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                                                                    Exhibit 10.2


                        STOCK PURCHASE AND SALE AGREEMENT

         This Stock Purchase and Sale Agreement, dated as of May 20, 2003, is
entered into by and between HealthGate Data Corp. ("HealthGate") and Computer
Sciences Corporation, as successor to Nichols Research Corporation ("Seller").

         Buyer and Seller agree as follows:

         1. Seller has had the opportunity to review HealthGate's filings with
the U.S. Securities and Exchange Commission and otherwise make detailed inquiry
concerning HealthGate. Seller acknowledges that it has had the opportunity to
ask questions of and receive answers from HealthGate.

         2. Effective May 20, 2003, HealthGate is buying from Seller and Seller
is selling to HealthGate 599,403 shares of common stock of HealthGate Data
Corp., for the price of $0.08 per share or a total purchase price of $47,952.24.

         3. HealthGate shall promptly deliver to Rich, May, a Professional
Corporation a check for $47,952.24 payable to Computer Sciences Corporation.

         4. Seller shall promptly deliver stock certificate No HG 242
representing 599,403 shares of HealthGate common stock, and a fully-executed
stock power, to transfer 599,403 shares of HealthGate common stock to HealthGate
to:
         Rich May, a Professional Corporation
         176 Federal Street
         Boston, MA 02110
         Attn: Stephen M. Kane

         5. Upon receipt of the documents described in Section 4, HealthGate
shall instruct Rich May, a Professional Corporation to promptly deliver the
$47,952.24 payment check to:
         Computer Sciences Corporation
         Corporate Headquarters
         2100 East Grand Avenue
         El Segundo, CA 90245
         Attn: Stefanie Forsey

         6. Both parties will fully cooperate with each in connection with the
purchase, sale and transfer of ownership of 599,403 shares of HealthGate common
stock, including executing and delivering further instruments of transfer and
assignment.

         7. HealthGate Data Corp. represents and warrants that it is duly
authorized to complete this transaction and that the individual signing below on
behalf of HealthGate has full power and authority to bind the corporation.

         8. Counterparts. This Agreement may be executed in any number of
counterparts and each such counterpart shall for all purposes be deemed to be an
original, and all such counterparts shall together constitute but one and the
same instrument.

                    [SIGNATURES APPEAR ON THE FOLLOWING PAGE]


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         IN WITNESS WHEREOF, the undersigned have hereunto set their hands as of
the day and year first above written.

HealthGate Data Corp                             Computer Sciences Corporation
                                                 ("Seller")

By: /s/ William S. Reece                         By:    /s/ H D Fisk
    ------------------------                            -----------------------
    William S. Reece                             Name:  H D Fisk
    President and CEO                                   -----------------------
                                                 Title: Vice President
                                                        -----------------------