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                                                                    Exhibit 4.31

                         CONTROL DELIVERY SYSTEMS, INC.
                               2001 INCENTIVE PLAN

                        Restricted Stock Award Agreement

     The undersigned employee ("Employee") has been granted an award (the
"Award") of restricted stock from Control Delivery Systems, Inc. (the "Company")
under the 2001 Incentive Plan (the "Plan"), subject to the terms set forth below
and in the Plan, a copy of which as currently in effect has been delivered to
Employee. In consideration of the grant of the Award, the Employee agrees with
the Company as follows:

1. Effective Date. This Agreement shall take effect as of the date of grant of
the Award, as indicated on the signature page hereof.

2. Shares Subject to Award. The Award consists of the number of shares set forth
on the signature page hereof (the "Shares") of common stock of the Company
("Stock"). Employee's rights to the Shares are subject to the restrictions
described in this Agreement and the Plan in addition to such other restrictions,
if any, as may be imposed by law.

3. Meaning of Certain Terms. Except as otherwise expressly provided, all terms
used herein shall have the same meaning as in the Plan. The term "vest" as used
herein with respect to any Share means the lapsing of the restrictions described
herein with respect to such Share.

4. Nontransferability of Shares. The Shares cannot be sold, transferred,
pledged, assigned or otherwise encumbered or disposed of until they have vested,
and then only as provided below and in the Plan.

5. Forfeiture Risk. If Employee ceases to be employed by the Company and its
subsidiaries for any reason, including death, any then outstanding and unvested
Shares shall be automatically and immediately forfeited. Employee hereby (i)
appoints the Company as the attorney-in-fact of Employee to take such actions as
may be necessary or appropriate to effectuate a transfer of the record ownership
of any such shares that are unvested and forfeited hereunder, (ii) agrees to
deliver to the Company, as a precondition to the issuance of any certificate or
certificates with respect to unvested Shares hereunder, one or more stock
powers, endorsed in blank, with respect to such Shares, and (iii) agrees to sign
such other powers and take such other actions as the Company may reasonably
request to accomplish the transfer or forfeiture of any unvested Shares that are
forfeited hereunder.

6. Vesting of Shares. The Shares shall vest in accordance with the provisions of
this Paragraph 6 and applicable provisions of the Plan (if not earlier in
accordance with the Plan, including Section 6 of the Plan), as follows:

     100% of the Shares will vest on the earlier to occur of:

          -    October 7, 2005; or

          -    a Liquidity Event Date (as defined below).


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     Notwithstanding the foregoing, in the event that a Liquidity Event Date
that relates to an initial public offering occurs on or before October 7, 2005,
100% of the Shares shall vest on that date which is the six-month anniversary of
the closing of the initial public offering.

     Any securities of the Company or any other entity, and any cash and other
consideration, into which the Shares are converted or for which they are
exchanged, by reason of a merger, consolidation, sale of assets, reorganization
or other transaction, shall vest (by their terms or through the use of an
escrow, a commitment to deliver in the future or such other device as is
determined by the administrator of the Plan) on the same terms as the Shares
from which they were converted or for which they were exchanged.

     A "Liquidity Event" means any public offering, merger, consolidation, sale
of assets, reorganization or other transaction in or as a result of which the
Stock of the Company (or the stock or other securities into or for which such
Stock is converted or exchanged) are or become registered under the Securities
Exchange Act of 1934 or are converted into or exchanged for cash. "Liquidity
Event Date" shall mean the date of the closing of a Liquidity Event.

     Notwithstanding the foregoing, no Shares shall vest on any vesting date
specified above unless Employee is then, and since the date of grant has
continuously been, employed by the Company or its subsidiaries.

7. Legend. Any certificates representing unvested Shares shall bear a legend
substantially in the following form:

     THE TRANSFERABILITY OF THIS CERTIFICATE AND THE SHARES OF STOCK REPRESENTED
     HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS (INCLUDING FORFEITURE) OF AN
     INCENTIVE PLAN AND A RESTRICTED STOCK AWARD AGREEMENT ENTERED INTO BETWEEN
     THE REGISTERED OWNER AND CONTROL DELIVERY SYSTEMS, INC. COPIES OF SUCH PLAN
     AND AGREEMENT ARE ON FILE IN THE OFFICES OF CONTROL DELIVERY SYSTEMS, INC.

     As soon as practicable following the vesting of any such Shares, the
Company shall cause a certificate or certificates covering such Shares to be
issued and delivered to Employee, containing a legend substantially in the
following form:

     THE SHARES OF STOCK REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
     RESTRICTIONS UPON TRANSFER SET FORTH IN A RESTRICTED STOCK AWARD AGREEMENT.
     THE CORPORATION WILL FURNISH A COPY OF SUCH AGREEMENT TO THE HOLDER OF THIS
     CERTIFICATE UPON WRITTEN REQUEST AND WITHOUT CHARGE.

     If any Shares are held in book-entry form, the Company may take such steps
as it deems necessary or appropriate to record and manifest the restrictions
applicable to such Shares.

8. Dividends, etc. Employee shall be entitled to (i) receive regular cash
dividends, if any, paid with respect to those Shares of which Employee is the
record owner on the record date for


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such dividend, and (ii) vote any Shares of which Employee is the record owner on
the record date for such vote. Any dividends and distributions (other than any
regular cash dividends) distributed with respect to any Shares or any securities
of the Company or any other entity into which the Shares are converted or for
which they are exchanged (the "associated share"), including without limitation
a distribution of stock by reason of a stock dividend, stock split or otherwise
with respect to an associated share, or a distribution of other securities with
respect to an associated share, shall be subject to the restrictions of this
Agreement in the same manner and for so long as the associated share remains
subject to such restrictions, and shall be forfeited if and when the associated
share is so forfeited. The administrator of the Plan may require that any cash
distribution with respect to the Shares other than a regular cash dividend be
placed in escrow or otherwise made subject to such restrictions as the
administrator of the Plan deems appropriate. References in this Agreement to the
Shares shall refer, with the necessary changes having been made, to any such
restricted amounts.

9. Restriction on Transfer of Vested Shares.

     a. Employee shall not sell, assign, transfer, pledge, hypothecate, give or
otherwise dispose of, by operation of law or otherwise (collectively
"transfer"), any of the Shares once they have vested ("Vested Shares"), or any
interest therein, unless such transfer shall be made in compliance with the
provisions of this Section 9 and the provisions of Sections 10 and 11 of this
Agreement.

     b. Notwithstanding Section 10 hereof, Employee shall not transfer any
Vested Shares unless either (i) a registration statement under the Securities
Act of 1933, as amended (the "Act"), with respect to the Vested Shares shall
have become, and continues to be, effective, or (ii) the Company receives an
opinion of counsel reasonably satisfactory to it that registration of such
Vested Shares is not required under the Act.

10. Right of First Refusal on Dispositions of Vested Shares.

     a. Receipt of Third-Party Offer. If at any time Employee desires to sell
for cash, cash equivalents or any other form of consideration (including a
promissory note) Vested Shares pursuant to an offer or proposed offer from a
third party (the "Proposed Transferee"), Employee shall submit a written offer
(the "Offer") to sell such Vested Shares (the "Offered Shares") to the Company
on terms and conditions, including price, not less favorable to the Company than
those on which Employee proposes to sell such Offered Shares to the Proposed
Transferee. The Offer shall disclose the identity of the Proposed Transferee,
the number of Offered Shares proposed to be sold, the total number of Vested
Shares owned by Employee, the terms and conditions, including price, of the
proposed sale, and any other material facts relating to the proposed sale. The
Offer shall further state that the Company may acquire, in accordance with the
provisions of this Agreement, all or any portion of the Offered Shares for the
price and upon the other terms and conditions, including deferred payment (if
applicable), set forth therein.

     b. Company Notice of Intent to Purchase. If the Company desires to purchase
all or any portion of the Offered Shares, the Company shall give to Employee
written notice of the number of Offered Shares to be purchased by it within 30
days of the date of the Offer. Such communication shall, when taken in
conjunction with the Offer, be deemed to constitute a valid,


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legally binding and enforceable agreement for the sale and purchase of the
Offered Shares. Sale of the Offered Shares to the Company pursuant to this
Section 10 shall be made at the offices of the Company on the 45th day following
the date of the Offer (or, if such day is not a business day, then on the next
succeeding business day). Such sale shall be effected by Employee's delivery to
the Company of a certificate or certificates evidencing the Offered Shares to be
purchased by the Company, duly endorsed for transfer to the Company, against
payment to Employee of the purchase price therefor by the Company by a certified
or cashier's check.

     c. Sale to Third Party. If, within 30 days of its receipt of notice of the
Offer, the Company fails to deliver written notice to Employee of its intention
to purchase all of the Offered Shares (the Offered Shares which the Company does
not elect to purchase being referred to as the "Refused Shares"), the Refused
Shares not so purchased may be sold by Employee at any time within 90 days after
the date of the Offer, at not less than the price and upon other terms and
conditions, if any, not more favorable to the Proposed Transferee than those
specified in the Offer. If the Refused Shares are not sold within such 90 day
period, they shall continue to be subject to the requirements of a prior offer
pursuant to this Section 10. If the Refused Shares are sold pursuant to this
Section 10 to any purchaser who is not a party to an agreement with the Company
containing restrictions on the transfer of the Vested Shares to the same extent
as those contained herein, the Company, may at its option, require the purchaser
to execute and deliver an agreement containing restrictions on the transfer of
Vested Shares the same as those set forth in this Agreement.

     d. Permitted Transfers. Employee shall have the right to make Permitted
Transfers (as defined below) of Employee's Vested Shares and the provisions of
subsections (a), (b) and (c) above shall not apply to any such Permitted
Transfer by Employee. For purposes of this Agreement, "Permitted Transfer" shall
mean any transfer by Employee during his or her lifetime of all or any portion
of the Vested Shares (i) to the Company; or (ii) to any parent, spouse, child,
grandchild, brother, sister or the spouse of a child, grandchild, brother or
sister (a "Member of the Immediate Family") of Employee, to a trust created for
the benefit of a Member of the Immediate Family of Employee or to a custodian of
a property of one or more such persons, or to a limited partnership or limited
liability company all partners or members of which are Members of the Immediate
Family of Employee, any of such transfers to include transfers by will or the
laws of descent and distribution; provided, however, that, it shall be a
condition of each such transfer, that (x) the transferee agrees to be bound by
the terms of this Agreement, including without limitation Sections 10, 11 and
13, as though no such transfer had taken place, and that (y) Employee has
complied with all applicable laws in connection with such transfer.


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11. Right of Repurchase of Vested Shares.

     a. Termination of Employment Relationship. If Employee's employment or
other service relationship with the Company terminates, voluntarily or
involuntarily, for any reason, the Company shall have the right to purchase, and
Employee (or Employee's legal representative or transferee(s) pursuant to
Section 10(d) of this Agreement) shall, at the election of the Company, be
obligated to sell, all or any part of Employee's Vested Shares at the purchase
price and on the terms provided in this Section 11 (the "Repurchase Right").

     b. Exercise of Repurchase Right. The Company may exercise the Repurchase
Right by giving to Employee (or Employee's legal representative or transferee(s)
pursuant to Section 10(d) of this Agreement), within 30 days of the date on
which Employee's employment or other service relationship with the Company
terminates (the "Termination Date"), written notice of (i) the number of Vested
Shares to be purchased by it, and (ii) the purchase price, as determined in a
manner provided below, to be paid for such Vested Shares. Such communication
shall be deemed to constitute a valid, legally binding and enforceable agreement
for the sale and purchase of the Vested Shares.

     The purchase price of Vested Shares purchased by the Company pursuant to
this Section 11 shall be the fair market value of such Vested Shares on the
Termination Date, as conclusively determined by the Board of Directors of the
Company after taking into consideration such factors as it deems appropriate.

     Sale of the Vested Shares to the Company pursuant to this Section 11 shall
be made at the offices of the Company on the 45th day following the Termination
Date (or, if such day is not a business day, then on the next succeeding
business day) or such earlier business day of which the Company shall notify
Employee (or Employee's legal representative or transferee(s) pursuant to
Section 10(d) of this Agreement). Such sale shall be effected by the delivery to
the Company of a certificate or certificates evidencing the Vested Shares to be
purchased by the Company, duly endorsed for transfer to the Company, against
payment to Employee (or Employee's legal representative or transferee(s)
pursuant to Section 10(d) of this Agreement) of the purchase price therefor by
the Company by a certified or cashier's check.

12. Effect of Prohibited Transfer. The Company shall not be required (a) to
transfer on its books any Shares which shall have been sold or transferred in
violation of any of the provisions set forth in this Agreement, or (b) to treat
as owner of such Shares or to pay dividends to any transferee to whom any such
Shares shall have been so sold or transferred.

13. Initial Public Offering. Upon the closing of the first underwritten public
offering by the Company under the Act of its Stock for its own account for cash:
(a) Sections 9(a), 10 and 11 of this Agreement shall terminate except as to
Offers accepted and Repurchase Rights exercised by the Company prior to such
date; (b) without the prior written approval of the Company, Employee agrees not
to, directly or indirectly, make or cause any offering, sale, short sale,
hypothecation, pledge or other disposition of any Vested Shares until the date
180 days after the effective date of the registration statement filed with the
Securities and Exchange Commission pursuant to the Act by the Company in
connection with such offering (the "Holdback Period"); and (c) Employee shall,
if so requested by the Company, sign an agreement with the


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underwriters of the offering containing such terms and provisions requested by
such underwriters substantially similar to those contained in this Section 13.
The Company may impose stop-transfer instructions with respect to the Shares or
other securities subject to the foregoing restrictions until the end of the
Holdback Period.

14. Termination of Restrictions on Transfer. The restrictions on the transfer of
Vested Shares contained in Sections 11 through 13 of this Agreement, and the
obligations of Employee and the Company set forth therein, except as to Offers
accepted and Repurchase Rights exercised by the Company prior to a Change in
Control, shall terminate upon a Change in Control, as defined below. The
transfer of the Shares pursuant to a Change in Control shall not be subject to
the provisions of Sections 9(a) and 10 of this Agreement.

     For purposes of this Section 14, Change in Control shall mean:

     (i) the acquisition by any Person or group of the ultimate beneficial
ownership (within the meaning of Rule 13d-3 promulgated under the Securities
Exchange Act of 1934, as amended (the "Exchange Act")) of more than 50% of the
then outstanding securities of the Company entitled to vote generally in the
election of directors; excluding, however, the following: (A) any acquisition
directly from the Company (excluding any acquisition by virtue of the exercise
of an exercise, conversion or exchange privilege unless the security being so
exercised, converted or exchanged was itself acquired directly from the
Company), (B) any acquisition by the Company, or (C) any acquisition by an
employee benefit plan (or related trust) sponsored or maintained by the Company
or by any corporation controlled by the Company; or

     (ii) a reorganization, recapitalization, merger or consolidation (a
"Corporate Transaction") of the Company, unless securities representing more
than 50% of the then outstanding securities entitled to vote generally in the
election of directors of the Company or the corporation resulting from or
surviving such Corporate Transaction (or the ultimate parent of the Company or
such corporation after such Corporate Transaction) are beneficially owned
subsequent to such Corporate Transaction by the Person or Persons who were the
beneficial owners of the outstanding securities of the Company entitled to vote
generally in the election of directors immediately prior to such Corporate
Transaction, in substantially the same proportions as their ownership
immediately prior to such Corporate Transaction; or

     (iii) the sale, transfer or other disposition of all or substantially all
of the assets of the Company; or

     (iv) the dissolution or liquidation of the Company.

     For purposes of this definition, securities entitled to vote generally in
the election of directors that are issuable upon exercise of an exercise,
conversion or exchange privilege shall be deemed to be outstanding. In addition,
for purposes of this definition the following terms have the meanings set forth
below:

     A Person will be deemed to be the "owner" of any securities of which such
Person would be the "beneficial owner," as such term is defined in Rule 13d-3
promulgated by the Securities and Exchange Commission under the Exchange Act.


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     "Person" has the meaning used in Section 13(d) of the Exchange Act, except
that "Person" does not include the Company or a wholly owned subsidiary of the
Company or an employee benefit plan (or related trust) of the Company or of a
wholly owned subsidiary.

15. Certain Tax Matters. Employee expressly acknowledges the following:

     a. Employee has been advised to confer promptly with a professional tax
advisor to consider whether Employee should make a so-called "83(b) election"
with respect to the Shares. Any such election, to be effective, must be made in
accordance with applicable regulations and within thirty (30) days following the
date of this Award. The Company has made no recommendation to Employee with
respect to the advisability of making such an election.

     b. The award or vesting of the Shares acquired hereunder, and the payment
of dividends with respect to such Shares, may give rise to "wages" subject to
withholding. Employee expressly acknowledges and agrees that Employee's rights
hereunder are subject to Employee's promptly paying to the Company in cash (or
by such other means as may be acceptable to the Company in its discretion,
including, if the administrator of the Plan so determines, by the delivery of
previously acquired Stock or shares of Stock acquired hereunder or by the
withholding of amounts from any payment hereunder) all taxes required to be
withheld in connection with such award, vesting or payment.

16. No Employment Rights. Nothing in the Plan, the Award or this Agreement
confers upon the Employee any right to continued employment or interferes with
the right of the Company to terminate Employee's employment at any time.

17. Severability; Governing Law. If any provisions of this Agreement shall be
determined to be illegal or unenforceable by any court of law, the remaining
provisions shall be severable and enforceable in accordance with their terms.
This Agreement shall be governed by, and construed in accordance with, the laws
of Delaware, excluding its choice of law provisions.

18. Injunctive Relief. It is acknowledged that it will be impossible to measure
the damages that would be suffered by the Company if Employee fails to comply
with the provisions of this Agreement and that, in the event of any such
failure, the Company will not have an adequate remedy at law. The Company shall,
therefore, be entitled to obtain specific performance of each of Employee's
obligations hereunder and to obtain immediate injunctive relief without the
requirement of posting a bond. Employee shall not urge, as a defense to any
proceeding for such specific performance or injunctive relief, that the Company
has an adequate remedy at law.

19. Binding Effect. This Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective heirs, executors,
administrators, successors and permitted assigns.

20. Amendments. Except as provided below, the Board may at any time or times
amend the Plan or this Agreement for the purpose of satisfying the requirements
of any changes in applicable laws or regulations or for any other purpose which
at the time may be permitted by law. Sections 9 through 11 of this Agreement,
containing restrictions on the transfer of Shares, may be amended or modified
only by a written instrument executed by both the Company and Employee. No
termination or amendment of the Plan or amendment of this Agreement shall,


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without Employee's consent, adversely affect Employee's rights under the Plan or
this Agreement.

21. Notices. All notices required or permitted hereunder shall be in writing and
deemed effectively given upon personal delivery, upon deposit with the United
States Post Office, by registered or certified mail, postage prepaid, or upon
deposit with a recognized express overnight courier service, addressed, if to
the Company, to 400 Pleasant Street, Watertown, MA 02472, attention: Chief
Financial Officer, and if to Employee, to the address shown beneath his or her
respective signature to this Agreement, or at such other address or addresses as
either party shall designate to the other in accordance with this Section 21.

22. Merger Provision. This Agreement, including the Plan which is incorporated
herein by reference in its entirety, constitutes the entire agreement between
the parties hereto pertaining to the subject matter hereof and supersedes all
prior and contemporaneous agreements and understandings, whether oral or
written, of the parties hereto concerning the subject matter hereof.

23. Waivers. Any provision contained in this Agreement may be waived, either
generally or in any particular instance, by the Company.

24. Definition. As used in this Agreement, the term "Company" shall include any
subsidiary or parent of the Company as defined in Sections 424(e) and (f) of the
Code.

25. Consistency with Plan. If there is any inconsistency between the provisions
of this Agreement and the provisions of the Plan, the Plan shall control.

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Name of Employee: Lori Freedman

Number of Shares of Restricted Stock granted: 20,000

Date of Grant: August 16, 2004

The foregoing Restricted Stock Award is hereby accepted and in consideration of
the grant of such Award, the undersigned Employee hereby agrees with Control
Delivery Systems, Inc. that the undersigned will be bound by the foregoing
Restricted Stock Award Agreement:


/s/ Lori Freedman
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(Signature of Employee)

Dated: _________, 2004