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                                                                   Exhibit 10.10



February 11, 2000

David L. Martin
20 Highcrest Lane
So. San Francisco, CA.  94080

Dear Dave:

     On behalf of RITA Medical Systems, Inc. (the "Company"), I am pleased to
offer you the position of Vice President, Global Sales. Speaking for myself, as
well as the other members of the Company's management team, we are all very
impressed with your credentials and we look forward to your future success in
this position.

     The terms of your new position with the Company are as set forth below:
     1. Position.

     a. You will become the Vice President, Global Sales, working out of the
Company's office in Mountain View, California. You will report to the President
and CEO.

     b. You agree to the best of your ability and experience that you will at
all times loyally and conscientiously perform all of the duties and obligations
required of and from you pursuant to the express and implicit terms hereof, and
to the reasonable satisfaction of the Company. During the term of your
employment, you further agree that you will devote all of your business time and
attention to the business of the Company, the Company will be entitled to all of
the benefits and profits arising from or incident to all such work services and
advice, you will not render commercial or professional services of any nature to
any person or organization, whether or not for compensation, without the prior
written consent of the Company's Board of Directors, and you will not directly
or indirectly engage or participate in any business that is competitive in any
manner with the business of the Company. Nothing in this letter agreement will
prevent you from accepting speaking or presentation engagements in exchange for
honoraria or from serving on boards of charitable organizations, or from owning
no more than one percent (1%) of the outstanding equity securities of a
corporation whose stock is listed on a national stock exchange.

     2. Start Date. Subject to fulfillment of any conditions imposed by this
letter agreement, you will commence this new position with the Company on or
before March 15, 2000.
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     3. Proof of Right to Work. For purposes of federal immigration law, you
will be required to provide to the Company documentary evidence of your identity
and eligibility for employment in the United States. Such documentation must be
provided to us within three (3) business days of your date of hire, or our
employment relationship with you may be terminated.

     4. Compensation.

     a. Base Salary. You will be paid a monthly salary of $13,750.00 which is
equivalent to $165,000 on an annualized basis. Your salary will be payable in
two equal payments on the 15th and the last day of the month.

     b. Sales Bonus. You will receive a sales bonus based on achieving the
Company's sales targets. These targets and your bonus will be mutually agreed
upon on an annual basis. For the calendar year 2000, you will receive a
commission of 0.5% of sales up to $9.5 million in revenue and 2.0% of sales
above $9.5 million in revenue. Commissions will be paid monthly in the first
paycheck following the end of the month in which the commission is earned. In
addition, you will be paid an annual bonus of $25,000 upon achieving the
Company's stretch sales goals.

     c. One-Time Bonus. You will receive a one-time cash bonus of $50,000,
payable in two equal installments at the completion of 3 months and 12 months of
employment.

     5. Stock Options.

     a. Initial Grant. In connection with the commencement of your employment,
the Company will recommend that the Board of Directors grant you an option to
purchase 300,000 shares of the Company's Common Stock ("Shares") with an
exercise price equal to the fair market value on the date of the grant. These
option shares will vest at the rate of 1/8 of the total after the first six
months of employment and then 1/48 of the total per month, such that the options
will become fully vested at the end of four years. Vesting will, of course,
depend on your continued employment with the Company. The option will be an
incentive stock option to the maximum extent allowed by the tax code and will be
subject to the terms of the Company's 1994 Incentive Stock Option Plan and the
Stock Option Agreement between you and the Company. This option is subject to
the approval of the Company's Board of Directors.

     b. Subsequent Option Grants. Subject to the discretion of the Company's
Board of Directors, you may be eligible to receive additional grants of stock
options or purchase rights from time to time in the future, on such terms and
subject to such conditions as the Board of Directors shall determine as of the
date of any such grant. In addition, you will participate in any annual employee
stock bonus plan for which you are eligible.

     6. Benefits.

     a. Insurance Benefits. The Company will provide you with medical, dental
and long-term disability insurance benefits.
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     b. Vacation. You will be entitled to 3 weeks paid vacation per year,
pro-rated for the remainder of this calendar year. Vacation accrues as follows:
five (5) hours accrue per pay period from your date of hire. During the first
six months, no vacation may be taken unless a special exception has been
granted.

     c. 401K Retirement Plan. You will be eligible to participate in the
Company's employee-contribution 401K Retirement Plan beginning on the first
January 1 or July 1 following one month of employment.

     7. Salary Continuation. Following the six-month anniversary of your
employment with the Company, if you are involuntarily terminated other than for
cause, you will be paid continuation of your base salary for a period of up to
twelve months or until you secure other employment, whichever is earlier. Salary
continuation will be paid on regular Company paydays.

     8. Confidential Information and Invention Assignment Agreement. Your
acceptance of this offer and commencement of employment with the Company is
contingent upon the execution, and delivery to an officer of the Company, of the
Company's Confidential Information and Invention Assignment Agreement, a copy of
which is enclosed for your review and execution (the "Confidentiality
Agreement"), prior to or on your Start Date.

     9. Confidentiality of Terms. You agree to follow the Company's strict
policy that employees must not disclose, either directly or indirectly, any
information, including any of the terms of this agreement, regarding
compensation, or stock purchase or option allocations to any person, including
other employees of the Company; provided, however, that you may discuss such
terms with members of your immediate family and any legal, tax or accounting
specialists who provide you with individual legal, tax or accounting advice.

     10. At-Will Employment. Your employment with the Company will be on an "at
will" basis, meaning that either you or the Company may terminate your
employment at any time for any reason or no reason, without further obligation
or liability.

     We are all delighted to be able to extend you this offer and look forward
to working with you. To indicate your acceptance of the Company's offer, please
sign and date this letter in the space provided below and return it to me, along
with a signed and dated copy of the Confidentiality Agreement. This letter,
together with the Confidentiality Agreement, set forth the terms of your
employment with the Company and supersede any prior representations or
agreements, whether written or oral. This letter may not be modified or amended
except by a written agreement, signed by the Company and by you. This offer will
expire unless signed by you by February 14, 2000.
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                            (SIGNATURE PAGE FOLLOWS)
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                                                      Very truly yours,

                                                      RITA MEDICAL SYSTEMS, INC.

                                                      By: /s/ Barry Cheskin
                                                          ---------------------

                                                      Title: President & CEO


ACCEPTED AND AGREED:

DAVID L. MARTIN

/s/ David Martin
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Signature

February 11, 2000
Date

Enclosure: Confidential Information and Invention Assignment Agreement