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                                                                   Exhibit 10.20
                               IROBOT CORPORATION

                             NON-EMPLOYEE DIRECTORS'
                          DEFERRED COMPENSATION PROGRAM

I. INTRODUCTION

      The iRobot Corporation Non-Employee Directors' Deferred Compensation
Program (the "Program"), effective January 1, 2006, is established pursuant to
the iRobot Corporation 2005 Stock Option and Incentive Plan (the "Plan") and
permits a Director who is not an employee of the Company (a "Non-Employee
Director") to defer receipt of all or any part of the compensation payable to
him under the Plan.

II. ADMINISTRATION

      The Program shall be administered by the Compensation Committee of the
Board of Directors of the Company (the "Committee"). The Committee shall have
complete discretion and authority with respect to the Program and its
application, except as expressly limited by the Program.

III. ELIGIBILITY

      All Non-Employee Directors are eligible to participate in the Program.

IV. DEFERRAL OF RETAINER FEES

      A. Election to Defer. A Non-Employee Director may elect in advance to
defer the receipt of some or all of his retainer fees from the Company. To make
such an election, the Non-Employee Director must execute and deliver to the
Committee an election form specifying the percentage of his retainer fees he
wishes to defer. Except with respect to a newly elected or appointed
Non-Employee Director, any election under this paragraph shall apply only to
retainer fees that are earned with respect to services to be performed beginning
on or after the start of


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the next calendar year after such receipt and acceptance. A newly elected or
appointed Non-Employee Director, may, within 30 days of becoming a Non-Employee
Director, file a deferral election which shall apply only to retainer fees that
are earned with respect to services to be performed subsequent to the election.
An election shall remain in effect from year to year, until a new election
becomes effective with respect to retainer fees payable in the next calendar
year. A Non-Employee Director may revoke his deferral election with respect to
retainer fees that are payable in the calendar year beginning after receipt and
acceptance by the Company of his written revocation.

      B. Deferred Account. As of the last day of each calendar quarter, a
Non-Employee Director's deferred account ("Account") shall be credited with a
number of whole and fractional stock units determined by dividing his deferred
retainer fees for the calendar quarter by the fair market value of a share of
common stock, par value $0.01 per share, of the Company ("Stock"). For purposes
of this Program, "fair market value" of a share of Stock on any given date shall
mean the last reported sale price at which Stock is traded on such date, or if
no Stock is traded on such date, the most recent date on which Stock was traded
on the NASDAQ National Market System, of if applicable, any other national stock
exchange on which Stock is traded.

      C. Dividend Equivalent Amounts. Whenever dividends (other than dividends
payable only in shares of Stock) are paid with respect to Stock, each Account
shall be credited with a number of whole and fractional stock units determined
by multiplying the dividend value per share by the stock unit balance of the
Account on the record date and dividing the result by the fair market value of a
share of Stock on the dividend payment date.

      D. Period of Deferral. Each Non-Employee Director making an election
pursuant to Paragraph IV.A shall specify the deferral period applicable to his
Account. Such period shall be


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either (i) a specified number of years after the date such specification is made
by the Non-Employee Director or (ii) until the Non-Employee Director's
termination of membership on the Board of Directors of the Company. A
Non-Employee Director may change his election with regard to a period of
deferral, but (a) the new election may not take effect until at least 12 months
after the date on which the new election is made, (b) the distribution must be
deferred for a period of not less than five years from the date of the
originally scheduled distribution, and (c) the new election must be made not
less than 12 months prior to the date of the originally scheduled distribution.

      E. Designation of Beneficiary. A Non-Employee Director may designate one
or more beneficiaries to receive payments from his Account in the event of his
death. A designation of beneficiary shall apply to a specified percentage of a
Non-Employee Director's entire interest in his Account. Such designation, or any
change therein, must be in writing and shall be effective upon receipt by the
Company. If there is no effective designation of beneficiary, or if no
beneficiary survives the Non-Employee Director, the estate of the Non-Employee
Director shall be deemed to be the beneficiary. All payments to a beneficiary or
estate shall be made in a lump sum in shares of Stock, with any fractional share
paid in cash.

      F. Payment. All amounts credited to a Non-Employee Director's Account
shall be paid in shares of Stock to the Non-Employee Director, or his designated
beneficiary (or beneficiaries) or estate, in a lump sum at the end of the
deferral period determined by the deferral election in effect for the Account;
provided, however, that fractional shares shall be paid in cash. Notwithstanding
the foregoing, in the event of a Change in Control Event (as defined in Section
12(c)(i) of the Plan), all Accounts under the Program shall become immediately
payable in a lump sum.


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V. ADJUSTMENTS

      In the event of a stock dividend, stock split or similar change in
capitalization affecting the Stock, the Committee shall make appropriate
adjustments in the number of stock units credited to Non-Employee Directors'
Accounts.

VI. AMENDMENT OR TERMINATION OF PROGRAM

      The Company reserves the right to amend or terminate the Program at any
time, by action of its Board of Directors, provided that no such action shall
adversely affect a Non-Employee Director's right to receive compensation earned
before the date of such action or his rights under the Program with respect to
amounts credited to his Account before the date of such action. In no event
shall the distribution of Accounts to Non-Employee Directors be accelerated by
virtue of any amendment or termination of the Program.

VII. MISCELLANEOUS PROVISIONS

      A. Notices. Any notice required or permitted to be given by the Company or
the Committee pursuant to the Program shall be deemed given when personally
delivered or deposited in the United States mail, registered or certified,
postage prepaid, addressed to the Non-Employee Director at the last address
shown for the Non-Employee Director on the records of the Company.

      B. Nontransferability of Rights. During a Non-Employee Director's
lifetime, any payment under the Program shall be made only to him. No sum or
other interest under the Program shall be subject in any manner to anticipation,
alienation, sale, transfer, assignment, pledge, encumbrance or charge, and any
attempt by a Non-Employee Director or any beneficiary under the Program to do so
shall be void. No interest under the Program shall in any manner be liable for
or subject to the debts, contracts, liabilities, engagements or torts of a
Non-Employee Director or beneficiary entitled thereto.


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      C. Company's Obligations to Be Unfunded and Unsecured. The Accounts
maintained under the Program shall at all times be entirely unfunded, and no
provision shall at any time be made with respect to segregating assets of the
Company (including Stock) for payment of any amounts hereunder. No Non-Employee
Director or other person shall have any interest in any particular assets of the
Company (including Stock) by reason of the right to receive payment under the
Program, and any Non-Employee Director or other person shall have only the
rights of a general unsecured creditor of the Company with respect to any rights
under the Program.

      D. Governing Law. The terms of the Program shall be governed, construed,
administered and regulated in accordance with the laws of the Commonwealth of
Massachusetts. In the event any provision of this Program shall be determined to
be illegal or invalid for any reason, the other provisions shall continue in
full force and effect as if such illegal or invalid provision had never been
included herein.

      E. Effective Date of Program. The Program shall become effective as of
January 1, 2006.


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                               IROBOT CORPORATION

                             NON-EMPLOYEE DIRECTORS'
                                DEFERRAL ELECTION

      1. Pursuant to the iRobot Corporation 2005 Stock Option and Incentive Plan
(the "Plan") and the Deferred Compensation Program established thereunder (the
"Program"), I, the undersigned Director, hereby elect and instruct iRobot
Corporation (the "Company") to defer ______% of any cash retainer fees payable
to me by the Company. I hereby elect to defer receipt of my Directors' fees
until:

      [ ] _______ months from the date of this election.

      [ ] My termination of service as a Director of the Company.

      2. I understand that the amounts credited to my deferred account will be
paid in shares of common stock of the Company in a lump sum on the date
specified in Paragraph 1 above.

      3. I hereby designate the following as my beneficiary (or beneficiaries)
under the Program and hereby revoke any prior designation of beneficiary:

<Table>
<Caption>
Beneficiary Name and Address      Relationship      Social Security No.      Share
----------------------------      ------------      -------------------      -----
<S>                               <C>               <C>                      <C>

----------------------------      ------------      -------------------      -----

----------------------------      ------------      -------------------      -----
</Table>

If a beneficiary predeceases me, his share shall be paid to the other surviving
beneficiaries in equal shares. If no beneficiary survives me or if there is no
effective beneficiary designation, my deferred account shall be paid to my
estate.

      4. I understand that with respect to all amounts credited to my deferred
account, I have no greater rights than that of an unsecured creditor of the
Company.

      5. The election to defer under Paragraph 1 shall apply only to cash fees
that are earned beginning at or after the start of the next calendar year after
such receipt and acceptance, and shall remain in effect for all subsequent years
unless the Company accepts, pursuant to the Plan and the Program, a new
election. I acknowledge that the election to defer and to receive payment in
shares of common stock of the Company may be completely revoked in writing
prospectively with respect to cash fees payable in the calendar year beginning
after the date of revocation.


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              Executed this __________ day of ______________, 2005.



                                          --------------------------------------
                                          Signature

                                          --------------------------------------
                                          Print Name

ACCEPTED:

iROBOT CORPORATION

By:
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Title:
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Date:
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