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                                                                   EXHIBIT 10.20
                              EMPLOYMENT AGREEMENT

     THIS AGREEMENT is entered into as of July 18, 1997 by and between TIMOTHY
J. KILGALLON (the "Employee") and HEALTHKNOWLEDGE CORPORATION, a Delaware
corporation (the "Company").

     1.   Term of Employment.
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          (a) Effective Date. This Agreement shall be effective from July 18,
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1997 (the "Effective Date").

          (b) Term. The Company agrees to continue the Employee's Employment,
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and the Employee agrees to remain in Employment with the Company, from the
Effective Date until the earlier of;

               (i)  July 18, 2001; or

               (ii) The date when the Employee's Employment terminates pursuant
     to Subsections 1 (d), (e), (f) or (g) below.

          (c) Renewal. In the event that neither the Company nor Employee give
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notice to the other party of an intention to terminate this Agreement at least
30 days prior to the date set forth in clause (i) of Subsection 1(b) hereof,
this Agreement shall be automatically renewed for a one-year term. This
Agreement shall thereafter be automatically renewed for successive one-year
terms in the absence of 30-day notice by either party to the contrary.

          (d) Early Termination. Subject to Section 8, the Company may terminate
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the Employee's Employment without Cause by giving the Employee 30 days' advance
notice in writing. The Employee may terminate his Employment without Good Reason
by giving the Company 30 days' advance notice in writing. The Employee's
Employment shall terminate automatically in the event of his death. Any waiver
of notice shall be valid only if it is made in writing and expressly refers to
the applicable notice requirement of this Section 1.

          (e) Cause. The Company may terminate the Employee's Employment at any
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time upon reasonable notice for Cause. For all purposes under this Agreement,
"Cause" shall mean (i) a knowing failure by the Employee to comply with the
material policies of the Company, (ii) gross negligence of Employee which
results in a materially adverse impact to the Company, (iii) a breach of a
fiduciary duty to the Company, (iv) conviction of, or a plea of "guilty"

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or "no contest" to, a felony or (v) demonstrable and repeated (x) failure to
follow the directions of the Company's Board of Directors (the "Board") or (y)
failure to perform his obligations, duties or responsibilities hereunder, other
than a failure resulting from the Employee's complete or partial incapacity due
to physical or mental illness or impairment.

          (f) Good Reason. Employee may terminate his Employment at any time
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upon reasonable notice for Good Reason. For all purposes under this Agreement,
"Good Reason" shall mean (i) a substantial reduction in Employee's position or
authority at the Company, (ii) a more than 25 percent reduction in Base
Compensation or benefits, (iii) a failure to pay compensation payable hereunder
or (iv) the filing by the Company of bankruptcy proceedings.

          (g) Disability. The Company may terminate the Employee's active
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Employment due to Disability by giving the Employee 30 days' advance notice in
writing. For all purposes under this Agreement, "Disability" shall mean that the
Employee, at the time notice is given, has performed substantially none of his
duties under this Agreement for a period of not less than three consecutive
months as the result of his incapacity due to physical or mental illness. In the
event that the Employee resumes the performance of substantially all of his
duties hereunder before the termination of his active Employment under this
Subsection 1(g) becomes effective, the notice of termination shall automatically
be deemed to have been revoked.

          (h) Rights Upon Termination. Except as expressly provided in Section
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8, upon the termination of the Employee's Employment pursuant to this Section 1,
the Employee shall only be entitled to the compensation, benefits and
reimbursements described in Sections 3, 4, 5 and 6 for the period preceding the
effective date of the termination. The payments under this Agreement shall fully
discharge all responsibilities of the Company to the Employee.

     2.   Duties and Scope of Employment.
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          (a) Position. The Company agrees to employ the Employee as its
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President and Chief Executive Officer for the term of his Employment under this
Agreement ("Employment"). The Company agrees to use its best efforts to cause
the Employee to be nominated for election as a member of the Company's Board
throughout the term of his Employment.

          (b) Obligations. During the term of his Employment, the Employee shall
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devote his full business efforts and time to the Company and its subsidiaries
(if any). He shall not render services to any other person or entity without the
express prior approval of the Board. Such approval shall not be withheld
unreasonably, provided that service on the boards of directors of other
corporations

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will be approved only if (i) such other corporations are not engaged in
activities that are competitive, or potentially competitive, with the Company,
(ii) such other corporations are of a quality and stature commensurate, in the
sole judgment of the Board, with the Employee's position under this Agreement
and with the Company's objectives and (iii) the Employee will not be serving on
the boards of directors of more than three corporations (other than the
Company).

     3.   Compensation.
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          (a) Salary. During the term of his Employment, the Company agrees to
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pay the Employee as compensation for his services a base salary at the annual
rate of $144,000 or at such higher rate as the Company may determine from time
to time. Such salary shall be payable in accordance with the Company's standard
payroll procedures. (The annual compensation specified in this Section 3,
together with any increases in such compensation that the Company may grant from
time to time, is referred to in this Agreement as "Base Compensation.")
Employee's Base Compensation is retroactive to June 1, 1997.

          (b) Incentive Plan. Employee shall be eligible to receive, at the
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discretion of the Board, grants of stock options under incentive plans adopted
by the Board and approved by the Company's stockholders.

          (c) Bonus. Employee shall be eligible to receive an annual bonus of up
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to 60 percent of Base Compensation, such amount to be determined by the Board
and subject to the achievement of objectives to be determined by the Board no
later than 30 days prior to the commencement of each new year of Employment.

          (d) Closing Bonus. Employee hereby acknowledges receipt of a $50,000
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bonus paid by the Company following the closing of the sale of the Company's
Series A Preferred Stock to cover prior legal, travel and other expenses.

          (e) Cost of Living Adjustment. The Company shall pay to Employee
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$1,500 per month to offset the difference in cost of living from Atlanta to
Seattle. Such payments will terminate on the first anniversary of the Effective
Date.

          (f) Loan Forgiveness. Pursuant to the terms of the Stock Agreement (as
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defined in Section 7 below) and in connection with the purchase of Common Stock,
the Company has loaned to Employee $59,250.00. One-fourth of the principal
amount of such loan shall be forgiven on each of the first four anniversaries of
the Effective Date provided that Employee achieves certain annual objectives as
determined by the Board of Directors and set forth in a written notice to
Employee no later than (i) December 31, 1997, in the case of the first one-year

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period and (ii) 30 days prior to the commencement of each subsequent one-year
period. In the event Employee's Employment terminates after less than four
consecutive years of service with the Company, the unpaid balance of such loan
shall be due and payable in accordance with the terms of the promissory note
dated July 18, 1997 attached hereto and incorporated herein by reference. In the
event of a Change of Control with respect to the Company (as defined in Section
7(b) below), any unpaid balance of such loan shall be forgiven as of the date of
the closing of the transaction that results in a Change of Control. Employee
acknowledges that the forgiveness of such loan may result in taxable
compensation to Employee and may be subject to applicable withholding taxes.

     4.   Employee Benefits.
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          (a) Benefit Plans. During the term of his Employment, Employee shall
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be eligible to participate in the employee benefit plans maintained by the
Company, subject in each case to the generally applicable terms and conditions
of the plan in question and to the determinations of any person or committee
administering such plan.

          (b) Disability Insurance. The Company will provide to Employee
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additional disability insurance coverage such that 75 percent of Base
Compensation is covered.

          (c) Vacation. Employee will be entitled to four weeks of vacation for
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each full year of Employment. The maximum vacation Employee can accrue in any
year is four weeks. If Employee has not used his four weeks of vacation by the
end of the Employment year, he will not lose any accrued vacation, but vacation
will cease to accrue until accrued vacation is below the four week cap.

     5.  Business Expenses.
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     During the term of his Employment, the Employee shall be authorized to
incur necessary and reasonable travel, entertainment and other business expenses
in connection with his duties hereunder. The Company shall reimburse the
Employee for such expenses upon presentation of an itemized account and
appropriate supporting documentation, all in accordance with the Company's
generally applicable policies.

     6.  Relocation Expenses.
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     The Company will reimburse the reasonable moving expenses, not to exceed in
the aggregate $75,000, of Employee's relocation of his household from Atlanta to
Seattle, including real estate closing costs and commission on sale of his home
in Atlanta and the moving of household goods, family and automobile. If

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Employee's Employment is terminated for Cause or Employee resigns without Good
Reason prior to the first anniversary of the Effective Date, Employee will repay
50 percent of the relocation expenses paid by the Company.

     7.   Stock Vesting.
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          (a) Acceleration. Employee and the Company are parties to that certain
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Common Stock Purchase Agreement dated as of July 17, 1997 (the "Stock
Agreement"), which provides for a right of repurchase in favor of the Company
with respect to 750,000 shares of the Company's Common Stock purchased by
Employee thereunder, which right of repurchase lapses ratably on a monthly basis
over a four-year period, subject to a one-year cliff. The Company agrees that,
in the event that the Company is subject to a Change in Control, such right of
repurchase shall lapse as to all then remaining unvested shares.

          (b) Definition of Change in Control. For all purposes under this
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Agreement, "Change in Control" shall mean a consolidation, merger or other
reorganization of the Company with or into another corporation or other entity
or person in which the Company shall not be the continuing or surviving entity
of such merger, consolidation or reorganization, or the sale of all or
substantially all of the Company's properties and assets to any other person, or
any transaction or series of related transactions by this corporation in which
an excess of 50% of this corporation's voting power is transferred, unless the
Company's stockholders of record immediately prior to such merger,
consolidation, reorganization, sale or transaction are holders of more than 50%
of the voting equity securities of the surviving corporation.

     8.   Involuntary or Constructive Termination.
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          (a)  Salary and Benefit Continuation. Subject to Subsection 8(b)
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below, the Company shall continue (i) to pay the Employee's Base Compensation
(at the annual rate then in effect), (ii) to provide the benefits described in
Subsections 4(a) and 4(b) and (iii) to vest Employee's shares of Common Stock
under the Stock Agreement for 12 months following a termination of Employment,
if:

               (i) At any time during the term of this Agreement, the Company
     terminates the Employee's Employment without his consent for any reason
     other than Cause or Disability; or

               (ii) During the term of this Agreement, the Employee voluntarily
     resigns his Employment for Good Reason.

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The payments under this Subsection 8(a) shall cease in the event of the
Employee's death.

          (b) Mitigation. The payments under Subsection 8(a) above shall be
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reduced on a dollar-for-dollar basis by any other compensation earned by the
Employee for personal services performed as an employee or independent
contractor during the 12-month period following the termination of his
Employment, including (without limitation) deferred compensation. The Employee
shall apply his best efforts to seek and obtain other employment or consulting
engagements, whether on a full- or part-time basis, during such period in order
to mitigate the Company's obligations under Subsection 8(a) above. The Employee,
at reasonable intervals, shall report to the Company-with respect to such
efforts and any compensation earned during such period.

     9.   Successors.
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          (a) Company's Successors. The Company shall use its best efforts to
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provide that any successor (whether direct or indirect and whether by purchase,
lease, merger, consolidation, liquidation or otherwise) to all or substantially
all of the Company's business and/or assets, by an agreement in substance and
form satisfactory to the Employee, will assume this Agreement and agree
expressly to perform this Agreement in the same manner and to the same extent as
the Company would be required to perform it in the absence of a succession. For
all purposes under this Agreement, the term "Company" shall include any
successor to the Company's business and/or assets which executes and delivers
the assumption agreement described in this Subsection 9(a) or which becomes
bound by this Agreement by operation of law.

          (b) Employee's Successors. This Agreement and all rights of the
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Employee hereunder shall inure to the benefit of, and be enforceable by, the
Employee's personal or legal representatives, executors, administrators,
successors, heirs, distributees, devisees and legatees.

     10.   Miscellaneous Provisions.
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          (a) Notice. Notices and all other communications contemplated by this
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Agreement shall be in writing and shall be deemed to have been duly given when
personally delivered or when mailed by U.S. registered mail, return receipt
requested and postage prepaid. In the case of the Employee, mailed notices shall
be addressed to him at the home address which he most recently communicated to
the Company in writing. In the case of the Company, mailed notices shall be
addressed to its corporate headquarters, and all notices shall be directed to
the attention of its Secretary.

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          (b) Waiver. No provision of this Agreement shall be modified, waived
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or discharged unless the modification, waiver or discharge is agreed to in
writing and signed by the Employee and by an authorized officer of the Company
(other than the Employee). No waiver by either party of any breach of, or of
compliance with, any condition or provision of this Agreement by the other party
shall be considered a waiver of any other condition or provision or of the same
condition or provision at another time.

          (c) Whole Agreement; Modifications. No agreements, representations or
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understandings (whether oral or written and whether express or implied) which
are not expressly set forth in this Agreement, the Stock Agreement or the
Confidentiality, Inventions and Noncompetition Agreement dated as of July 18,
1997 between the parties (the "Inventions Agreement") have been made or entered
into by either party with respect to the subject matter hereof. This Agreement,
the Stock Agreement and the Inventions Agreement contain the entire
understanding of the parties with respect to the subject matter hereof. A
modification of this Agreement shall be valid only if it is made in writing and
executed by both parties hereto.

          (d) Withholding Taxes. All payments and imputed payments made under
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this Agreement shall be subject to reduction to reflect taxes or other charges
required to be withheld by law.

          (e) Choice of Law. The validity, interpretation, construction and
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performance of this Agreement shall be governed by the laws of the State of
Washington.

          (f)  Severability. The invalidity or unenforceability of any provision
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or provisions of this Agreement shall not affect the validity or enforceability
of any other provision hereof, which shall remain in full force and effect.

          (g)  Dispute Resolution Procedure.
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               (i) The parties agree that any dispute arising out of or related
     to the Employment relationship between them, including but not limited to
     common law or statutory claims for discrimination, wrongful discharge,
     breach of contract, breach of public policy, physical or mental harm or
     distress, unpaid wages or any other dispute, shall be resolved by binding
     arbitration, except where the law specifically forbids the use of
     arbitration as a final and binding remedy.

               (ii) The party claiming to be aggrieved shall furnish to the
     other party a written statement of the grievance identifying any witnesses
     or documents that support the grievance and the relief requested or
     proposed.

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               (iii)  If the other party does not agree to furnish the relief
     requested or proposed, or otherwise does not satisfy the demand of the
     party claiming to be aggrieved, the parties shall submit the dispute to
     nonbinding mediation before a mediator to be jointly selected by the
     parties. The Company will pay the cost of the mediation.

               (iv) If the mediation does not produce a resolution of the
     dispute, the parties agree that the dispute shall be resolved by final and
     binding arbitration in Seattle, Washington. The parties shall attempt to
     agree to the identity of an arbitrator, and, if they are unable to do so,
     the parties agree to assignment of an arbitrator from Judicial Arbitration
     and Mediation Services (JAMS). The arbitrator shall have the authority to
     determine whether the conduct complained of in section (g)(ii) violates the
     rights of the complaining party and, if so, to grant any relief authorized
     by law; provided, however, that the employee and the Company agree that for
     violations of the employee's trade secret obligations, the Company reserves
     the right to seek preliminary injunctive relief in court in order to
     preserve the status quo or prevent irreparable injury before the matter can
     be heard in arbitration. The arbitrator shall not have the authority to
     modify, change or refuse to enforce the terms of this Agreement. In
     addition, the arbitrator shall not have the authority to require the
     Company to change any lawful policy or benefit plan. The hearing shall be
     transcribed. The Company shall bear the costs of the arbitration if the
     Employee prevails. If the Company prevails, the Employee will pay half the
     cost of the arbitration or $500, whichever is less. Each party shall be
     responsible for paying its own attorneys fees, unless the law provides
     otherwise. Arbitration shall be the exclusive final remedy for any dispute
     between the parties, and the parties agree that no dispute shall be
     submitted to arbitration where the party claiming to be aggrieved has not
     complied with the preliminary steps provided for in clauses (ii) and (iii)
     above.

               (v) Employee acknowledges that he has carefully read this
     arbitration agreement and understands it, and is entering into the
     agreement voluntarily after a reasonable period of time to consider it and
     review it with personal legal counsel. Employee also acknowledges he may be
     giving up the opportunity to bring claims before a court or jury, and does
     so in order to gain the benefits of a speedy, impartial and cost-effective
     resolution procedure.

          (h) No Assignment. The rights of any person to payments or benefits
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under this Agreement shall not be made subject to option or assignment, either
by voluntary or involuntary assignment or by operation of law, including
(without limitation) bankruptcy, garnishment, attachment or other creditor's
process, and any action in violation of this Subsection 10(h) shall be void.

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     IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the
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case of the Company by its duly authorized officer, as of the day and year first
above written.



                                /s/ Timothy J. Kilgallon
                                ------------------------
                                Timothy J. Kilgallon

                                HEALTHKNOWLEDGE CORPORATION



                                By   /s/ Dennis P. Schmuland
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                                Dennis P. Schmuland, M.D.
                                Chairman of the Board

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