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                                                                    Exhibit 10.8

                                 March 21, 1997

Barry N. Cheskin
43 West 61st Street
Apartment 19N
New York, NY  10023

Dear Barry:

     On behalf of Rita Medical Systems, Inc, (the "Company"), I am pleased to
offer you the position of President and Chief Executive Officer of the Company.
Speaking for myself, as well as the other members of the Company's Board of
Directors, 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 President and Chief Executive Officer of the
Company, working out of the Company's headquarters office in Mountain View,
California. As President and Chief Executive Officer, you will have overall
responsibility for the affairs of the Company. You will report directly to the
Chairman of the Company's Board of Directors and will be appointed to the Board
of Directors (the "Board") at the time you commence service as President and
Chief Executive Officer. The Company will use its best efforts to maintain you
on the Board throughout your period of employment with the Company as Chief
Executive Officer by taking all action necessary to nominate you for election to
the Board at each shareholders meeting held during your period of service as
Chief Executive Officer at which Board members are to be elected.

        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,
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whether or not for compensation, without the prior written consent of the Board,
and you will not directly or indirectly engaged 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, from serving on boards of charitable
organizations or otherwise rendering minor or insubstantial services for any
religious or charitable organizations of which you are a member 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 market.

     2. Start Date. Subject to fulfillment of any conditions imposed by this
letter agreement, you will commence this new position with the Company within
forty-five (45) days after execution of this agreement. The date you actually
commence employment with the Company will be designated as your Start Date.

     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 $16,666.67, which is
equivalent to $200,000 on an annualized basis. Your salary will be payable in
two equal payments per month pursuant to the Company's regular payroll policy
(or in the same manner as other officers of the Company).

     b. Bonus. You will be eligible to receive an incentive bonus of up to
thirty percent (30%) of your annual base salary, pro-rated for the portion of
the fiscal year ending December 31, 1997 which transpires from and after your
actual Start Date. Payment of the bonus will be at the discretion of the Board
and will be based on achievement of mutually agreeable objectives to be
determined by you and the Board within ninety (90) days after your Start Date.
You will also be eligible to earn incentive bonuses in future years of up to
thirty percent (30%) of your then current rate of annual base salary, again
based on achievement of mutually-agreed upon objectives and your continued
employment.

     c. Annual Review. Your base salary will be reviewed at the end of each
calendar year as part of the Company's normal salary review process.

     5. Stock Options.

     a. Initial Grant. The Board has authorized the following stock option grant
(the "Initial Option") under the Company's 1994 Incentive Stock Option Plan (the
"1994 Plan") which will become effectively immediately upon your Start Date. The
option will provide you with the right to purchase that number of shares of the
Company's Common Stock ("Shares") which represent seven percent (7%) of the
Company's capital stock outstanding on your Start Date, calculated on a fully
diluted basis, taking into account all outstanding convertible
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securities, warrants, options and similar instruments and the number of shares
of Common Stock which remain available for future option grant or issuance under
the 1994 Plan. The option will have an exercise price equal to the fair market
value per share of Common Stock on your Start Date (currently the fair market
value per share is $0.30). The option will be immediately exercisable for fifty
percent (50%) of the total option shares as fully-vested shares and will become
exercisable for the balance of those shares in a series of twenty-four (24)
successive equal monthly installments upon your completion of each month of
service with the Company, whether as an employee, non-employee Board member or
independent consultant, over the twenty-four (24)-month period measured from the
second anniversary of your Start Date. 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 Plan and the Stock Option Agreement between you and
the Company.

     b. Anti-Dilution Protection. In the event the Company raises additional
capital through one or more equity issuances effected after your Start Date
other than through the exercise or conversion of securities taken into account
in calculating your initial seven percent (7%) interest or through an initial
public offering of the Company's common stock, your seven percent (7%) equity
interest shall be protected through the first $7,500,000 of such equity capital,
calculated on an aggregate basis. In no event shall your seven percent (7%)
equity interest be diluted below five percent (5%). In addition, your initial
seven percent (7%) equity interest will be protected against any dilution
attributable to any increase in the number of shares of the Company's capital
stock authorized for issuance under the 1994 Plan (or any successor or
additional employee stock option plan) effected prior to the initial public
offering of the Company's common stock. Your anti-dilution protection will be
provided through a series of additional option grants ("Anti-Dilution Options")
made to you under the 1994 Plan at each time a dilutive event is consummated
after your Start Date. Each Anti-Dilution Option will have an exercise price per
share equal to the fair market value of the Common Stock at the time a dilutive
event is consummated and will become exercisable for the option shares in
accordance with the same vesting schedule in effect for your Initial Option
(i.e., immediate vesting in fifty percent (50%) of the option shares and vesting
in the balance of the shares over the twenty-four (24) month period measured
from the second anniversary of your Start Date). No such anti-dilution
protection will be provided you in connection with the initial public offering
of the Common Stock or any subsequent issuance of securities effected
thereafter.

     c. Change in Control Protection. In the event (i) the Company sells all or
substantially all of its assets, (ii) the Company merges with another entity
pursuant to which shareholders of the Company immediately prior to the merger
own less than fifty percent (50%) of the voting securities of the surviving
entity or (iii) the Company's securities holders sell securities possessing
fifty percent (50%) or more of the total combined voting power of the Company's
outstanding securities, then immediately prior to the closing of such
sale/merger transaction, your Initial Option and each Anti-Dilution Option will
become exercisable for seventy-five percent (75%) of your then invested option
shares. The balance of the shares subject to each such option will vest, at the
rate of 2.0833% of the total number of shares for which that option was
originally granted, upon your completion of each additional month of service
with the Company or the successor entity following the sale/merger transaction.
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     d. Tax Gross-Up. Should the accelerated vesting of your option shares,
either at the time of the sale/merger transaction pursuant to paragraph 5.c or
your subsequent termination of employment pursuant to paragraph 8, trigger an
excess parachute payment under Section 280(G) of the Internal Revenue Code in
connection with a sale/merger transaction consummated before any of the
Company's securities have become tradable on an established securities market,
then the Company shall provide you with a full tax-gross-up with respect to your
parachute tax liability under Section 4999 of the Internal Revenue Code.

     e. Company Repurchase Rights. Should any of the following events
("Repurchase Event") occur during the first twenty-four (24) months of your
employment: (i) you voluntarily leave the Company's service other than for Good
Reason or (ii) your employment is terminated by the Company for Misconduct, then
the Company will have the following repurchase rights with respect to up to
fifty percent (50%) of the shares purchased or purchasable under your paragraph
5.a and 5.b stock options:

          - The number of shares which the Company may repurchase will be equal
     to fifty percent (50%) of the total number of shares subject to all your
     paragraph 5.a and 5.b options if the Repurchase Event occurs before you
     have completed six (6) months of service. The number of the shares
     repurchasable by the Company will decrease to thirty seventy and one-half
     percent (37.5%) of that total upon your completion of six (6) months of
     service and will decline by an additional 2.0833% of your total option
     shares upon your completion of each of the next eighteen (18) months of
     service so that the Company's repurchase rights will terminate as to all
     your option shares upon your completion of twenty-four (24) months of
     service measured from your Start Date.

          - The amount payable per repurchased share by the Company will be
     equal to the fair market value per share of the Company's common stock at
     the time of the repurchase (as determined in good faith by the Board) in
     the event of a clause (i) Repurchase Event and will be equal to the option
     exercise price paid per share in the event of a clause (ii) Repurchase
     Event.

          - The Company's repurchase rights under this paragraph 5.e will
     immediately terminate upon a sale/merger transaction under paragraph 5.c
     which triggers the accelerated vesting of your option shares.

     f. Subsequent Option Grants. Subject to the discretion for the Board, 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 shall determine as of the date of any such grant.

     6. Benefits.

     a. Insurance Benefits. The Company will provide you and your eligible
dependents with standard medical and dental insurance benefits. You will also be
eligible to
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participate in al other benefit programs available to the Company's executives,
including group-term life insurance coverage and the long-term disability income
plan, to the extent you satisfy the applicable eligibility requirements. In
addition, the Company currently indemnifies all officers and directors to the
maximum extent permitted by law, and you will be requested to enter into the
Company's standard form of Indemnification Agreement (in the form attached as
Exhibit A) giving you such protection. Pursuant to the Indemnification
Agreement, the Company will agree to advance any expenses for which
indemnification is available to the extent allowed by applicable law.

     b. Vacation. You will be entitled to four (4) weeks paid vacation per year,
pro-rated for the remainder of this calendar year.

     c. Auto Allowance. The Company will pay you a monthly automobile allowance
of Seven Hundred Fifty Dollars ($750.00).

     d. Relocation Expenses. In connection with your relocation from New York to
Northern California, the Company will, to the extent required to avoid
out-of-pocket cost to you, reimburse you for up to six (6) months of rental
payments on your New York apartment ($2,500 per month for a maximum of six (6)
months). In connection with your purchase of a residence in Northern California,
the Company will also provide you with a housing subsidy of Thirty-Five Hundred
Dollars ($3,500) per month for the first twenty-four (24) months of your
employment with the Company. In addition, the Company will reimburse you for the
following expense ("Relocation Expenses"):

          - all reasonable relocation expenses, including house-hunting trips,
     moving of household goods and automobile and other reasonable out-or-pocket
     expenses, including expenses incurred in any second move you may have to
     make from any apartment or other temporary lodgings you rent upon your
     relocation to your new permanent residence (but excluding home decorating
     expenses, differences in mortgage rates, differences in costs of comparable
     housing, etc.), closing costs and fees including up to 1.5 mortgage points,
     up to a maximum aggregate reimbursable amount of Thirty Five Thousand
     Dollars ($35,000);

          - reasonable temporary living expenses not to exceed three (3) months,
     and

          - The cost of up to four (4) trips in the aggregate between New York
     and San Francisco by either you or your spouse in the event your spouse is
     unable to relocate immediately with you.

     All amounts received by you for relocation expense reimbursement under this
Paragraph 6.d will be reported as taxable income to you in the year received as
required by applicable tax law. However, the Company will reimburse you on a
"gross-up" basis for the income tax effect of your non-deductible reimbursed
Relocation Expenses so that you will not incur any out-of-pocket cost with
respect to those latter expenses.
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     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.

     a. Severance Benefits. In the event (i) your employment is terminated by
the Company or its successor for any reason other than Misconduct or (ii) you
resign for Good Reason, you will be entitled to the following severance
benefits:

          - You will receive continuation of your base salary for up to twelve
     (12) months following the date of your termination or resignation (the
     "Severance Period"). 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, but not limited to, consulting or other
     contract work.

          During the Severance Period the Company shall pay for your purchase of
     continued health care coverage for you and your eligible dependents upon
     your election to receive such continued health benefits under COBRA; any
     additional COBRA coverage to which you and your dependents may be entitled
     following the expiration of the Severance Period will be at your own cost.

          The shares subject to each of your outstanding stock options will
     immediately vest in full. If the Company has not yet effected the initial
     public offering of its Common Stock, then you will have until the earlier
     of (i) the end of the one (1)-year period following your termination date
     or (ii) the expiration of the ten (10)-year option term in which to
     exercise those options.

     b. Definitions. For purposes of this letter agreement, the following
definitions will be in effect:

          You will be deemed to have resigned for Good Reason if such
     resignation occurs by reason of (i) a change in your position with the
     Company which materially reduces your duties or level of responsibility,
     (B) a reduction in the level of your base compensation by more than fifteen
     percent (15%) or (C) a relocation of your place of employment by more than
     fifty (50) miles.

          Your employment will be deemed to have been terminated for Misconduct
     if such termination occurs by reason of your commission of any act of
     fraud, embezzlement or dishonesty, your unauthorized user or disclosure
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     by you of confidential information or trade secrets of the Company, or any
     other gross negligence or intentional misconduct on your part which
     adversely affects or is likely to adversely affect the business or affairs
     of the Company in a material manner.

     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 letter 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 and may disclose such terms to the extent required by law.

     10. Governing Law/Successors and Assigns. The provisions of this letter
agreement shall, in all respects, be governed by the laws of the State of
California applicable to agreements executed and to be wholly performed within
the State of California. The provisions of this letter agreement shall inure to
the benefit of, and shall be binding upon, the Company and its successors and
assigns, and you, the personal representative of your estate and your heirs and
legatees. Should th Board or the Company's shareholders authorize any
reorganization of the Company prior to your actual Start Date, then the Company
will structure such reorganization so that the successor entity will assume all
obligations and commitments of the Company hereunder, and you will accordingly
be allowed to commence your employment with such successor entity in accordance
with all the terms and provisions of this letter agreement.

     11. 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 other than any severance benefits to which you are entitled under
Paragraph 8 of this letter agreement.

     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 singed and dated copy of the Confidentiality Agreement.

     In the event it is determined by the Board, upon consultation with Company
management and the Company's independent auditors, that the enforcement of
paragraph 5.c of this letter agreement, which allows for the partial
acceleration of vesting of stock options upon the effective date of a sale or
merger of the Company, would preclude accounting for any proposed business
combination of the Company as a pooling of interests, and the Board otherwise
desires to approve such a proposed business transaction which requires as a
condition to the closing of such transaction that it be accounted for as a
pooling interests, then such paragraph 5.c of this letter agreement shall be
null and void. For purposes of this paragraph, the Board's determination shall
require the unanimous approval of the non-employee Board members.

     This letter, together with the Confidentiality Agreement and
Indemnification Agreement, set forth the terms of your employment with the
Company and supersede any prior
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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 to you will expire and be of no further force or effect at the
close of business on March 24, 1997, unless you accept this offer prior to that
time.

                                               Very truly yours,

                                               RITA MEDICAL SYSTEMS, INC.



                                               By: /s/ J. Thomas McMurray
                                                   -----------------------------
                                                   J. Thomas McMurray
                                                   Title:  Chairman of the Board

ACCEPTED AND AGREED:

BARRY N. CHESKIN

/s/ Barry N. Cheskin
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Signature

March 21, 1997
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Date

Enclosure: Confidential Information and Invention Assignment Agreement