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                                                                    EXHIBIT 10.3

                               CIDRA CORPORATION

                       2000 EMPLOYEE STOCK PURCHASE PLAN

         The following constitute the provisions of the 2000 Employee Stock
Purchase Plan (the "Plan") of CiDRA Corporation (the "Company").

         1. Purpose. The purpose of the Plan is to provide Employees of the
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Company and its Designated Subsidiaries with an opportunity to purchase Common
Stock of the Company. It is the intention of the Company to have the Plan
qualify as an "Employee Stock Purchase Plan" under Section 423 of the Internal
Revenue Code of 1986, as amended. The provisions of the Plan shall, accordingly,
be construed so as to extend and limit participation in a manner consistent with
the requirements of that section of the Code.

         2.  Definitions.
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         (a) "Board" shall mean the Board of Directors of the Company, or a
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committee of the Board of Directors named by the Board to administer the Plan.

         (b) "Code" shall mean the Internal Revenue Code of 1986, as amended.
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         (c) "Common Stock" shall mean the Common Stock, $.001 par value, of
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             the Company.

         (d) "Company" shall mean CiDRA Corporation, a Delaware corporation.
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         (e) "Compensation" shall mean all compensation that is taxable income
              ------------
for federal income tax purposes, including, payments for overtime, shift
premium, incentive compensation, incentive payments, bonuses, commissions and
other compensation received from the Company or a Designated Subsidiary, but
excludes relocation, expense reimbursements, tuition or other reimbursements and
income realized as a result of participation in any stock option, stock purchase
or similar plan of the Company or a Designated Subsidiary.

         (f) "Continuous Status as an Employee" shall mean the absence of any
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interruption or termination of service as an Employee. Continuous Status as an
Employee shall not be considered interrupted in the case of a leave of absence
agreed to in writing by the Company, provided that such leave is for a period of
not more than 90 days or reemployment upon the expiration of such leave is
guaranteed by contract or statute.

         (g) "Contributions" shall mean all amounts credited to the account of a
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participant pursuant to the Plan.

         (h) "Designated Subsidiaries" shall mean the Subsidiaries which have
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been designated by the Board from time to time in its sole discretion as
eligible to participate in the Plan.

         (i) "Employee" shall mean any person, including an officer, who is
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customarily employed for at least 20 hours per week and more than five months in
a calendar year by the Company or one of its Designated Subsidiaries.

         (j) "Exercise Date" shall mean the last day of each Offering Period of
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the Plan.

         (k) "Offering Date" shall mean the first business day of each Offering
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Period of the Plan, except that in the case of an individual who becomes an
eligible Employee after the first business day of an Offering Period but on or
prior to the first business day of the fourth calendar month within such
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Offering Period, the term "Offering Date" shall mean the first business day of
such fourth calendar month coinciding with or next succeeding the day on which
that individual becomes an eligible Employee.

         Options granted after the first business day of an Offering Period will
be subject to the same terms as the options granted on the first business day of
such Offering Period except that they will have a different grant date (thus,
potentially, a different exercise price) and, because they expire at the same
time as the options granted on the first business day of such Offering Period, a
shorter term.

         (l) "Offering Period" shall mean a period of six months commencing on
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April 1 and October 1 of each calendar year, other than the initial offering
period as set forth in Paragraph 4.

         (m) "Plan" shall mean this CiDRA Corporation 2000 Employee Stock
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Purchase Plan.

         (n) "Subsidiary" shall mean a corporation, domestic or foreign, of
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which not less than 50% of the voting shares are held by the Company or a
Subsidiary, whether or not such corporation now exists or is hereafter organized
or acquired by the Company or a Subsidiary.

         3.  Eligibility.
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         (a) Any person who has been continuously employed as an Employee for
three (3) months as of the Offering Date of a given Offering Period shall be
eligible to participate in such Offering Period under the Plan, provided that
such person was not eligible to participate in such Offering Period as of any
prior Offering Date, and further, subject to the requirements of Paragraph 5(a)
and the limitations imposed by Section 423(b) of the Code.

         (b) Any provisions of the Plan to the contrary notwithstanding, no
Employee shall be granted an option under the Plan (i) if, immediately after the
grant, such Employee (or any other person whose stock would be attributed to
such Employee pursuant to Section 424(d) of the Code) would own stock and/or
hold outstanding options to purchase stock possessing five percent (5%) or more
of the total combined voting power or value of all classes of stock of the
Company or of any Subsidiary of the Company, or (ii) which permits his or her
rights to purchase stock under all employee stock purchase plans (described in
Section 423 of the Code) of the Company and its Subsidiaries to accrue at a rate
which exceeds $25,000 of fair market value of such stock (determined at the time
such option is granted) for each calendar year in which such option is
outstanding at any time. Any option granted under the Plan shall be deemed to be
modified to the extent necessary to satisfy this Paragraph (b).

         4.  Offering Periods. The Plan shall be implemented by a series of
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Offering Periods, with a new Offering Period commencing on April 1 and October 1
of each year or the first business day thereafter (or at such other time or
times as may be determined by the Board of Directors). The initial Offering
Period shall commence on the date on which the Securities and Exchange
Commission declares effective the registration statement on Form S-1 for the
initial public offering of the Company's Common Stock (the "Registration
Statement") and shall end on September 28, 2001 (the "Initial Offering Period").
The Plan shall continue until terminated in accordance with Paragraph 19 hereof.
The Board of Directors of the Company shall have the power to change the
duration and/or the frequency of Offering Periods with respect to future
offerings without stockholder approval if such change is announced at least 15
days prior to the scheduled beginning of the first Offering Period to be
affected.

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         5.  Participation.
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         (a) Except as set forth in Paragraph 26 for the Initial Offering
Period, an eligible Employee may become a participant in the Plan by completing
an Enrollment Form provided by the Company and filing it with the Company or its
designee prior to the applicable Offering Date, unless a later time for filing
the Enrollment Form is set by the Board for all eligible Employees with respect
to a given Offering Period. The Enrollment Form and its submission may be
electronic, as directed by the Company. The Enrollment Form shall set forth the
percentage of the participant's Compensation (which shall be not less than 1%
and not more than 10%) to be paid as Contributions pursuant to the Plan.

         (b) Except as set forth in Paragraph 26 for the Initial Offering
Period, payroll deductions shall commence on the first payroll following the
Offering Date, unless a later time is set by the Board with respect to a given
Offering Period, and shall end on the last payroll paid on or prior to the
Exercise Date of the Offering Periods to which the Enrollment Form is
applicable, unless sooner terminated by the participant as provided in Paragraph
10.

         6.  Method of Payment of Contributions.
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         (a) The participant shall elect to have payroll deductions made on each
payday during the Offering Period in an amount not less than 1% and not more
than 10% of such participant's Compensation on each such payday; provided that
the aggregate of such payroll deductions during the Offering Period shall not
exceed 10% of the participant's aggregate Compensation during said Offering
Period (or such greater percentage as the Board may establish from time to time
before an Offering Date). All payroll deductions made by a participant shall be
credited to his or her account under the Plan. A participant may not make any
additional payments into such account.

         (b) A participant may discontinue his or her participation in the Plan
as provided in Paragraph 10, or, on one occasion only during the Offering
Period, may decrease, but may not increase, the rate of his or her Contributions
during the Offering Period by completing and filing with the Company a new
Enrollment Form authorizing a change in the deduction rate. The change in rate
shall be effective as of the beginning of the next payroll period following the
date of the filing of such new Enrollment Form, if the Enrollment Form is
completed at least ten (10) business days prior to such date, and, if not, as of
the beginning of the next succeeding payroll period.

         (c) Notwithstanding the foregoing, to the extent necessary to comply
with Section 423(b)(8) of the Code and Paragraph 3(b) hereof, a participant's
payroll deductions may be decreased to 0% at such time and for so long as the
aggregate of all payroll deductions accumulated with respect to the current
Offering Period and any other Offering Period ending within the current calendar
year equals $21,250. Payroll deductions shall recommence at the rate provided in
such participant's Enrollment Form at the beginning of the first Offering Period
which is scheduled to end in the following calendar year, unless terminated by
the participant as provided in Paragraph 10.

         7.  Grant of Option.
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         (a) On the Offering Date of each Offering Period, each eligible
Employee participating in such Offering Period shall be granted an option to
purchase on the Exercise Date of such Offering Period a number of shares of the
Common Stock determined by dividing such Employee's Contributions accumulated
prior to such Exercise Date and retained in the participant's account as of the
Exercise Date by the lower of (i) 85% of the fair market value of a share of
Common Stock on the Offering Date, or (ii) 85% of the fair market value of a
share of the Common Stock on the Exercise Date; provided however, that such
purchase shall be subject to the limitations set forth in Paragraphs 3(b) and 12
hereof.

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The fair market value of a share of the Common Stock shall be determined
as provided in Paragraph 7(b) herein.

         (b) The option price per share of the shares offered in a given
Offering Period shall be the lower of (i) 85% of the fair market value of a
share of the Common Stock on the Offering Date, or (ii) 85% of the fair market
value of a share of the Common Stock on the Exercise Date. The fair market value
of the Common Stock on a given date shall be determined by the Board based on
the closing sale price of the Common Stock for such date (or, in the event that
the Common Stock is not traded on such date, on the immediately preceding
trading date), as reported by the National Association of Securities Dealers
Automated Quotation (Nasdaq) National Market or, if such price is not reported,
the mean of the bid and asked prices per share of the Common Stock as reported
by Nasdaq or, in the event the Common Stock is listed on a stock exchange, the
fair market value per share shall be the closing sale price on such exchange on
such date (or, in the event that the Common Stock is not traded on such date, on
the immediately preceding trading date), as reported in The Wall Street Journal.
Notwithstanding the foregoing, on the initial Offering Date, the fair market
value of a share of the Common Stock shall be the offering price to the public
as set forth in the final prospectus included with the Registration Statement
filed with the Securities and Exchange Commission pursuant to Rule 424 under the
Securities Act of 1933, as amended.

         8.  Exercise of Option. Unless a participant withdraws from the Plan as
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provided in Paragraph 10, his or her option for the purchase of shares will be
exercised automatically on the Exercise Date of the Offering Period, and the
maximum number of full shares subject to option will be purchased for him or her
at the applicable option price with the accumulated Contributions in his or her
account. If a fractional number of shares results, then such number shall be
rounded down to the next whole number and any unapplied cash shall be carried
forward to the next Exercise Date, unless the participant requests a cash
payment. The shares purchased upon exercise of an option hereunder shall be
deemed to be transferred to the participant on the Exercise Date. During a
participant's lifetime, a participant's option to purchase shares hereunder is
exercisable only by him or her.

         9.  Delivery. Upon the written request of a participant, certificates
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representing the shares purchased upon exercise of an option will be issued as
promptly as practicable after the Exercise Date of each Offering Period to
participants who wish to hold their shares in certificate form. Any cash
remaining in a participant's account under the Plan after a purchase by him or
her of shares at the termination of each Offering Period shall be carried
forward to the next Exercise Date unless the participant requests a cash
payment.

         10. Withdrawal; Termination of Employment.
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         (a) A participant may withdraw all but not less than all the
Contributions credited to his or her account under the Plan at any time prior to
the Exercise Date of the Offering Period by giving written notice to the
Company or its designee. All of the participant's Contributions credited to his
or her account will be paid to him or her promptly after receipt of his or her
notice of withdrawal and his or her option for the current period will be
automatically terminated, and no further Contributions for the purchase of
shares will be made during the Offering Period.

         (b) Upon termination of the participant's Continuous Status as an
Employee prior to the Exercise Date of the Offering Period for any reason,
including retirement or death, the Contributions credited to his or her account
will be returned to him or her or, in the case of his or her death, to the
person or persons entitled thereto under Paragraph 14 hereof, and his or her
option will be automatically terminated.

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         (c) In the event an Employee fails to remain in Continuous Status as an
Employee for at least 20 hours per week during the Offering Period in which the
Employee is a participant, he or she will be deemed to have elected to withdraw
from the Plan and the Contributions credited to his or her account will be
returned to him or her and his or her option terminated.

         (d) A participant's withdrawal from an Offering Period will not have
any effect upon his or her eligibility to participate in a succeeding offering
or in any similar plan which may hereafter be adopted by the Company.

         11. Interest. No interest shall accrue on the Contributions of a
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participant in the Plan.

         12. Stock.
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         (a) The maximum number of shares of Common Stock which shall be made
available for sale under the Plan shall be 500,000 shares, subject to adjustment
upon changes in capitalization of the Company as provided in Paragraph 18. If
the total number of shares which would otherwise be subject to options granted
pursuant to Paragraph 7(a) hereof on the Offering Date of an Offering Period
exceeds the number of shares then available under the Plan (after deduction of
all shares for which options have been exercised or are then outstanding), the
Company shall make a pro rata allocation of the shares remaining available for
option grants in as uniform a manner as shall be practicable and as it shall
determine to be equitable. Any amounts remaining in an Employee's account not
applied to the purchase of stock pursuant to this Paragraph 12 shall be refunded
on or promptly after the Exercise Date. In such event, the Company shall give
written notice of such reduction of the number of shares subject to the option
to each Employee affected thereby and shall similarly reduce the rate of
Contributions, if necessary.

         (b) The participant will have no interest or voting right in shares
covered by his or her option until such option has been exercised.

         13. Administration. The Board shall supervise and administer the Plan
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and shall have full power to adopt, amend and rescind any rules deemed desirable
and appropriate for the administration of the Plan and not inconsistent with the
Plan, to construe and interpret the Plan, and to make all other determinations
necessary or advisable for the administration of the Plan.

         14. Designation of Beneficiary.
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         (a) A participant may designate a beneficiary who is to receive any
shares and cash, if any, from the participant's account under the Plan in the
event of such participant's death subsequent to the end of the Offering Period
but prior to delivery to him or her of such shares and cash. In addition, a
participant may designate of a beneficiary who is to receive any cash from the
participant's account under the Plan in the event of such participant's death
prior to the Exercise Date of the Offering Period. If a participant is married
and the designated beneficiary is not the spouse, spousal consent shall be
required for such designation to be effective. Beneficiary designations shall be
made either in writing or by electronic delivery as directed by the Company.

         (b) Such designation of beneficiary may be changed by the participant
(and his or her spouse, if any) at any time by submission of the required
notice, which may be electronic. In the event of the death of a participant and
in the absence of a beneficiary validly designated under the Plan who is living
at the time of such participant's death, the Company shall deliver such shares
and/or cash to the executor or administrator of the estate of the participant,
or if no such executor or administrator has been appointed (to the knowledge of
the Company), the Company, in its discretion, may deliver such shares and/or
cash to the spouse or to any one or more dependents or relatives of the
participant, or if no spouse, dependent or relative is known to the Company,
then to such other person as the Company may designate.

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         15. Transferability. Neither Contributions credited to a participant's
             ---------------
account nor any rights with regard to the exercise of an option or to receive
shares under the Plan may be assigned, transferred, pledged or otherwise
disposed of in any way (other than by will, the laws of descent and distribution
or as provided in Paragraph 14 hereof) by the participant. Any such attempt at
assignment, transfer, pledge or other disposition shall be without effect,
except that the Company may treat such act as an election to withdraw funds in
accordance with Paragraph 10 hereof.

         16. Use of Funds. All Contributions received or held by the Company
             ------------
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such Contributions.

         17. Reports. Individual accounts will be maintained for each
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participant in the Plan. Statements of account will be given to participating
Employees promptly following the Exercise Date, which statements will set forth
the amounts of Contributions, the per share purchase price, the number of shares
purchased and the remaining cash balance, if any.

         18. Adjustments Upon Changes in Capitalization. Subject to any required
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action by the stockholders of the Company, the number of shares of Common Stock
covered by unexercised options under the Plan and the number of shares of Common
Stock which have been authorized for issuance under the Plan but are not yet
subject to options (collectively, the "Reserves"), as well as the price per
share of Common Stock covered by each unexercised option under the Plan, shall
be proportionately adjusted for any increase or decrease in the number of issued
shares of Common Stock resulting from a stock split, reverse stock split, stock
dividend, combination or reclassification of the Common Stock, or any other
increase or decrease in the number of shares of Common Stock effected without
receipt of consideration by the Company; provided, however, that conversion of
any convertible securities of the Company shall not be deemed to have been
"effected without receipt of consideration." Such adjustment shall be made by
the Board, whose determination in that respect shall be final, binding and
conclusive. Except as expressly provided herein, no issue 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 of Common Stock subject to an option.

         In the event of the proposed dissolution or liquidation of the Company,
an Offering Period then in progress will terminate immediately prior to the
consummation of such proposed action, unless otherwise provided by the Board. In
the event of a proposed sale of all or substantially all of the assets of the
Company, or the merger, consolidation or other capital reorganization of the
Company with or into another corporation, each option outstanding under the Plan
shall be assumed or an equivalent option shall be substituted by such successor
corporation or a parent or subsidiary of such successor corporation, unless the
Board determines, in the exercise of its sole discretion and in lieu of such
assumption or substitution, to shorten the Offering Period then in progress by
setting a new Exercise Date (the "New Exercise Date"). If the Board shortens the
Offering Period then in progress in lieu of assumption or substitution in the
event of a merger or sale of assets, the Board shall notify each participant in
writing, at least ten days prior to the New Exercise Date, that the Exercise
Date for his or her option has been changed to the New Exercise Date and that
his or her option will be exercised automatically on the New Exercise Date,
unless prior to such date he or she has withdrawn from the Offering Period as
provided in Paragraph 10 hereof. For purposes of this paragraph, an option
granted under the Plan shall be deemed to be assumed if, following the sale of
assets or merger, the option confers the right to purchase, for each share of
Common Stock subject to the option immediately prior to the sale of assets or
merger, the consideration (whether stock, cash or other securities or property)
received in the sale of assets or merger by holders of Common Stock for each
share of Common Stock held on the effective date of the transaction (and if such
holders were offered a choice of consideration, the type of consideration chosen
by the holders of a majority of the outstanding shares of Common Stock);
provided,
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however, that if such consideration received in the sale of assets or merger was
not solely common stock of the successor corporation or its parent (as defined
in Section 424(e) of the Code), the Board may, with the consent of the successor
corporation, provide for the consideration to be received upon exercise of the
option to be solely common stock of the successor corporation or its parent
equal in fair market value to the per share consideration received by holders of
Common Stock in the sale of assets or merger.

         The Board may, if it so determines in the exercise of its sole
discretion, also make provision for adjusting the Reserves, as well as the price
per share of Common Stock covered by each outstanding option, in the event that
the Company effects one or more reorganizations, recapitalizations, rights
offerings or other increases or reductions of shares of its outstanding Common
Stock, and in the event of the Company being consolidated with or merged into
any other corporation.

         19. Amendment or Termination.
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         (a)  The Board may at any time terminate or amend the Plan. Except as
provided in Paragraph 18 hereof, no such termination may affect options
previously granted, nor may an amendment make any change in any option
theretofore granted which adversely affects the rights of any participant. In
addition, to the extent necessary to comply with Section 423 of the Code (or any
successor rule or provision or any applicable law or regulation), the Company
shall obtain stockholder approval in such a manner and to such a degree as so
required.

         (b) Without stockholder consent and without regard to whether any
participant rights may be considered to have been adversely affected, the Board
shall be entitled to change the Offering Periods, limit the frequency and/or
number of changes in the amount withheld during an Offering Period, establish
the exchange ratio applicable to amounts withheld in a currency other than U.S.
dollars, permit payroll withholding in excess of the amount designated by a
participant in order to adjust for delays and mistakes in the Company's
processing of properly completed withholding elections, establish reasonable
waiting and adjustment periods and/or accounting and crediting procedures to
ensure that amounts applied toward the purchase of Common Stock for each
participant properly correspond with amounts withheld from the participant's
Compensation, and establish such other limitations or procedures as the Board in
its sole discretion decides are consistent with the Plan.

         20. Notices. All notices or other communications by a participant to
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the Company under or in connection with the Plan shall be deemed to have been
duly given when received in the form specified by the Company at the location,
or by the person, designated by the Company for the receipt thereof.

         21. Conditions Upon Issuance of Shares. Shares shall not be issued with
             ----------------------------------
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto shall comply with all applicable
provisions of law, domestic or foreign, including, without limitation, the
Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as
amended, the rules and regulations promulgated thereunder, and the requirements
of any stock exchange upon which the shares may then be listed, and shall be
further subject to the approval of counsel for the Company with respect to such
compliance.

         As a condition to the exercise of an option, the Company may require
the person exercising such option to represent and warrant at the time of any
such exercise that the shares are being purchased only for investment and
without any present intention to sell or distribute such shares if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned applicable provisions of law.

         22. Right to Terminate Employment. Nothing in the Plan or in any
             -----------------------------
agreement entered into pursuant to the Plan shall confer upon any Employee or
other optionee the right to continue in the employment of the Company or any
Subsidiary, or affect any right which the Company or any Subsidiary may have to
terminate the employment of such Employee or other optionee.

         23. Rights as a Stockholder. Neither the granting of an option nor a
             -----------------------
deduction from payroll shall constitute an Employee the owner of shares covered
by an option. No optionee shall have any right as a stockholder unless and until
an option has been exercised, and the shares underlying the option have been
registered in the Company's share register.

         24. Term of Plan. The Plan became effective upon its adoption by the
             ------------
Board of Directors on October 3, 2000 and shall continue in effect for a term of
ten (10) years unless sooner terminated under Paragraph 19 hereof.

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         25. Applicable Law. This Plan shall be governed in accordance with the
             --------------
laws of the State of Delaware, applied without giving effect to any conflict-of-
law principles.

         26. Special Provisions for Initial Offering Period. The following
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provisions of this Paragraph 26 shall apply with respect to the Initial Offering
Period notwithstanding any provision of the Plan to the contrary:

         (a) Every eligible Employee shall automatically become a participant in
the Plan for the Initial Offering Period at the highest percentage of
Compensation permitted under Paragraph 6. No payroll deductions shall be
required for the Initial Offering Period; however, a participant may, at any
time after the effectiveness of the Plan's registration statement on Form S-8,
elect to have payroll deductions up to the aggregate amount which would have
been credited to his or her account if a deduction of ten percent (10%) of the
Compensation which he or she received on each pay day during the Initial
Offering Period had been made (the "Maximum Amount") or decline to participate
by giving written notice to the Company.

         (b) Upon the automatic exercise of a participant's option on the
Exercise Date for the Initial Offering Period, a participant shall be permitted
to purchase shares with (i) the accumulated payroll deductions in his or her
account, if any, (ii) a direct payment from the participant, or (iii) a
combination thereof; provided, however that the total amount applied to the
purchase may not exceed the lesser of (1) Maximum Amount or (2) such amount as
is necessary to comply with Paragraph 6(c) hereof.

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