices of the Common Stock in private
transactions negotiated at arm's length.

      6. Period of Option. Unless sooner terminated in accordance with the
provisions of Section 8 of this Plan, an option granted hereunder shall expire
on the date which is ten (10) years after the date of grant of the option.

      7.    (a) Vesting of Shares and Non-Transferability of Options. Options
granted under this Plan shall not be exercisable until they become vested.
Options granted under this Plan shall vest in the optionee and thus become
exercisable, in accordance with the following schedule, provided that the
optionee has continuously served as a member of the Board through such vesting
date:

            Percentage of Option
            Shares for which
            Option Will be Exercisable  Date of Vesting

                      25%               one year from the date of grant

                      6.25%             per quarter on the last day of the
                                        quarter beginning the quarter ending
                                        immediately following the date to occur
                                        which is one year from the date of grant

      The number of shares as to which options may be exercised shall be
cumulative, so that once the option shall become exercisable as to any shares it
shall continue to be exercisable as to said shares, until expiration or
termination of the option as provided in this Plan.


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            (b) Non-transferability. Any option granted pursuant to this Plan
shall not be assignable or transferable other than by will or the laws of
descent and distribution or pursuant to a domestic relations order and shall be
exercisable during the optionee's lifetime only by him or her.

      8. Termination of Option Rights.

            (a) In the event an optionee ceases to be a member of the Board for
any reason other than death or permanent disability, any then unexercised
portion of options granted to such optionee shall, to the extent not then
vested, immediately terminate and become void; any portion of an option which is
then vested but has not been exercised at the time the optionee so ceases to be
a member of the Board may be exercised, to the extent it is then vested, by the
optionee within 60 days of the date the optionee ceased to be a member of the
Board; and all options shall terminate after such 60 days have expired.

            (b) In the event that an optionee ceases to be a member of the Board
by reason of his or her death or permanent disability, any option granted to
such optionee may be exercised, to the extent of the number of shares with
respect to which he or she could have exercised it on the date of death or
permanent disability, by the optionee (or by the optionee's personal
representative, heir or legatee, in the event of death) until the scheduled
expiration date of the option.

      9. Exercise of Options and Resale Restrictions.

            (a) Exercise of Option. Subject to the terms and conditions of this
Plan and the option agreements, an option granted hereunder shall, to the extent
then exercisable, be exercisable in whole or in part by giving written notice to
the Company by mail or in person addressed to the Chief Financial Officer at 600
Nickerson Road, Marlboro, Massachusetts 01752, its principal executive offices,
stating the number of shares with respect to which the option is being
exercised, accompanied by payment in full for such shares. Payment may be (a) in
United States dollars in cash or by check, (b) in whole or in part in shares of
the Common Stock of the Company already owned by the person or persons
exercising the option or shares subject to the option being exercised (subject
to such restrictions and guidelines as the Board may adopt from time to time),
valued at fair market value determined in accordance with the provisions of
Section 5 or (c) consistent with applicable law, through the delivery of an
assignment to the Company of a sufficient amount of the proceeds from the sale
of the Common Stock acquired upon exercise of the option and an authorization to
the broker or selling agent to pay that amount to the Company, which sale shall
be at the participant's direction at the time of exercise; provided, however,
that there shall be no such exercise at any one time as to fewer than one
hundred (100) shares or all of the remaining shares then purchasable by the
person or persons exercising the option, if fewer than one hundred (100) shares.
The Company's transfer agent shall, on behalf of the Company, prepare a
certificate or certificates representing such shares acquired pursuant to
exercise of the option, shall register the optionee as the owner of such shares
on the books of the Company and shall cause the fully executed certificate(s)
representing such shares to be delivered to the optionee as soon as practicable
after payment of the option price in


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full. The holder of an option shall not have any rights of a stockholder with
respect to the shares covered by the option, except to the extent that one or
more certificates for such shares shall be delivered to him or her upon the due
exercise of the option.

            (b) Resale Restrictions. Under no circumstances may shares acquired
pursuant to the exercise of options granted pursuant to this Plan be disposed of
on or prior to the date that is six months after the date such options were
granted.

      10. Adjustments Upon Changes in Capitalization and Other Events. Upon the
occurrence of any of the following events, an optionee's rights with respect to
options granted to him or her hereunder shall be adjusted as hereinafter
provided:

            (a) Stock Dividends and Stock Splits. If the shares of Common Stock
shall be subdivided or combined into a greater or smaller number of shares or if
the Company shall issue any shares of Common Stock as a stock dividend on its
outstanding Common Stock, the number of shares of Common Stock deliverable upon
the exercise of options shall be appropriately increased or decreased
proportionately, and appropriate adjustments shall be made in the purchase price
per share to reflect such subdivision, combination or stock dividend.

            (b) Recapitalization Adjustments. In the event of a reorganization,
recapitalization, merger, consolidation, or any other change in the corporate
structure or shares of the Company, to the extent permitted by Rule 16b-3 under
the Securities Exchange Act of 1934, adjustments in the number and kind of
shares authorized by this Plan and in the number and kind of shares covered by,
and in the option price of outstanding options under this Plan necessary to
maintain the proportionate interest of the optionee and preserve, without
exceeding, the value of such option, shall be made. Notwithstanding the
foregoing, no such adjustment shall be made which would, within the meaning of
any applicable provisions of the Internal Revenue Code of 1986, as amended,
constitute a modification, extension or renewal of any Option or a grant of
additional benefits to the holder of an Option.

            (c) Issuances of Securities. Except as expressly provided herein, no
issuance by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall affect, and no adjustment
by reason thereof shall be made with respect to, the number or price of shares
subject to options. No adjustments shall be made for dividends paid in cash or
in property other than securities of the Company.

            (d) Adjustments. Upon the happening of any of the foregoing events,
the class and aggregate number of shares set forth in Sections 2 and 4 of this
Plan that are subject to options which previously have been or subsequently may
be granted under this Plan shall also be appropriately adjusted to reflect such
events. The Board shall determine the specific adjustments to be made under this
Section 10 and its determination shall be conclusive.

            (e) Consolidations or Mergers. If the Company is to be consolidated
with or acquired by another entity in a merger or other reorganization in which
the holders of the outstanding voting stock of the Company immediately preceding
the consummation of such


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event, shall, immediately following such event, hold, as a group, less than a
majority of the voting securities of the surviving or successor entity, or in
the event of a sale of all or substantially all of the Company's assets or
otherwise (each, an "Acquisition"), the vesting of all outstanding options
issued pursuant hereto will be accelerated so that all outstanding options are
vested and exercisable in full prior to the consummation of any such
Acquisition. If such options are not exercised prior to the consummation of such
Acquisition, and are not assumed or replaced by the successor entity, such
options will terminate.

      11. Restrictions on Issuance of Shares. Notwithstanding the provisions of
Sections 4 and 9 of this Plan, the Company shall have no obligation to deliver
any certificate or certificates upon exercise of an option until one of the
following conditions shall be satisfied:

            (i) The issuance of shares with respect to which the option has been
exercised is at the time of the issue of such shares effectively registered
under applicable Federal and state securities laws as now in force or hereafter
amended; or

            (ii) Counsel for the Company shall have given an opinion that the
issuance of such shares is exempt from registration under Federal and state
securities laws as now in force or hereafter amended; and the Company has
complied with all applicable laws and regulations with respect thereto,
including without limitation all regulations required by any stock exchange upon
which the Company's outstanding Common Stock is then listed.

      12. Legend on Certificates. The certificates representing shares issued
pursuant to the exercise of an option granted hereunder shall carry such
appropriate legend, and such written instructions shall be given to the
Company's transfer agent, as may be deemed necessary or advisable by counsel to
the Company in order to comply with the requirements of the Securities Act of
1933 or any state securities laws.

      13. Representation of Optionee. If requested by the Company, the optionee
shall deliver to the Company written representations and warranties upon
exercise of the option that are necessary to show compliance with Federal and
state securities laws, including representations and warranties to the effect
that a purchase of shares under the option is made for investment and not with a
view to their distribution (as that term is used in the Securities Act of 1933).

      14. Option Agreement. Each option granted under the provisions of this
Plan shall be evidenced by an option agreement, which agreement shall be duly
executed and delivered on behalf of the Company and by the optionee to whom such
option is granted. The option agreement shall contain such terms, provisions and
conditions not inconsistent with this Plan as may be determined by the officer
executing it.

      15. Termination and Amendment of Plan. Options may no longer be granted
under this Plan ten (10) years after the Approval Date, and this Plan shall
terminate when all options granted or to be granted hereunder are no longer
outstanding. The Board may at any time terminate this Plan or make such
modification or amendment thereof as it deems advisable;


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provided, however, that the Board may not, without approval of the stockholders,
modify or amend this Plan, if such approval is required by the Federal
securities laws or applicable regulatory authorities (at the time of any such
modification or amendment). Termination or any modification or amendment of this
Plan shall not, without consent of a participant, affect his or her rights under
an option previously granted to him or her. The Plan was adopted by the Board of
Directors in July 1997 and by the stockholders of the Company on September 9,
1997. The Plan was amended on March 12, 1998 by the Board of Directors to
increase the number of option shares granted to Directors on the date such
person is first elected to the Board from 7,500 shares to 20,000 shares and to
increase the number of option shares automatically granted to Directors
immediately following the final adjournment of each Annual Meeting of
Stockholders from 1,875 shares to 5,000 shares. The Plan was further amended on
March 8, 2000 by the Board of Directors to increase the number of shares
authorized for issuance under the Plan by 35,000 subject to approval of the
amendment of the Plan by the stockholders of the Company at the next meeting of
stockholders. The stockholders of the Company approved such amendment on April
25, 2000. The Plan was further amended on April 25, 2001 to increase the number
of option shares automatically granted to Directors immediately following the
final adjournment of each Annual Meeting of Stockholders from 5,000 shares to
7,500 shares. The Plan was further amended on February 6, 2002 by the Board of
Directors to increase the number of shares authorized for issuance under the
Plan by 200,000 subject to approval of the amendment of the Plan by the
stockholders of the Company at the next meeting of stockholders. The
stockholders of the Company approved such amendment on April 24, 2002. The Plan
was further amended by the Board of Directors on August 20, 2004 to increase the
number of option shares automatically granted to Directors on the date such
person is first elected to the Board from 20,000 shares to 25,000 shares and to
increase the number of option shares automatically granted to Directors
immediately following the final adjournment of each Annual Meeting of
Stockholders from 7,500 to 10,000 shares.

      16. Withholding of Income Taxes. Upon the exercise of an option, the
Company, in accordance with Section 3402(a) of the Internal Revenue Code, may
require the optionee to pay withholding taxes in respect of amounts considered
to be compensation includible in the optionee's gross income.

      17. Compliance with Regulations. It is the Company's intent that the Plan
comply in all respects with Rule 16b-3 under the Securities Exchange Act of 1934
(or any successor or amended provision thereof) and any applicable Securities
and Exchange Commission interpretations thereof. If any provision of this Plan
is deemed not to be in compliance with Rule 16b-3, the provision shall be null
and void.

      18. Governing Law. The validity and construction of this Plan and the
instruments evidencing options shall be governed by the laws of the Commonwealth
of Massachusetts, without giving effect to the principles of conflicts of law
thereof.