SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                  ___________

                                   FORM 8-A

               FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                   PURSUANT TO SECTION 12 (b) OR (g) OF THE
                        SECURITIES EXCHANGE ACT OF 1934



                          RITA MEDICAL SYSTEMS, INC.
            (Exact Name of Registrant as Specified in Its Charter)



                Delaware                              94-3199149
 ---------------------------------------            --------------
(State of Incorporation or Organization)            (IRS Employer
                                                 Identification No.)


967 North Shoreline Blvd., Mountain View, CA            94043
--------------------------------------------        --------------
 (Address of Principal Executive Offices)             (Zip Code)


Securities to be registered pursuant to Section 12(b) of the Act:


     Title of each class                 Name of each exchange on which
     to be so registered                 each class is to be registered
     -------------------                 ------------------------------

         None                                   None

       Securities to be registered pursuant to Section 12(g) of the Act:

                        Preferred Share Purchase Rights
                        -------------------------------
                               (Title of Class)


Item 1.  Description of Registrant's Securities to be Registered.
         -------------------------------------------------------

     Effective as of July 31, 2001, the Board of Directors of RITA Medical
Systems, Inc. (the "Company") declared a dividend of one preferred share
                    -------
purchase right (a "Right") for each outstanding share of Common Stock, $0.001
                   -----
par value (the "Common Shares"), of the Company. The dividend is payable on
                -------------
August 15, 2001 (the "Record Date") to stockholders of record as of the close of
                      -----------
business on that date.  Each Right entitles the registered holder to purchase
from the Company one one-thousandth of a share of Series A Participating
Preferred Stock, $0.001 par value, of the Company (the "Preferred Shares"),
                                                        ----------------
subject to adjustment, at a price of $25.00 per one-thousandth of a preferred
share, subject to adjustment (the "Purchase Price").  The description and terms
                                   --------------
of the Rights are set forth in a Preferred Shares Rights Agreement (the "Rights
                                                                         ------
Agreement") dated as of July 31, 2001 between the Company and U.S. Stock
---------
Transfer Corporation, as Rights Agent (the "Rights Agent").
                                            ------------

     The following is a general description only and is subject to the detailed
terms and conditions of the Rights Agreement. A copy of the Rights Agreement,
including the Certificate of Designation, the form of Rights Certificate and the
Summary of Rights to be provided to stockholders of the Company, is attached as
Exhibit 1 to this Registration Statement and is incorporated herein by
---------
reference.

Rights Evidenced by Common Share Certificates
---------------------------------------------

     The Rights will not be exercisable until the Distribution Date (defined
below).  Accordingly, Common Share certificates outstanding on the Record Date
will evidence the Rights related thereto, and Common Share certificates issued
after the Record Date will contain a notation incorporating the Rights Agreement
by reference.  Until the Distribution Date (or earlier redemption, exchange or
expiration of the Rights), the surrender or transfer of any certificates for
Common Shares, even without notation or a copy of the Summary of Rights being
attached thereto, will also constitute the transfer of the Rights associated
with the Common Shares represented by such certificate.

                                      -2-


Distribution Date
-----------------

     The Rights will separate from the Common Shares, certificates for the
rights ("Rights Certificates") will be issued and the Rights will become
         -------------------
exercisable upon the earlier of:  (i) the close of business on the tenth day (or
such later date as may be determined by a majority of the Board of Directors)
following a public announcement that a person or group of affiliated or
associated persons has acquired, or obtained the right to acquire, beneficial
ownership of 15% or more of the outstanding Common Shares (an "Acquiring
                                                               ---------
Person") or (ii) the close of business on the tenth day (or such later date as
------
may be determined by a majority of the Board of Directors) following the
commencement of a tender offer or exchange offer, the consummation of which
would result in the beneficial ownership by a person or group of 15% or more of
the outstanding Common Shares.  The earlier of such dates is referred to as the
"Distribution Date."
 -----------------

Issuance of Rights Certificates, Expiration of Rights
-----------------------------------------------------

     As soon as practicable following the Distribution Date, separate Rights
Certificates will be mailed to holders of record of the Common Shares as of the
close of business on the Distribution Date and such separate Rights Certificates
alone will evidence the Rights from and after the Distribution Date.  Unless
otherwise determined by the Board of Directors, all Common Shares issued prior
to the Distribution Date will be issued with Rights.  Common Shares issued after
the Distribution Date may be issued with Rights if such shares are issued (i)
upon the exercise, conversion or exchange of securities issued after adoption of
the Rights Agreement or (ii) pursuant to the exercise of stock options or under
any employee benefit plan or arrangement.  Except as otherwise determined by the
Board of Directors, no other Common Shares issued after the Distribution Date
will be issued with Rights.  In addition, no Common Shares issued after the
Distribution Date will be issued with Rights if such issuance would result in
(or create a significant risk) (i) of material adverse tax consequences to the
Company or the person to whom such Rights Certificate would be issued or (ii)
that such options or plans would not qualify for otherwise available special tax
treatment.  The Rights will expire on July 31, 2011 (the "Final Expiration
                                                          ----------------
Date"), unless the Final Expiration Date is extended or unless the Rights are
----
earlier

                                      -3-


redeemed or exchanged by the Company or expire upon consummation of certain
mergers, consolidations or sales of assets, as described below.

Initial Exercise of the Rights
-------------------------------

     Following the Distribution Date, and until the occurrence of one of the
subsequent events described below, holders of the Rights will be entitled to
receive, upon exercise and the payment of $25.00 (the "Purchase Price") per
                                                       --------------
Right, one one-thousandth of a Preferred Share.

Exchange Provision
-----------------

     At any time after an Acquiring Person has become such and prior to the
Acquiring Person beneficially owning 50% or more of the outstanding Common
Shares, the Board of Directors may exchange the Rights (other than Rights owned
by the Acquiring Person or its affiliates), in whole or in part, at an exchange
ratio of one Common Share per Right (subject to adjustment).

Right to Buy Common Shares at Half Price
----------------------------------------

     Unless the Rights are earlier redeemed or exchanged, in the event that an
Acquiring Person becomes such, other than pursuant to a tender offer which is
made for all of the outstanding Common Shares and approved by a majority of the
Board of Directors after determining that the offer is both adequate and
otherwise in the best interests of the Company and its stockholders (a
"Permitted Offer"), then proper provision will be made so that each holder of a
 ---------------
Right which has not theretofore been exercised (other than Rights beneficially
owned by the Acquiring Person, which will thereafter be void) will thereafter
have the right to receive, upon exercise of a Right, a number of Common Shares
having a then current value equal to two times the Purchase Price.  In the event
that the Company does not have a sufficient number of Common Shares available,
or the Board of Directors decides that such action is necessary or appropriate
and not contrary to the interests of Rights holders, the Company may, among
other things, instead substitute cash, assets or other securities for the Common
Shares into which the Rights would have otherwise been exercisable.

                                      -4-


Right to Buy Acquiring Company Stock at Half Price
--------------------------------------------------

     Similarly, unless the Rights are earlier redeemed or exchanged, in the
event that, after the Shares Acquisition Date (as defined below), (i) the
Company consolidates with or merges into another entity, (ii) another entity
consolidates with or merges into the Company or (iii) the Company sells or
otherwise transfers 50% or more of its consolidated assets or earning power,
proper provision must be made so that each holder of a Right which has not
theretofore been exercised (other than Rights beneficially owned by the
Acquiring Person, which will thereafter be void) will thereafter have the right
to receive, upon exercise, a number of shares of common stock of the acquiring
company having a then current value equal to two times the Purchase Price
(unless the transaction satisfies certain conditions and is consummated with a
person who acquired shares pursuant to a Permitted Offer, in which case the
Rights will expire).

Adjustments to Prevent Dilution
-------------------------------

     The Purchase Price payable, the number of Rights and the number of
Preferred Shares, Common Shares or other securities or property issuable upon
exercise of the Rights are subject to adjustment from time to time to prevent
dilution as set forth in the Rights Agreement.  With certain exceptions, no
adjustment in the Purchase Price will be required until cumulative adjustments
require an adjustment of at least 1% in such Purchase Price.

Rights and Preferences of the Preferred Shares
----------------------------------------------

     Preferred Shares purchasable upon exercise of the Rights will not be
redeemable.  Each Preferred Share will be entitled to an aggregate dividend of
1,000 times the dividend declared per Common Share.  In the event of
liquidation, the holders of the Preferred Shares will be entitled to a
preferential liquidation payment equal to accrued but unpaid dividends plus the
greater of $1,000 per share or 1,000 times the aggregate per share amount to be
distributed to the holders of Common Shares.  Each Preferred Share will have
1,000 votes, voting together with the holders of Common Shares, except as
required by law or the Certificate of Determination of Rights, Preferences and
Privileges of Series A Participating Preferred Stock.  In the event of any
merger,

                                      -5-


consolidation or other transaction in which Common Shares are changed or
exchanged, each Preferred Share will be entitled to receive 1,000 times the
amount received per Common Share.  These rights are protected by customary anti-
dilution provisions.  Because of the nature of the dividend, liquidation and
voting rights of the Preferred Shares, the value of the one one-thousandth
interest in a Preferred Share purchasable upon exercise of each Right should
approximate the value of one Common Share.

Redemption
----------

     At any time prior to the close of business on the earlier of (i) the tenth
day following the date (the "Shares Acquisition Date") of public announcement
                             -----------------------
that an Acquiring Person has become such or such later date as may be determined
by a majority of the Board of Directors and publicly announced by the Company or
(ii) the Final Expiration Date of the Rights, the Company may redeem the Rights
in whole, but not in part, at a price of $0.01 per Right ("Redemption Price").
                                                           ----------------

No Stockholders' Rights Prior to Exercise
-----------------------------------------

     Until a Right is exercised, the holder thereof, as such, will have no
rights as a stockholder of the Company (other than any rights resulting from
such holder's ownership of Common Shares), including, without limitation, the
right to vote or to receive dividends.

Amendment of Rights Agreement
-----------------------------

     The provisions of the Rights Agreement may be supplemented or amended by
the Board of Directors in any manner prior to the Distribution Date without the
approval of Rights holders.  After the Distribution Date, the provisions of the
Rights Agreement may be supplemented or amended by the Board of Directors in
order to (i) cure any ambiguity, defect or inconsistency, (ii) to make changes
which are deemed necessary or advisable and do not adversely affect the
interests of holders of Rights (excluding the interests of any Acquiring
Person), or (iii) to shorten or lengthen any time period under the Rights
Agreement; provided, however, that no amendment to lengthen (A) the time period
governing redemption shall be made at such time as the Rights

                                      -6-


are not redeemable, or (B) any other period unless for the purpose of
protecting, enhancing or clarifying the rights of, and/or benefits to, the
holders of Rights.

Certain Anti-takeover Effects
-----------------------------

     The Rights approved by the Board of Directors are designed to protect and
maximize the value of the outstanding equity interests in the Company in the
event of an unsolicited attempt by an acquiror to take over the Company, in a
manner or on terms not approved by the Board of Directors.  Takeover attempts
frequently include coercive tactics to deprive a corporation's Board of
Directors and its stockholders of any real opportunity to determine the destiny
of the corporation.  The Rights have been declared by the Board of Directors in
order to deter such tactics, including a gradual accumulation of shares in the
open market of a 15% or greater position to be followed by a merger or a partial
or two-tier tender offer that does not treat all stockholders equally.  These
tactics unfairly pressure stockholders, squeeze them out of their investment
without giving them any real choice and deprive them of the full value of their
shares.

     The Rights are not intended to prevent a takeover of the Company and will
not do so.  The Rights are not exercisable in the event of a Permitted Offer, as
described above.  The Rights may be redeemed by the Company at $0.01 per Right
within ten days (or such later date as may be determined by a majority of the
Board of Directors) after the accumulation of 15% or more of the Company's
outstanding Common Shares by a single acquiror or group.  Accordingly, the
Rights should not preclude any merger or business combination approved by the
Board of Directors.  Issuance of the Rights does not in any way weaken the
financial strength of the Company or interfere with its business plans. The
issuance of the Rights has no immediate dilutive effect, will not affect
reported earnings per share, should not be taxable to the Company or to its
stockholders and will not change the way in which the Company's shares are
presently traded.  The Company's Board of Directors believes that the Rights
represent a sound and reasonable means of addressing the complex issues of
corporate policy created by the current takeover environment.  However, the
Rights may have the effect of rendering more difficult or discouraging an
acquisition of the Company deemed undesirable by the Board of Directors.  The

                                      -7-


Rights may cause substantial dilution to a person or group that attempts to
acquire the Company on terms or in a manner not approved by the Board of
Directors, except pursuant to an offer conditioned upon the negation, purchase
or redemption of the Rights.

Item 2.   Exhibits.
-------   --------

          1.  Preferred Shares Rights Agreement, dated as of July 31, 2001,
              between RITA Medical Systems, Inc. and U.S. Stock Transfer
              Corporation, including the Certificate of Designation, the form of
              Rights Certificate and the Summary of Rights attached thereto as
              Exhibits A, B and C, respectively.

                                      -8-



                                   SIGNATURE

     Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereto duly authorized.

                                    RITA MEDICAL SYSTEMS, INC.


Date:  August 7, 2001               By  /s/ Barry Cheskin
                                        -----------------
                                        Barry Cheskin
                                        President and Chief Executive Officer


                          RITA MEDICAL SYSTEMS, INC.

                      REGISTRATION STATEMENT ON FORM 8-A

                                 EXHIBIT INDEX
                                 -------------


    Exhibit
      No.                              Exhibit
----------------    ----------------------------------------------

       1            Preferred Shares Rights Agreement, dated as of
                    July 31, 2001, between RITA Medical Systems,
                    Inc. and U.S. Stock Transfer Corporation,
                    including the Certificate of Designation, the
                    form of Rights Certificate and the Summary of
                    Rights attached thereto as Exhibits A, B and
                    C, respectively.