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                                                                   EXHIBIT 10.30


June 1, 1992

Richard Riley
469 Valley Wood Circle
Golden Valley, Minnesota 55422


Dear Rick:

This letter, when signed by the you, will constitute an agreement between
Cardiac Pathways Corporation (the "Company") and the you (the "Executive")
concerning your employment and will supercede all previous agreements and
discussions.

1.      The Company hereby hires the Executive and the Executive hereby accepts
        employment as Vice President Software Engineering of the Company.

2.      The Company agrees to pay the Executive a monthly base salary of
        $9,166.67 payable in accordance with the Company's standard payroll
        policy.

3.      The Executive's employment with the Company will be at-will and may be
        terminated by the Executive or the Company at any time.

4.      The Company will issue to the Executive an option exercisable for 75,000
        shares of Common Stock at its fair market value on the date of the
        grant. The current fair market value of Common Stock is $0.15. The grant
        of this option is subject to the Board of Directors' approval. The stock
        option will vest over a four year period with 12/48 of the shares
        vesting on the Executive's one year anniversary date with the Company
        and an additional 1/48 of the total number of shares vesting at the end
        of each full month thereafter. The stock option shall be represented by
        the Company's standard form of stock option agreement. This vesting
        schedule could be modified by the terms outlined in Sections 5 and 6.

5.      a.     The term of this Agreement shall commence on July 1, 1992 and
               shall continue until terminated by either party in accordance
               with the provisions of this Section 8.

        b.     This Agreement may be terminated by the Company at any time for
               Justifiable Cause (as hereinafter defined) provided that the
               Company shall pay the Executive an amount equal to the sum of his
               then current monthly base salary as a severance payment for one
               month following

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Rick Riley
June 1, 1992
Page Two


               the date of termination. For the purpose of this Agreement, the
               term "Justifiable Cause" shall include the occurrence of any of
               the following events: (i) the Executive's conviction for, or plea
               of nolo contendere, a felony or a crime involving moral
               turpitude, (ii) the Executive's commission of an act of personal
               dishonesty or breach of fiduciary duty involving personal profit
               in connection with the Company, (iii) the Executive's commission
               of an act, or failure to act, which the Executive's supervisor at
               the Company shall reasonably have found to have involved
               misconduct or gross negligence on the part of the Executive, in
               the conduct of his duties hereunder, (iv) habitual absenteeism,
               alcoholism or drug dependency on the part of the Executive which
               interfere with the performance of his duties hereunder, (v) the
               Executive's willful and material breach or refusal to perform his
               services as provided herein, (vi) any other material breach of
               this Agreement or (vii) the willful and material failure or
               refusal to carry out a direct request of the Executive's
               supervisor. The payment to the Executive of the severance payment
               described in this Section 5(b) will discharge all of the
               Company's obligations to the Executive.

        c.     This Agreement may be terminated by the Company at any time
               without justifiable Cause provided that the company shall pay the
               Executive an amount equal to the sum of his then current monthly
               base pay as a severance payment for a period of six months
               following the date of termination, or until the Executive finds
               other employment whichever is shorter. Any payments made pursuant
               to this Section 5(c) shall be reduced to the extent the Executive
               receives any other earnings related to employment or consulting
               services or other unemployment or disability compensation during
               the six month period. The payment to the Executive of the
               severance payment described in this Section 5(c) will discharge
               all of the Company's obligations (subject to the provisions noted
               in Section 6) to the Executive. If such termination takes place
               in the first year of the Executive's employment with the company,
               the incentive stock option will vest at 1/48 per month, and the
               one year waiting period pursuant to Section 4 shall be waived.

        d.     This Agreement may be terminated by the Executive at any time
               upon 30 days written notice, in which case the Company shall have
               no severance or other obligations to the Executive.


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Rick Riley
June 1, 1992
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6.      Notwithstanding anything set forth in this Section 6, upon the
        Executive's involuntary termination of employment from the Company (for
        any reason other than for Justifiable Cause) on or after an Acquisition
        (as defined below), the 75,000 shares of Common Stock described in
        Section 4 above shall be fully and immediately exercisable. For purposes
        of this Section 6, an Acquisition shall be defined as a merger,
        reorganization, or sale of all or substantially all of the assets of the
        Company in which the shareholders of the Company immediately prior to
        the transaction possess less than fifty percent (50%) of the voting
        power of the surviving entity (or its parent) immediately after the
        transaction. The resignation of the Executive after a Constructive
        Termination (as defined below) shall be treated as an involuntary
        termination of employment under this Section 6. For purposes of this
        Section 6, a Constructive Termination shall mean a material reduction in
        salary or benefits, a material change in responsibilities, or a
        requirement to relocate, except for office relocations that would not
        increase the Executive's one-way commute distance by more than
        thirty-five (35) miles.

7.      As a condition of the Executive's employment, the Executive will also be
        required to execute the Company's standard Proprietary Information
        Agreement, a copy of which is enclosed with this letter.

8.      As additional compensation, the Company will pay up to $2,000 per month,
        less applicable withholding to the Executive for the Executive's
        temporary living expenses including food, laundry and rent for an
        apartment or home in the San Francisco Bay area. The temporary living
        expense allowance will terminate when both of the Executive's
        Minneapolis homes have sold, up to a maximum of twelve months. The
        Company will also pay the cost of several round-trip airplane tickets to
        Minneapolis to expedite the transition to the Bay area.

9.      The Company will also pay the following expenses, to help move the
        Executive to the Bay area:

        a.     All expenses incurred in moving the Executive's personal
               belongings, from the Minneapolis area to the San Francisco Bay
               area;

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Rick Riley
June 1, 1992
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        b.     Real estate commissions paid by the Executive to the Executive's
               real estate broker in connection with the sale of the Executive's
               most recently purchased home in Minneapolis;

        c.     Closing costs up to $10,000 on the purchase of a residential
               dwelling in the San Francisco Bay area during the Executive's
               tenure at the Company.

        d.     The Executive agrees to relocate to the Bay area and start work
               on or before August 3, 1992.

10.     After the Executive has purchased a home in the San Francisco Bay area,
        the Company will lend the Executive each month for a maximum period of
        sixty (60) months an amount equal to the difference between the
        Executive's monthly mortgage for the Executive's current residence and
        the monthly mortgage payment for the Executive's home in the San
        Francisco Bay area, up to a maximum of $1,000 per month. This loan will
        be due on the earlier of (i) five years from the date of the first
        monthly loan, or (ii) six months after the termination of the
        Executive's employment with the Company. At the Executive's option, the
        loan may be structured in one of two ways. First, it can be a loan
        bearing interest at the applicable federal rate as defined in the
        Internal Revenue Code of 1986 and the regulations thereunder, or second,
        it can be an interest free loan secured by a trust deed on the
        Executive's new residence.

If you are in agreement with this proposal, please execute a copy of this letter
and the Proprietary Information Agreement and return them to me as soon as
possible.

Best personal regards,


Cardiac Pathways Corporation                 Acknowledged and Accepted


By: /s/ WILLIAM N. STARLING                  /s/ RICHARD RILEY
   --------------------------------          -----------------------------------
   William N. Starling                       Richard Riley
   President