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                                                                  EXHIBIT 10.21

                          CARDIAC PATHWAYS CORPORATION

                              CONSULTING AGREEMENT


         This Agreement (the "Agreement") is made by and between Cardiac
Pathways Corporation (the "Company") and Earle Canty (the "Consultant") as of
September 1, 1998.

         1. SERVICES. The Consultant shall provide to the Company the services
set forth in Paragraph 1 of Exhibit A in accordance with the terms and
conditions contained in this Agreement. The manner and means by which Consultant
chooses to complete the Projects are in consultant's sole discretion and
control. Consultant agrees to exercise the highest degree of professionalism,
and utilize its expertise and creative talents in achieving such Projects. The
Company will make its facilities, equipment and personnel available to
Consultant when necessary. Consultant shall perform the services necessary to
achieve the Projects in a timely manner consistent with industry standards at a
location, place and time which the Consultant deems appropriate.

         2. TERM. Unless terminated in accordance with the provisions of
Paragraph 7 hereof, the services provided by the Consultant to the Company shall
be performed during the period set forth in Paragraph 2 of Exhibit A or up to
completion of the project as described in Paragraph 2 of Exhibit A. The
Consultant shall coordinate his work efforts and report his progress regularly
to the individual set forth in Paragraph 3 of Exhibit A.

         3. PAYMENT FOR SERVICE RENDERED. For providing the consulting services
as defined herein, the Company shall deliver to the Consultant the consideration
described in Paragraph 4 of Exhibit A. The Company shall reimburse the
Consultant for all reasonable expenses provided the Company has approved the
expenses in advance and in writing.

         4. NATURE OF RELATIONSHIP. The Consultant is an independent contractor.
The Consultant will not act as an agent nor shall be deemed and employee of the
Company for the purposes of any employee benefit program, income tax
withholding, FICA taxes, unemployment benefits, or otherwise. As an independent
contractor, the Company will not withhold or make payments for state of federal
income tax or social security; make unemployment insurance or disability
insurance contributions; or obtain workers compensation insurance on
Consultant's behalf. The Company will issue Consultant a 1099 form with respect
to Consultant's consulting fees. Consultant agrees to accept exclusive liability
for complying with all applicable state and federal laws governing self employed
individuals, including obligations such as payment of quarterly taxes, social
security, disability and other



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contributions based on the fees paid to Consultant, its agents or employees
under this Agreement. Consultant hereby indemnifies and defends the Company
against any and all such taxes or contributions. Consultant will not receive any
employee benefits such as paid holidays, vacations, sick leave or other such
paid time off, or participate in company-sponsored health insurance or other
employee benefit plans. The Consultant shall not enter into any agreement or
incur obligations on the Company's behalf, or commit the Company in any manner
without the Company's prior written notice.

         5. CONFIDENTIALITY.

         (a) The Consultant agrees that he shall not use (except for the
Company's benefit) or divulge to anyone either during the term of this Agreement
or thereafter any of the Company's trade secrets or other proprietary data or
information of any kind whatsoever acquired by the Consultant. The Consultant
further agrees that upon completion or termination of this Agreement, he will
turn over to the Company any notebook, data, information or other material
acquired or compiled by the Consultant in carrying out the terms of the
Agreement, However, the Consultant may keep one copy of such material for
archival purposes. The confidentiality obligations of the Consultant thereunder
shall survive for a period of five (5) years.

         (b) The Consultant represents that his performance of the terms of the
Agreement does not and will not conflict with the terms of any agreement to keep
in confidence proprietary information and trade secrets acquired in confidence
or in trust prior to his consulting relationship with the Company. The
Consultant will not disclose to the Company or induce the Company to use, any
confidential or proprietary information or material belonging to any third
party.

         (c) The Consultant represents that he is not presently retained by any
entity that manufactures or sells products competitive with those of the Company
and he agrees that he will not accept such retention during the term of this
Agreement without prior written approval of the Company.

         6. INVENTIONS.

         (a) The Consultant shall promptly and fully disclose to the Company any
and all inventions, improvements, discoveries, developments, original works of
authorship, trade secrets or other intellectual property conceived, developed or
reduced to practice by the Consultant during the term of the Agreement and in
any way relating to (1) the actual or anticipated research and development of
the Company, or (2) the services performed by the Consultant under this
Agreement (the "information"). The Consultant shall treat all of the information
as the proprietary property of the Company. The Consultant agrees to assign, and
does hereby assign, to the Company and its successors and assigns, without
further



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consideration, the Consultant's entire right, title and interest in and to the
Information whether or not patentable or copyrightable. The Consultant further
agrees to execute all applications for patents and/or copyrights, domestic or
foreign, assignments and other papers necessary to secure and enforce rights
related to the information. The parties acknowledge that all original works of
authorship which are made by the Consultant within the scope of his consulting
services which are protectable by copyright are "works made for hire", as that
term is defined in the United States Copyright Act (17 USCA Section 101).

         (b) The Consultant shall specifically describe and identify in Exhibit
A to this Agreement and all technology (i) which the Consultant intends to use
in performing under this Agreement (ii) which is either owned solely by the
Consultant or licensed to the Consultant with a right to sublicense, and (iii)
which is existence in the form of a writing or working prototype prior to the
effective date of this Agreement (Background Technology"). The Consultant hereby
grants to the Company a non-exclusive, royalty-free and worldwide right to use
and sublicense the use of any Background Technology for the purpose of
developing and marketing the Company's products, but not for the purpose of
marketing any Background Technology separate from the Company's products.

         (c) The Consultant warrants that he has good and marketable title to
all of the Information and that the Information shall be free and clear of all
liens, claims, encumbrances or demands of third parties, including any claims by
any such third parties of any right, title or interest in or to the Information
arising out of any trade secret, copyright or patent. The Consultant shall
indemnify, defend and hold harmless the Company and its officers, agents,
directors, employees, and customers from and against any claim, loss, judgment
or expense (including reasonable attorney's and expert witnesses' fees and cost)
resulting from or arising in any way out of any such claims by any third parties
which are based upon or are the result of any breach of the warranties contained
in the Section 6.

         7. TERMINATION. Either party may terminate this Agreement in whole or
part at its convenience upon 30 days written notice to the other party. Such
termination shall be effective in the manner and upon the date specified in said
notice and shall be without prejudice to any claims which one party may have
against the other. In the event of such termination the Company shall be
obligated to reimburse the Consultant for services actually performed by the
Consultant up to the effective date of termination. Termination shall not
relieve the Consultant of his continuing obligation under this Agreement,
including without limitation the requirements of Paragraphs 5 and 6 above.

         8. MISCELLANEOUS.

            (a) This Agreement shall be governed by and construed in accordance
with the laws of the State of California. The Federal and State courts



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within the State of California shall have exclusive jurisdiction to adjudicate
any dispute arising out of this Agreement. The parties consent to personal
jurisdiction of the Federal and State courts within California and service of
process being effective by registered mail sent to the address set forth at the
end of this Agreement.

            (b) This Agreement may not be and shall not be deemed or construed
to have been modified, amended, rescinded, canceled or waived in whole or in
part, except by written instruments signed by the partied hereto. No failure on
the part of either party to exercise, and no delay in exercising, any right or
remedy hereunder shall operate as a waiver thereof; nor shall any single or
partial exercise of any right or remedy hereunder preclude any other or further
exercise thereof or the exercise of any other right or remedy granted hereby or
by any related document or by law.

            (c) This Agreement, including the exhibit attached hereto and made a
part thereof, constitutes and expresses the entire agreement and understanding
between the parties. All previous discussions, promises, representations and
understandings between the parties relative to this Agreement, if any, have been
merged into this document. The provisions of Paragraphs 5 and 6 shall survive
the termination of this Agreement. The terms and provisions of this Agreement
shall be binding on and inure to the benefit of the parties, their heirs, legal
representatives, successors and assigns.

            (d) The Consultant may not subcontract all or any part of the
services to be provided hereunder without the prior written consent of the
Company.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first set forth above.


CARDIAC PATHWAYS CORPORATION
a Delaware Corporation

David W. Gryska                                EARLE CANTY

By:  /S/ David W. Gryska                       /s/ Earle Canty
     --------------------------------          --------------------------------
     Title: Chief Financial Officer            Signature

                                               --------------------------------
                                               Social Security Number

995 Benecia Avenue                             --------------------------------
Sunnyvale, CA 94086                            Street Address
408-737-0505                                   --------------------------------
408-737-1700 FAX                               City, State, Zip Code
                                               --------------------------------




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                          CARDIAC PATHWAYS CORPORATION
                              CONSULTING AGREEMENT
                                    EXHIBIT A


NAME OF CONSULTANT: Earle Canty

1.    DESCRIPTION OF CONSULTING SERVICES:

      -     Regulatory Consulting for a minimum of 20 hours per week.

2.    TERM OF AGREEMENT:

      6 months

3.    COMPANY CONTACT:

      Bill Starling or Debra Echt or other individuals Bill Starling may
      designate.

4.    CONSIDERATION FOR SERVICES:

      Consideration: Consultant will be paid $2,000 week (rate of $100 per
      hour). It is expected that consultant will provide the Company no less
      than 80 hours of consulting per month. Company guarantees the Consultant
      at least 80 hours of consulting fees per month. To the extent the
      Consultant provides less than 80 hours of work the unused hours will be
      carried forward to the next month. To the extent the Consultant works more
      than 80 hours per month and there are no unused credits the consultant
      will be paid at a rate of $100 per hour.

      Method of Payment and Accounting: The payments for the Consultant will be
      processed every 10 days in increments of $2,000 (i.e. consulting for the
      first week of the month will be paid by the 17th.) On the 5th day of the
      following month the Consultant shall provide the Company (Bill Starling) a
      detailed statement of consulting hours (i.e. hours by day and project).



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