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                                                                   EXHIBIT 10.17

October 28, 1999



Ms. Kathleen Harris Pena
Vice President
MEDIBUY.COM
7777 Alvarado Road
Suite 401
La Mesa, California 91941

Dear Ms. Pena:

MEDIBUY.COM and Ernst & Young LLP (E&Y) began discussions in September 1999 to
explore ways in which we could work together to impact the success of
MEDIBUY.COM's business plan as it prepares for its Initial Public Offering.
Through these efforts we have jointly identified two critical projects where
MEDIBUY.COM is interested in obtaining E&Y's professional assistance.

The purpose of this letter is to authorize the immediate deployment of E&Y's
resources to these specific projects. This letter outlines the scope of services
for the projects requiring immediate launch, professional fees, and other terms
of our engagement.

SCOPE OF SERVICES

As a result of our discussions we have jointly determined the immediate need for
the following two projects in which E&Y will provide professional services
assistance:

        - Buyer Implementation

        - Supplier Implementation

As a result of our ongoing relationship and collaboration, E&Y began Buyer
Implementation planning in September 1999. The work completed by E&Y for
MEDIBUY.COM prior to this letter will be included in the deliverables and fees.

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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 2


BUYER IMPLEMENTATION

E&Y's assistance includes developing the implementation approach for the rollout
of eRFP and eAuction to MEDIBUY.COM buyer sites, coordinating and deploying
resources to implement the tools and educate buyers, and providing buyer
assistance/coaching to begin utilization of the tools.

MEDIBUY.COM has identified a number of sites where eRFP and eAuction will be
implemented. To expedite this process, E&Y will provide staffing assistance to
support the deployment to 50 sites by December 15th, 1999. Our ability to
accomplish this objective is dependent upon MEDIBUY.COM identifying target
sites, obtaining buyer commitments and scheduling 10 to 15 sites per week
beginning on November 1st, 1999. E&Y will assign eight dedicated staff to
provide training support in the activation and use of the above MEDIBUY.COM
products. The deliverables for this project will include:

        - Completion of the eRFP/eAuction Buyer Implementation Strategy; and

        - Hospital site visits and physical implementation at sites identified
          by MEDIBUY.COM.

SUPPLIER IMPLEMENTATION

Our work effort will consist of developing an implementation strategy for
suppliers to use eRFP in responding to purchasing department requests,
providing staffing support to register suppliers based upon criteria specified
by MEDIBUY.COM, and assisting in the deployment of MEDIBUY.COM to the supplier
communities.

We understand that MEDIBUY.COM has identified approximately 18,000 suppliers of
which 1,500 are registered to use the eRFP and related products. E&Y will assign
four dedicated staff to provide logistical and staffing support in order to
register as many additional vendors as possible by December 15th, 1999. Our
ability to achieve this objective will be dependent upon MEDIBUY.COM providing
supplier lists that are relevant to their customers as well as technical and
training support required to activate the suppliers.

The deliverables for this project will include:

        - Completion of the Supplier Implementation Strategy; and

        - High-level implementation script initially for current and prospective
          suppliers.


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 3

PROJECT TEAM

This is a significant project for both MEDIBUY.COM and E&Y. It is important that
the appropriate focus and direction be provided at both the project and
relationship levels. We will staff this engagement immediately by complementing
our existing team with additional E&Y staff. To ensure your continued
satisfaction with our service, we have established the leadership team
consisting of the following individuals.

GARY DOWLING, SENIOR MANAGER, will be the Alliance Executive for E&Y. Gary has
extensive knowledge of supply chain, health care and eCommerce. In addition he
has a strong existing knowledge of MEDIBUY.COM's executives and their goals.

BOB SKOK, PRINCIPAL, will serve as Engagement Executive for this project and
will be responsible for the overall conduct of our services under this
agreement. Bob will work closely with all members of our leadership team to
monitor the progress and quality of our assistance.

MICHAEL BROOKS, SENIOR MANAGER, will serve as Engagement Director. In this role,
he will have overall responsibility for E&Y's engagement execution, work closely
with MEDIBUY.COM's leadership, monitor progress toward project objectives and
actively participate in project design and execution.

ANGELA CHEUNG, MANAGER, and RICHARD PHILLIPS, MANAGER, will serve as Project
Managers for the Buyer and Supplier implementations, respectively. They will be
responsible for overall project management of E&Y's day-to-day project
activities. They will also be aligned closely with MEDIBUY.COM's project
leadership to help facilitate progress toward project objectives.

PROJECT TIMING AND FEES

As previously discussed, we have already initiated components of this work in
September and October. We are prepared to begin this project immediately upon
MEDIBUY.COM's approval to proceed as indicated by returning a signed copy of
this letter. Our assistance will continue through December l5th 1999.

Based on our proposed scope and anticipated level of participation, our
professional fees for buyer and supplier implementation will be $ 875,000 for
work performed between October 16th and December 15th. Our professional fees are
based on a time and materials basis driven by the actual time spent by the
assigned consultants. In the event changes in scope are identified or if
scheduling difficulties beyond our control impact the buyer & seller
implementations, we will notify you as soon as possible to discuss the impact on
the projects success and related professional fees and expenses. In addition to
our professional fees, it is our practice to bill for project related expenses
such as transportation, meals and lodging at our actual costs. Professional fees
for the buyer and


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 4


supplier implementations will be invoiced in two equal amounts of $437,500 on
the November 1st and December 1st. Expenses will be invoiced, monthly. All
invoices are due and payable by the fifteenth of the month.

Lastly, upon signing this agreement we will invoice MEDIBUY.COM for $270,000 in
professional fees and expenses related to work E&Y performed prior to October
15th at your request.

EXCLUSIVITY OF RELATIONSHIP

During the term of this agreement, E&Y agrees to not consult with the following
named competitors, related to the health provider supply/procurement ecommerce
market space, Neoforma and Global Village. Should the relationship between
MEDIBUY.COM and E&Y continue beyond the term of this agreement, at a substantial
and increasing level, E&Y also agrees to not consult with the previously named
competitors.

At the conclusion of this Agreement, or any extensions of the Agreement, E&Y
agrees to not consult with the named competitors previously mentioned for a
period of time equal to the duration of this Agreement, or any extensions, not
to exceed six (6) months.

This engagement will be governed by the Terms and Conditions specified in
Exhibit A included with this agreement.

                                 * * * * * * *

We look forward to working with MEDIBUY.COM on these important projects. To
indicate your acceptance of this engagement letter and authorization to proceed,
please sign below and return an original to Gary Dowling. Should any questions
arise, please contact Gary at (404) 817-5446.


Very truly yours,

[ ]  [ ]

AGREED TO AND ACCEPTED BY MEDIBUY.COM:

NAME: /s/ KATHLEEN HARRIS PENA
     ------------------------------
          KATHLEEN HARRIS PENA

TITLE:    Vice President                    DATE: 10-29-99
      -----------------------------
          VICE PRESIDENT

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                         EXHIBIT A TERMS AND CONDITIONS

I. Agreement. It is agreed that ERNST & YOUNG LLP ("E&Y") will provide the
consulting services (the "Services") described in the accompanying Letter to
which this Exhibit A is attached (such accompanying Letter and this Exhibit A,
collectively, this "Agreement"), to the client named in this Agreement (the
"Client"), as an independent contractor and for the fees set forth in this
Agreement. This Agreement constitutes the entire and sole agreement between
Client and E&Y, and merges all prior and contemporaneous communications with
respect to the subject matter hereof This Agreement shall not be modified or
assigned except by later written agreement signed by both parties. Nothing
contained herein shall be construed to create an employment or principal-agent
relationship or joint venture between E&Y and Client, and neither party shall
have the right, power or authority to obligate or bind the other in any manner
whatsoever.

II. Changes and Delays.

        A. Changes in scope of the Services dictated by Client and changing
conditions of law or schedule delays or other events beyond E&Y's reasonable
control, including events described below, may require contract price and/or
date of performance revisions to be agreed upon by both parties. In the event
that performance on the part of either party is delayed or suspended as a result
of circumstances beyond its reasonable control such as Acts of God or other
force majeure event, and without its fault or negligence, then the period of
performance and term of this Agreement shall be extended to the extent of any
such delay and neither party shall incur any liability to the other party as a
result of such delay or suspension.

        B. E&Y's performance hereunder is contingent upon the cooperation of
Client, including the supply to E&Y of adequate resources and accurate
information in connection with this Agreement. If any delays in E&Y's
performance occur as a result of failure or untimely performance by Client
and/or suppliers, the term of this Agreement shall be extended to the extent of
any such delay and E&Y shall not incur any liability to Client as a result of
such delay. If such delays last for thirty days or more, E&Y shall be entitled
to terminate this Agreement by giving written notice to Client, such termination
to be effective on the date indicated in said notice. E&Y's entitlement to
payment of fees and reimbursement of expenses in the event of termination under
this provision shall be governed by Paragraph VII below.

III. Warranty and Liability.

        A. E&Y will exercise due professional care and competence in the
performance of the Services.

        B. To the maximum extent permitted by law, E&Y's liability, regardless
of whether such liability is based on breach of contract, tort, strict
liability, breach of


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 6


warranties, failure of essential purpose or otherwise, under this Agreement or
with respect to the Services shall be limited to the amount of fees actually
paid by Client to E&Y under this Agreement. The foregoing limitation shall not
apply to the extent damages are directly caused by E&Y's willful misconduct or
gross negligence. If E&Y is working on a multi-phase engagement for Client,
E&Y's liability shall be limited to the amount actually paid to E&Y for that
particular phase that gives rise to the liability.

        C. Neither party shall be liable for consequential, incidental,
indirect, punitive or special damages (including loss of profits, data, business
or goodwill), regardless of whether such liability is based on breach of
contract, tort, strict liability, breach of warranties, failure of essential
purpose or otherwise, and even if advised of the likelihood of such damages.
Client's recourse with respect to any liability or obligation of E&Y hereunder
shall be limited to the assets of E&Y, and Client shall have no recourse
against, and shall bring no claim against, any partner of E&Y or any of the
assets thereof.

        D. EXCEPT AS OTHERWISE STATED ABOVE, E&Y MAKES NO WARRANTIES, OF ANY
KIND OR NATURE, WHETHER EXPRESS OR IMPLIED INCLUDING, BUT NOT LIMITED TO,
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE, OR
WARRANTIES OF ANY PRODUCTS OR SERVICES PROVIDED BY A THIRD PARTY VENDOR.

IV. Client Cooperation. Client agrees to provide E&Y, in a timely fashion, with
all information reasonably required for the performance of the Services, with
any new information that may be necessary to E&Y's understanding of the
Services, and with adequate resources and personnel to facilitate the
performance of the Services.

        V. Confidentiality.

        A. Neither party shall disclose Confidential Information (as hereinafter
defined) of the other party. The receiving party shall use the same degree of
care as it uses to protect its own confidential information of like nature, but
no less than a reasonable degree of care, to maintain in confidence the
confidential information of the disclosing party. The foregoing obligations
shall not apply to any information that (i) is at the time of disclosure, or
thereafter becomes, part of the public domain through a source other the
receiving party, (ii) is subsequently learned from a third party that does not
impose an obligation of confidentiality on the receiving party, (iii) was known
to the receiving party at the time of disclosure, (iv) was generated
independently by the receiving party without reference to Confidential
Information, or (v) is required to be disclosed by law, subpoena or other
process.

        B. For the purpose of this Section V, Confidential Information shall
mean any information identified by either party as "Confidential" and/or
"Proprietary", or which,


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 7


     B. For the purpose of this Section V, Confidential Information shall mean
any information identified by either party as "Confidential" and/or
"Proprietary", or which, under all of the circumstances, ought reasonably to be
treated as confidential and/or proprietary, including this Agreement.

VI. Approval. Deliverables and reports provided to Client by E&Y will be
reviewed and approved by the representatives appointed by Client. Client shall
accept or reject each deliverable or report within seven (7) days of receipt.
Each such deliverable and report shall be conclusively deemed accepted unless
rejected in writing within seven (7) days following delivery thereof. Acceptance
shall not be unreasonably withheld. Any rejection shall be in writing and
specifically state the matter in which the deliverable or report is materially
defective. For purposes of this Agreement, seven (7) days shall constitute a
reasonable period for the Client to determine acceptance of E&Y's performance.
E&Y shall use commercially reasonable efforts to make the modifications
necessary to correct such material defects.

VII. Term and Termination. This Agreement will terminate when the Services have
been completed. Either party may terminate this Agreement in the event of the
breach by the other party of this Agreement, which breach is not cured within
thirty (30) days after notice by the non-breaching party. Client shall pay E&Y
for work-in-progress, Services and expenses incurred prior to the effective date
of termination. Upon termination of this Agreement, the parties shall return
Confidential Information received from the other, except that E&Y may retain a
set of its working papers even if they contain Confidential Information.

VIII. Taxes and Payment. Any applicable taxes incurred in connection with the
Services or Deliverables (except for taxes imposed on income) will be billed to,
and paid by, Client, in addition to fees and expenses. Payment by Client of
E&Y's fees, expenses and any applicable taxes shall be due upon receipt of E&Y's
invoice.

IX. Conflict and Survival. In the event of any conflict, ambiguity or
inconsistency between this Exhibit A and any other document to which this
Exhibit A may be annexed or which may be annexed to this Exhibit A, including
any terms and conditions on Client's purchase orders or otherwise, the terms and
conditions of this Exhibit A shall govern. The provisions of this Agreement
which give the parties rights beyond termination of this Agreement will survive
any termination of this Agreement.

X. Non-Solicitation of Personnel. Client shall not solicit for employment or
hire any E&Y employee who is involved in the performance of this Agreement
during the term of this Agreement and for a period of six (6) months following
its termination except as may be agreed to in writing by both parties.


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 4


XI. Severability. If any portion of this Agreement is held to be void, invalid,
or otherwise unenforceable, in whole or part, the remaining portions of this
Agreement shall remain in effect.

XII. Mediation/Arbitration. Any controversy or claim arising out of or relating
to this Agreement or the Services (including any such matter involving any
parent, subsidiary, affiliate, successor in interest, or agent of the Client or
of E&Y) shall be submitted first to voluntary mediation, and if mediation is not
successful, then to binding arbitration, in accordance with the dispute
resolution procedures set forth in Annex 1 attached hereto. Judgment on any
arbitration award may be entered in any court having proper jurisdiction.

XIII. Third Party Beneficiaries. This Agreement and all services to be provided
hereunder are for the sole benefit of the parties hereto and nothing herein
expressed or implied shall give or be construed to give to any person or entity,
other than the parties hereto, any legal or equitable rights whatsoever. E&Y
does not assume and shall not have any duty or obligation to any other person or
entity.

ANNEX 1
Dispute Resolution Procedures

The following procedures shall be used to resolve any controversy or claim
("dispute") as provided in this Agreement. If any of these provisions are
determined to be invalid or unenforceable, the remaining provisions shall remain
in effect and binding on the parties to the fullest extent permitted by law.

Mediation

A dispute shall be submitted to mediation by written notice to the other party
or parties. In the mediation process, the parties will try to resolve their
differences voluntarily with the aid of an impartial mediator, who will attempt
to facilitate negotiations. The mediator will be selected by agreement of the
parties. If the parties cannot agree on a mediator, a mediator will be
designated by the American Arbitration Association ("AAA") or JAMS/Endispute at
the request of a party. Any mediator so designated must be acceptable to all
parties.

The mediation will be conducted as specified by the mediator and agreed upon by
the parties. The parties agree to discuss their differences in good faith and to
attempt, with the assistance of the mediator, to reach an amicable resolution of
the dispute.

The mediation will be treated as a settlement discussion and therefore will be
confidential. The mediator may not testify for either party in any later
proceeding relating to the dispute. No recording or transcript shall be made of
the mediation proceedings.


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                               PAGE 9


Each party will bear its own costs in the mediation. The fees and expenses of
the mediator will be shared equally by the parties.


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MS. KATHLEEN PENA                                               OCTOBER 25, 1999
MEDIBUY.COM                                                              PAGE 10


Arbitration

If a dispute has not been resolved within 90 days after the written notice
beginning the mediation process (or a longer period, if the parties agree to
extend the mediation), the mediation shall terminate and the dispute will be
settled by arbitration. The arbitration will be conducted in accordance with the
procedures in this document and the Arbitration Rules for Professional
Accounting and Related Services Disputes of the AAA ("AAA Rules"). In the event
of a conflict, the provisions of this document will control.

The arbitration will be conducted before a panel of three arbitrators,
regardless of the size of the dispute, to be selected as provided in the AAA
Rules. Any issue concerning the extent to which any dispute is subject to
arbitration, or concerning the applicability, interpretation, or enforceability
of these procedures, including any contention that all or part of these
procedures are invalid or unenforceable, shall be governed by the Federal
Arbitration Act and resolved by the arbitrators. No potential arbitrator may
serve on the panel unless he or she has agreed in writing to abide and be bound
by these procedures.

Unless provided otherwise in the Agreement, the arbitrators may not award
non-monetary or equitable relief of any sort. They shall have no power to award
(i) damages inconsistent with the Agreement or (ii) punitive damages or any
other damages not measured by the prevailing party's actual damages, and the
parties expressly waive their right to obtain such damages in arbitration or in
any other forum. In no event, even if any other portion of these provisions is
held to be invalid or unenforceable, shall the arbitrators have power to make an
award or impose a remedy that could not be made or imposed by a court deciding
the matter in the same jurisdiction.

No discovery will be permitted in connection with the arbitration unless it is
expressly authorized by the arbitration panel upon a showing of substantial need
by the party seeking discovery.

All aspects of the arbitration shall be treated as confidential. Neither the
parties nor the arbitrators may disclose the existence, content or results of
the arbitration, except as necessary to comply with legal or regulatory
requirements. Before making any such disclosure, a party shall give written
notice to all other parties and shall afford such parties a reasonable
opportunity to protect their interests.

The result of the arbitration will be binding on the parties, and judgment on
the arbitrators' award may be entered in any court having jurisdiction.