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                                                                    Exhibit 10.9


May 26, 1998

Ronald Steckel
1353 Abbott Avenue
Campbell, CA 95008

Dear Ron:

     On behalf of RITA Medical Systems, Inc. (the "Company"), I am pleased to
offer you the position of Vice President, Operations. 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, Operations working out of the
Company's office in Mountain View, California. As Vice President, Operations,
you will have overall responsibility for matters relating to the manufacturing
and manufacturing engineering areas in the Company. You will report to the
Company's President and Chief Executive Officer.

     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 June
29, 1998. You have agreed to be available on a limited basis prior to that time,
consistent with your current commitments, to aid in the transition.
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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 $12,500.00 which is
equivalent to $150,000 on an annualized basis. Your salary will be payable in
two equal payments per month pursuant to the Company's regular payroll policy.

     b. One-Time Bonus. You will receive a one-time cash bonus of $30,000
payable as follows: $10,000 within 30 days of your start date; then $5,000 at
each quarterly anniversary of your start date, ending at the completion of your
first year of employment.

     c. Bonus. You will be eligible to participate in the Company management
bonus program if and when such a program is developed and approved by the Board
of Directors.

     d. Annual Review. Your base salary will be reviewed as part of the
Company's normal salary review process.

     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 a number of shares of the Company's Common Stock ("Shares") which will
represent 1% of the fully diluted capitalization of the Company immediately upon
the completion of the Series E financing, with an exercise price equal to the
fair market value on the date of the grant. The grant amount is estimated to be
136,500 shares, based on the projected closing capitalization of the Series E
round, though this amount may be adjusted to exactly reflect the 1% figure.
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 would 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.
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     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.

     6. Benefits.

     a. Insurance Benefits. The Company will provide you with standard medical
and dental insurance benefits.

     b. Vacation. You will be entitled to 3 weeks paid vacation per year,
pro-rated for the remainder of this calendar year. Vacation accrues according to
Company policy as described in the employee handbook. At this time the following
schedule applies: 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.

     7. 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.

     8. Severance Agreement. If your employment is terminated by the Company or
its successor for any reason other than cause, as determined by the Company's
Board of Directors, you will be entitled to receive continuation of your base
salary payable in two equal payments per month for up to six (6) months
following the date of termination of your employment (the "Severance Period").
This salary continuation is conditioned on your confirmation, to the Company's
satisfaction, that you are actively seeking full-time employment. In the event
you commence full-time employment during the Severance period, the Company's
obligation to pay any severance shall cease at the time of such employment. For
purposes of this paragraph, "full-time employment" shall be defined as at least
35 hours per week of compensated labor, including consulting or other contract
work.

     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 salary,
bonuses, 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.
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     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 May 29, 1998.

                                                     Very truly yours,

                                                     RITA MEDICAL SYSTEMS, INC.

                                                     By: /s/ Barry N. Cheskin
                                                        ------------------------

                                                     Title: President and C.E.O.

ACCEPTED AND AGREED:

RONALD STECKEL


/s/ Ronald Steckel
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Signature

May 26, 1998

Date

Enclosure: Confidential Information and Invention Assignment Agreement