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                                                                   Exhibit 10.20


(MEMORY LOGO)

MEMORY PHARMACEUTICALS CORP.                            JOANNE LEONARD
100 PHILIPS PARKWAY                                     SENIOR VICE PRESIDENT
MONTVALE, NEW JERSEY 07645                              CHIEF FINANCIAL OFFICER
PHONE: (201) 802-7102
FAX: (201) 802-7190
www.memorypharma.com

December 14,2001

Gardiner F.H. Smith
7913 Brethren Drive
Gaithersburg, MD 20879

Dear Gardiner:

         We are pleased to inform you that both the Board of Directors and
management team of Memory Pharmaceuticals Corp. (the "Company") are impressed
with your experience and accomplishments, and would like to extend an offer to
you to join our Company as Vice President of Business Development. We look
forward to you joining our team, and are confident that you will contribute
significantly to the value of our organization. We are therefore pleased to
provide you with the terms of your anticipated employment by the Company.

         1. Position. Your position will be Vice President of Business
Development, based out of the Company's offices currently located in Montvale,
New Jersey, and will report directly to the Company's Chief Executive Officer.
As Vice President of Business Development, you will be part of the Company's
senior management team, and will work closely with this team to establish
strategic, value-building relationships with pharmaceutical companies and
academic institutions. Your responsibilities shall include, but not be limited
to, securing and overseeing collaborations with corporate partners,
in-licensing and out-licensing activities, management of intellectual property,
and maintenance of a competitor intelligence information database. In addition
to performing duties and responsibilities associated with the position of Vice
President of Business Development, from time to time the Company may assign you
other duties and responsibilities and/or may assign you to a different location.

         As a full-time employee of the Company, you will be expected to devote
your full business time and energies to the business and affairs of the Company.
Your performance will be reviewed formally after six months of employment and
annually thereafter at the end of each calendar year.

         2. Starting Date/Nature of Relationship. It is expected that your
employment will start on January 21, 2002 (the "Start Date"). No provision of
this letter shall be construed to create an express or implied employment
contract for a specific period of time. Either you or the Company may terminate
the employment relationship at any time and for any reason, by giving at least
thirty (30) days' prior written notice to the other party.

         3. Compensation.

         (a) Your initial salary will be at the bi-weekly rate of $7,500.00
(annualized at $195,000).

         (b) You will receive a one-time sign-on bonus of $25,000, payable
within 30 days of your Start Date. This sign-on bonus is fully refundable to the
Company if you leave the Company within twelve months of your Start Date.
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MEMORY PHARMACEUTICALS CORP.
Gardiner F.H. Smith

         (c) You will receive incentive stock options to purchase 140,000 Shares
of Common Stock of Memory Pharmaceuticals Corp. at $0.25 per share, which will
vest in quarterly increments over a period of four (4) years as described in the
Stock Option Agreement, which you and the Company will enter into on or before
the Start Date. You will receive additional incentive stock options to purchase
135,000 Shares of Common Stock of Memory Pharmaceuticals Corp., immediately
after the closing of the Company's Series D Financing at the then fair market
value to be determined by the Company's Board of Directors (without affecting
the purchase price of the initial grant of options to acquire 140,000 shares of
the Company's Common Stock), with such additional option vesting to commence on
the date of such grant in quarterly increments over a period of four (4) years.
The additional incentive stock options to purchase 135,000 Shares are being
provided to allow your percentage ownership before the Series D Financing not to
be substantialty diluted.

         (d) You will be eligible to receive annual bonus payments dependent on
the performance of the Company and your individual performance, subject to the
discretion of the Board of Directors. Your target bonus will be equal to
twenty-five percent (25%) of your base salary, assuming the achievement of such
Company and individual performance objectives.

         (e) Upon termination for any reason, the Company will pay you within
two weeks of such termination, your current base salary earned through the
termination date, plus accrued vacation, if any, and other benefits or payments,
if any, to which you are entitled. In the event you are terminated by the
Company, without "Cause" (as hereinafter defined), then the Company will
continue to pay you your bi-weekly rate in effect at the time of termination and
provide and pay the Company's portion of your medical insurance for a period of
six (6) months. Further, for the period commencing seven months following such
termination and ending twelve months after such termination, the Company will
continue to pay you your bi-weekly rate in effect at the time of termination and
provide and pay the Company's portion of your medical insurance, except that
such severance payments made to you during this period will be reduced by all
1099 and W-2 income earned or received by you during such period, including
income earned or received from consulting services or temporary employment, and
the Company's payments for your medical insurance will terminate when you have
such coverage through any new employer before the end of the twelve month period
following your termination. The Company will reconcile such payments with you
quarterly, and any additional payments owed to you by the Company, and any
payments owed to the Company by you, will be paid respectively within two weeks
following such reconciliation period. The Company will not be obligated to
continue any such payments to you under this paragraph 3(e) in the event you
materially breach the terms under the Confidentiality Agreement (as defined
below). Notwithstanding any termination of your employment, you will continue to
be bound by the provisions of the Confidentiality Agreement.

         (f) For the purposes of this Section 3, "Cause" shall include (i) your
conviction of a felony, either in connection with the performance of your
obligations to the Company or otherwise, which adversely affects your ability to
perform such obligations or materially adversely affects the business
activities, reputation, goodwill or image of the Company, (ii) your willful
disloyalty, deliberate dishonesty, breach of fiduciary duty, (iii) your breach
of the terms of this Agreement, or your failure or refusal to carry out any
material tasks assigned to you by the Company in accordance with the terms
hereof, which breach or failure continues for a period of more than thirty (30)
days after your receipt of written notice thereof from the Company, (iv) the
commission by you of any act of fraud, embezzlement or deliberate disregard of a
significant rule or policy of the Company known to you or contained in a policy
and procedure manual provided to you which results in material loss, damage or
injury to the Company, or (v) the material breach by you of any of the
provisions of the Confidentiality Agreement substantially in the form of
Attachment A to this letter.

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MEMORY PHARMACEUTICALS CORP.
Gardiner F. H. Smith

         4. Benefits. You will be entitled as an employee of the Company to
receive such benefits as are generally provided its employees and executives and
for which you are eligible in accordance with Company policy as in effect from
time to time. The Company retains the right to change, add or cease any
particular benefit relating to its employees and executives generally. At this
time, the Company is offering a benefit program, consisting of medical, dental,
life and short/long term disability insurance, as well as a 401(k) retirement
plan and flexible spending plan. You will be eligible for eleven paid holidays,
four floating holidays and four (4) weeks paid vacation per year. You will
accrue additional vacation days in accordance with Company policy.

         5. Relocation Expenses. The Company will pay or reimburse you for all
reasonable out-of-pocket relocation and relocation-related expenses not to
exceed $100,000, including any Tax Payment (as defined below) and any Gross-up
Payment (as defined below), which may be billed directly to the Company or paid
by you and submitted for reimbursement, including, without limitation, the
following:

         (a) costs of services of moving companies (including packing,
transportation and relocation expenses, including the transportation of
automobiles);

         (b) costs associated with your search for a new residence (including,
without limitation, the costs of airfare, automobile rental, meals and hotel
accommodations for yourself and your immediate family);

         (c) commissions payable to brokers in connection with the sale of your
current residence;

         (d) costs attendant to the sale of your current residence and the
purchase of a new residence in the Northern New Jersey area (including, without
limitation, the costs of home inspections, survey, appraisal, title insurance,
transfer fees, attorneys' fees, accountants' fees, closing costs and down
payment on a new residence);

         (e) loan origination fees (points) related to the purchase of your new
residence in an amount of up to three percent (3%) of the loan amount (and the
Company will provide assistance to you relating to the selection of a mortgage
lender that will pre-qualify you for a mortgage loan to purchase your new
residence);

         (f) costs associated with commuting from your current residence to the
Company's offices (including, without limitation, the costs of airfare,
automobile rental, meals and hotel accommodations for you) for a period of up to
six months, subject to extension upon our mutual agreement;

         (g) automobile rental charges prior to establishment of a permanent
residence in Northern New Jersey;

         (h) rent and other expenses associated with temporary housing for
yourself and your immediate family for a period of up to six months (which may
include up to two months after the purchase and closing of title on your new
residence), subject to extension upon our mutual agreement; and

         (i) payment of any duplicate mortgage loan payments and house expenses
to preclude your paying for your current residence and your new residence
concurrently.

         (j) All such payments will be subject to the Company receiving
reasonably acceptable documentation evidencing the incurring of such cost,
expense or fee. In the event that it should be determined that any payment shall
be due by you for taxes of any kind or nature relating to amounts

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MEMORY PHARMACEUTICALS CORP.
Gardiner F. H. Smith

paid to you or on your behalf by the Company in connection with your relocation
as provided above ("Taxes"), the Company will deliver to you a payment equal to
the amount of such Taxes (the "Tax Payment") plus an additional payment in an
amount equal to any additional taxes payable by you applicable to your receipt
of the Tax Payment (the "Gross-Up Payment"). All such payments are fully
refundable to the Company if you leave the Company within twelve months of your
Start Date.

         6. Indemnification. The Company will indemnify you in connection with
any legal proceedings related to your actions on behalf of the Company,
including after your employment with the Company.

         7. Confidentiality. The Company considers the protection of its
confidential information and proprietary materials to be very important.
Therefore, as a condition of your employment, you and the Company will become
parties to a Confidentiality and Noncompetition Agreement substantially in the
form of Attachment A to this letter (the "Confidentiality Agreement").

         8. General.

         (a) This letter, together with the Confidentiality Agreement and the
Stock Option Agreement, will constitute our entire agreement as to your
employment by the Company and will supersede any prior agreements or
understandings, whether in writing or oral.

         (b) This letter shall be subject to our review of a satisfactory
medical examination.

         (c) This letter shall be governed by the law of the State of New
Jersey.

         You may accept this offer of employment and the terms thereof by
signing the enclosed additional copy of this letter and the Confidentiality
Agreement and the Stock Option Agreement, which execution will evidence your
agreement with the terms set forth herein and therein, and returning them to the
Company.

         This offer of employment will expire on December 28, 2001, unless
accepted by you prior to such date. We look forward to you joining our team, and
we believe that your skills will compliment those of our existing
management team, and that you will make a significant contribution to Memory's
growth. We look forward to your prompt response to this offer letter.

Sincerely,

/s/ Joanne Leonard
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Joanne Leonard
Senior Vice President
Chief Financial Officer
Memory Pharmaceuticals Corp.

ACCEPTED AND AGREED:

/s/ Gardiner F. H. Smith
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Date: December 18, 2001
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