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                                 Exhibit 10.56

                         STRATEGIC ALLIANCE AGREEMENT

       THIS STRATEGIC ALLIANCE AGREEMENT (this "Agreement") is made and entered
                                                ---------
into as of January 8, 2001 by and between ALLSCRIPTS HEALTHCARE SOLUTIONS, INC.,
a Delaware corporation ("Allscripts") and IDX SYSTEMS CORPORATION, a Vermont
                         ----------
corporation ("IDX").
              ---

                              W I T N E S S E T H
                              - - - - - - - - - -

          WHEREAS, Allscripts is in the business of developing and marketing
products and services (the "Allscripts Products") to automate the delivery of
                            -------------------
physician or licensed clinical professional care and associated administrative
tasks using technology at whatever location the physician or licensed clinical
professional performs such activities;

          WHEREAS, IDX has business units that develop and market computer
technology to automate administrative and financial aspects of physician office
medical practice.  Through its subsidiary CHANNELHEALTH INCORPORATED, a Delaware
corporation ("ChannelHealth"), IDX is in the business of developing and
              -------------
marketing products and services (the "Physician Channel Products") to automate
                                       --------------------------
the delivery of physician or allied professional clinical care and associated
administrative tasks carried out by physicians and licensed clinical
professionals using technology at whatever location such physicians or clinical
professionals perform such activities;

          WHEREAS, IDX desires to divest its Physician Channel business and
Allscripts desires to acquire such business;

          WHEREAS, IDX and Allscripts have entered into an Agreement and Plan of
Merger whereby Allscripts will acquire all of the issued and outstanding capital
stock of ChannelHealth, and ChannelHealth will become a wholly-owned subsidiary
of Allscripts (the "Acquisition");
                    -----------

          WHEREAS, IDX and ChannelHealth entered into that certain Cross License
and Software Maintenance Agreement, dated as of January 1, 2000, pertaining to
the use and distribution of certain technology and products (the "Cross License
                                                                  -------------
Agreement"), and, concurrently herewith, the parties are entering into an
---------
Amended and Restated Cross License and Software Maintenance Agreement to modify
the terms and conditions thereof to provide for the transfer of certain
technology to Allscripts (the "License Addendum" and, together with the Cross
                               ----------------
License Agreement, the License Agreement"); and
                       -----------------

          WHEREAS, IDX and Allscripts desire to enter into an exclusive
strategic relationship whereby Allscripts and its Affiliates and successors,
including without limitation, ChannelHealth, and IDX and its Affiliates and
successors, will cooperate in marketing the Allscripts Products and the
Physician Channel Products to IDX customers. Allscripts would agree to sell IDX
products with agreeable revenue sharing or commission arrangement.
<PAGE>

          NOW, THEREFORE, in consideration of the premises, the mutual covenants
and agreements contained herein, and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties agree
as follows:

1.  DEFINITIONS

          Capitalized terms used in this Agreement, unless otherwise defined in
this Agreement, shall have the meanings ascribed to them on Schedule 1 attached
                                                            ----------
hereto.

2.  TERM AND TERMINATION

     2.1  Term.  This Agreement shall be in effect for an initial term of ten
          ----
          (10) years from the date hereof (the "Initial Term") and shall
                                                ------------
          automatically renew for additional, successive two (2) year terms
          unless earlier terminated by either of IDX or Allscripts by giving
          written notice of such party's election not to renew this Agreement
          not later than one (1) year prior to the expiration of the Initial
          Term or six (6) months prior to the expiration of any then current
          successive term.

     2.2  Termination. Notwithstanding the provisions of Section 2.1, this
          -----------
          Agreement may be terminated:

          2.2.1  by Allscripts if IDX shall have defaulted under or breached any
                 material term of this Agreement and shall not have cured such
                 breach within one hundred twenty (120) days after receiving
                 written notice from Allscripts specifying the nature of such
                 default or breach; or

          2.2.2  by IDX if Allscripts shall have defaulted under or breached any
                 material term of this Agreement and shall not have cured such
                 breach within one hundred twenty (120) days after receiving
                 written notice from IDX specifying the nature of such default
                 or breach; or

          2.2.3  by either party upon receipt of a notice from the other party
                 that such other party requires a composition or other similar
                 arrangement with creditors, files for bankruptcy or is declared
                 bankrupt.

     2.3  Effect of Termination; Survival.
          -------------------------------

          2.3.1  In the event that this Agreement is validly terminated as
                 provided herein, then each of the parties shall be relieved of
                 their duties and obligations arising under this Agreement after
                 the date of such termination and such termination shall be
                 without liability to Allscripts or IDX; provided, however, that
                                                         --------  -------
                 the obligations of the parties set forth in Sections 11.7 and
                 11.8 hereof shall survive

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                 any such termination and shall be enforceable hereunder;
                 provided, further, however, that nothing in this Section 2.3
                 --------  -------  -------
                 shall relieve Allscripts or IDX of any liability for a breach
                 of this Agreement.

     2.4  Change of Control.
          -----------------

          2.4.1  Allscripts Change of Control. If a Change of Control of
                 ----------------------------
                 Allscripts or the Physician Channel Products business shall
                 occur at any time during the term of this Agreement whereby a
                 Direct Competitor of IDX shall Control Allscripts or the
                 Physician Channel Products business, (i) IDX shall thereafter,
                 for the term of this Agreement, be entitled to payment of
                 compensation on the sale or license of all Allscripts Products
                 (other than pharmaceutical products) in a percentage amount
                 equivalent to that provided to IDX at the time of such Change
                 of Control pursuant to the Compensation Table set forth in the
                 Development Plan and (ii) immediately at the end of the term of
                 this Agreement, Allscripts shall deliver the source code for
                 all Allscripts Products to IDX.

          2.4.2  IDX or Patient Channel Change of Control. If a Change of
                 ----------------------------------------
                 Control of IDX or the Patient Channel business of IDX shall
                 occur at any time during the term of this Agreement whereby a
                 Direct Competitor of Allscripts shall Control IDX or the
                 Patient Channel business of IDX (i) Allscripts shall
                 thereafter, for the term of this Agreement, be entitled to
                 payment of compensation on the sale or license of all Patient
                 Channel Products in a percentage amount equivalent to that
                 provided to Allscripts at the time of such Change of Control
                 pursuant to the Compensation Table set forth in the Development
                 Plan and (ii) immediately at the end of the term of this
                 Agreement, IDX shall deliver the source code for all Patient
                 Channel Products to Allscripts.

          2.4.3  "Intellectual Property". All rights and licenses granted under
                  ---------------------
                 or pursuant to this Agreement are, and shall otherwise be
                 deemed to be, for purposes of Section 365(n) of the United
                 States Bankruptcy Code (the "Code"), licenses to rights to
                 "intellectual property" as defined in the Code. A party
                 receiving such rights under this Agreement shall retain and may
                 fully exercise all of its rights and elections under the Code.
                 The parties further agree that, in the event of the
                 commencement of bankruptcy proceeding by or against a party
                 under the Code, the other party shall be entitled to retain all
                 of its rights under this Agreement.

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3.  OPERATIONAL MANAGEMENT

          The following obligations shall be in effect during the Initial Term
of this Agreement only:

     3.1  Executive Management. Allscripts and IDX shall each appoint an
          --------------------
          executive with the title of vice president or higher to oversee
          performance under this Agreement. These two executives shall meet not
          less frequently than once each calendar quarter during the Initial
          Term (and more frequently as needed) and shall produce not later than
          five (5) business days after the end of each such calendar quarter a
          written report to the boards of directors of IDX and Allscripts
          setting forth in detail:

          3.1.1  the accomplishments of Allscripts and IDX during the preceding
                 month in performing this Agreement;

          3.1.2  plans for managing the relationship between IDX and Allscripts
                 during the next calendar month;

          3.1.3  any items of dispute or disagreement between IDX and
                 Allscripts;

          3.1.4  plans for resolving any dispute or disagreement between IDX and
                 Allscripts;

          3.1.5  any changes proposed to be made to the Marketing Plan or
                 Development Plan; and

          3.1.6  such other items as may be deemed appropriate by such
                 executives.

4.  PRODUCT DEVELOPMENT

          The following obligations shall be in effect during the Initial Term
of this Agreement only:

     4.1  Product Development.
          -------------------

          4.1.1  Development and Enhancement of Allscripts Products. Allscripts
                 --------------------------------------------------
                 shall be responsible for development of the Physician Channel
                 Products as described in the Development Plan attached hereto
                 as Exhibit A, as such Development Plan is updated from time to
                    ---------
                 time pursuant to Section 4.1.2. IDX shall perform all of its
                 duties under the Development Plan. The parties shall cooperate
                 to jointly test any software used in connection with the
                 Allscripts Products to ensure the functionality of such
                 software prior to distribution thereof to any IDX Customer.

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          4.1.2  Update of Development Plan. IDX and Allscripts shall update the
                 --------------------------
                 Development Plan every calendar quarter during the term of this
                 Agreement unless earlier updated as necessary to maintain the
                 commercial reasonableness thereof. The Development Plan, as
                 updated from time to time, shall describe detailed activities
                 and responsibilities for two-year periods initially commencing
                 on the date hereof. Not later than three (3) months prior to
                 the expiration of the initial two-year term of the Development
                 Plan, and thereafter not later than three (3) months prior to
                 the expiration of each successive two-year period, the parties
                 shall commence work on a revised Development Plan for the
                 following two-year period. The Development Plan, as updated
                 from time to time, shall be executed by the parties and shall
                 become subject to this Agreement. Should the parties have
                 failed to agree upon and execute a revised an updated
                 Development Plan at the time of the expiration of the then
                 current Development Plan, the parties shall continue to perform
                 under the terms of the then current Development Plan until such
                 time as the parties shall agree upon a revised Development
                 Plan. Notwithstanding anything contained herein or in any
                 Development Plan to the contrary, at all times during the
                 Initial Term, Allscripts shall continue to fund the development
                 of the Physician Channel Products as provided in the
                 Development Plan as adopted on the date hereof.

          4.1.3  Participation in Development. Upon reasonable request by the
                 ----------------------------
                 other party, each party agrees to cooperate during the term of
                 this Agreement in the provision of suggestions and
                 specifications for enhancement and improvement of their
                 respective products and services based upon the needs and
                 requirements of their respective customers. If either party
                 agrees to develop additional products, features, functionality,
                 or interfaces, the material terms with respect to such
                 additional development shall be memorialized in a written
                 addendum to this Agreement specifying such terms.

          4.1.4  User Groups. Allscripts shall be given an opportunity to
                 -----------
                 present and participate at IDX's annual ESD and Systems
                 Division national sales and user group conferences.

          4.1.5  Early Releases and Testing. IDX and Allscripts shall deliver to
                 --------------------------
                 each other for testing purposes only, copies of the earliest
                 test releases of all development deliverables provided for in
                 the Development Plan prior to delivery thereof to any other
                 customers or Distribution Partners.

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          4.1.6  Demonstration Products. Each party shall develop demonstration
                 ----------------------
                 versions of its products for use in selling its products to the
                 other party's customers and prospects and shall have access to
                 the demonstration systems of the other party, in accordance
                 with the Demonstration Product Specification.

     4.2  Technologies and Architectures.
          ------------------------------

          4.2.1  Standards.
                 ---------

               4.2.1.1  To facilitate data exchange and ease of use of the
                        parties' respective products, Allscripts Products shall
                        connect with the appropriate technical, architectural,
                        communication, functional design and programming
                        standards embodied in IDX Practice Management Products,
                        as well as the Patient Channel and EDiX products, from
                        time to time, including without limitation the technical
                        standards, protocols, conventions and platforms
                        incorporated in the IDX Web FrameWork. IDX shall provide
                        Allscripts with no less than ninety (90) days' prior
                        written notice before implementing any change with
                        respect to such standards, protocols, conventions or
                        platforms.

               4.2.1.2  IDX represents and warrants, as of the Closing Date,
                        that Physician Channel Products connect with the
                        appropriate technical, architectural, communication,
                        functional design and programming standards embodied in
                        IDX Practice Management Products, as well as the Patient
                        Channel and EDiX products, including without limitation
                        the technical standards, protocols, conventions and
                        platforms incorporated in the IDX Web FrameWork.

               4.2.1.3  To facilitate data exchange between the Patient Channel
                        and the portions of the Allscripts Products related to
                        the Patient Channel, all IDX products shall connect with
                        the appropriate technical, architectural, communication,
                        functional design and programming standards embodied in
                        such Allscripts Products, such compliance to allow for
                        connection with such products. Allscripts shall provide
                        IDX with no less than ninety (90) days' prior written
                        notice before implementing any change with respect to
                        such technical, architectural, communication, design and
                        programming standards embodied in such Allscripts
                        Products from time to time.

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               4.2.2  Databases. Allscripts shall not create the capability in
                      ---------
                      its products and services, or permit the use of its
                      products and services, to write to Practice Management
                      Product database except in conformance with written
                      standards and procedures approved by IDX in advance. IDX
                      shall not create the capability in its products and
                      services, or permit the use of its products and services,
                      to write to any Allscripts Product database except in
                      conformance with written standards and procedures approved
                      by Allscripts in advance. The parties shall regularly keep
                      each other informed of their respective standards and
                      procedures.

          4.3  Data Exchange.
               -------------

               4.3.1  Interfaces. Each of IDX and Allscripts shall develop and
                      ----------
                      maintain Interfaces with respect to each of the products
                      of the other party identified in the Development Plan. The
                      Interfaces, and any updates thereof required to be made to
                      maintain the Interfaces, shall be developed at the
                      complete and sole expense of the developing party with
                      respect to any particular Interface and shall be provided
                      to the other party at no charge. Allscripts shall migrate
                      toward a service oriented architecture in 2002 provided
                      that such architecture is stable, deployable, has
                      comparable performance to currently utilized technologies
                      and has a similar cost structure to currently utilized
                      technologies. Allscripts shall be responsible for
                      integration and support costs related to the guaranteed
                      methods developed by Allscripts in connection with such
                      architecture.

               4.3.2  Synchronization. Each of IDX and Allscripts shall be
                      ---------------
                      required to reasonably maintain the compatibility of their
                      respective products with any updates or new version
                      releases of the products of the other party identified in
                      the Development Plan.

               4.3.3  Additional Interfaces. If the parties agree to develop
                      ---------------------
                      interfaces between their respective products in addition
                      to the Interfaces, the material terms with respect to such
                      additional interfaces shall be memorialized in a written
                      addendum to this Agreement specifying such terms. Upon the
                      execution of such an addendum by each party, such
                      additional interfaces shall be deemed to be Interfaces
                      hereunder.

               4.3.4  Effects on Integration. Each party shall provide ninety
                      ----------------------
                      (90) days' prior notice to the other of any new versions
                      or other material changes in any of its respective
                      products that might affect any Interface. Within a
                      reasonable time following receipt of such notice, the
                      notified party shall make any alterations or updates to

                                       7
<PAGE>

                      any so affected Interface necessary to maintain such
                      Interface, at its own expense.

     4.4  Other Products.  The parties shall make suggestions for developing
          --------------
          functional integration and data exchange among other IDX Practice
          Management Products, EDiX products, Patient Channel Products and
          Allscripts Products for the purpose of creating work flows and
          processes that benefit physicians.

5.  MARKETING OF ALLSCRIPTS PRODUCTS

          The following obligations shall be in effect during the Initial Term
of this Agreement only:

     5.1  Marketing Plan.  During the Initial Term, IDX and Allscripts shall
          --------------
          regularly update a marketing plan for marketing Allscripts Products to
          IDX Customers and prospects, such marketing plan to initially to be
          developed by Allscripts and IDX during the first ninety (90) days
          following the Closing Date (as updated from time to time, the
          "Marketing Plan"). The Marketing Plan shall commence on the Closing
           --------------
          Date, shall include the physician installation targets of new
          physician users of Allscripts Products set forth in Schedule 5.1 and
                                                              ------------
          shall describe detailed activities and responsibilities (including
          without limitation, with respect to implementation) and sales
          forecasts over the initial two-year period of this Agreement, but
          shall be updated not less frequently than every three (3) months. The
          Marketing Plan for the initial two-year period shall be completed and
          executed by the parties no later than ninety (90) days following the
          Closing Date and shall be subject to the terms of this Agreement. Not
          less than three (3) months prior to the expiration of the initial two-
          year period, and thereafter three (3) months prior to the expiration
          of each successive two-year period of the Initial Term, the parties
          shall commence work on a revised Marketing Plan for the following two-
          year sales forecast period. The initial and each revised two-year
          Marketing Plan shall be executed by the parties and shall be subject
          to the terms of this Agreement. Should the parties have failed to
          agree upon and execute a revised Marketing Plan at the time of the
          expiration of the then current Marketing Plan, the parties shall
          continue to perform under the terms of the then current Marketing Plan
          until such time as the parties shall agree upon a revised Marketing
          Plan.

     5.2  Certain Restrictions on Marketing Rights.
          ----------------------------------------

          5.2.1  Restrictions on Allscripts. Except as provided in Section
                 --------------------------
                 5.2.3:

                 5.2.1.1  Allscripts shall not develop any Practice Management
                          Products and shall not enter into any relationship or
                          arrangement with any Direct Competitor of IDX whereby
                          Allscripts or such Direct Competitor of IDX Provides

                                       8
<PAGE>

                        Practice Management Products; provided, that except as
                                                      --------
                        expressly set forth in this Agreement, nothing shall
                        preclude Allscripts from developing or marketing any
                        product, service, or functionality that it currently
                        markets.

               5.2.1.2  Allscripts shall not Provide any products to IDX
                        Customers that are similar to the Virtual Office
                        Products unless IDX has abandoned the marketing of such
                        products.

          5.2.2  Restrictions on IDX. Except as provided in Section 5.2.3, (i)
                 -------------------
                 IDX shall not develop or Provide any products similar to the
                 Allscripts Products and (ii) shall not enter into any
                 relationship or arrangement with any Direct Competitor of
                 Allscripts whereby IDX Provides products similar to or in
                 competition with the Allscripts Products, including without
                 limitation, the IDX products referred to as "OCM" or "Order
                 Communication" or "ESD's Mobile Schedule" (except to continue
                 to market the "ESD Mobile Schedule" as a stand alone
                 application on the Palm Pilot). The Practice Management System
                 of IDX as of the date hereof shall not be deemed to be similar
                 to the Allscripts Products.

          5.2.3  Restrictions Not Applicable. Notwithstanding anything to the
                 ---------------------------
                 contrary contained in this Agreement or in any other agreement
                 between the parties:

               5.2.3.1  Allscripts may cooperatively market Allscripts Products
                        with any vendor of Practice Management Products that is
                        not a Direct Competitor of IDX, to any Person other than
                        IDX Customers.

               5.2.3.2  Allscripts may cooperate with a Person that Provides
                        products and services similar to the Practice Management
                        Products for the purpose of deploying such products and
                        services, on a case-by-case basis to any Allscripts
                        customer or prospect, including without limitation by
                        development of data exchange or interfaces, if such
                        Allscripts customer or prospect requests such similar
                        products or services; provided, that interface
                                              --------
                        development and data exchange performed by Allscripts in
                        connection with such other products or services shall be
                        performed at a charge that is consistent with the
                        ordinary and customary practices of Allscripts, and
                        Allscripts will not cooperate with any Direct Competitor
                        of IDX to provide any financial benefits beyond payment
                        of such ordinary and customary charge.

                                       9
<PAGE>

               5.2.3.3   IDX may Provide any products or services similar to
                         Allscripts Products only as an offering integrated with
                         its LastWord and IDXrad and Imaging Suite product
                         lines, and any other non-Practice Management Product
                         products and services, such as image management. IDX
                         shall not Provide any products or services similar to
                         Allscripts Products as an offering integrated with any
                         Practice Management Products. IDX may Provide any hand-
                         held device for dictation only in connection with its
                         EDiX product line, but not any other products similar
                         to Allscripts Products in connection therewith.

               5.2.3.4  IDX may establish direct connections for pharmacy
                        benefit management companies, drug manufacturers and
                        drug distributors involving a direct message to a
                        patient via the Patient Channel only (except with
                        respect to IDX Customers that utilize LastWord as their
                        inpatient EMR).

               5.2.3.5  IDX may cooperate with a Person that Provides products
                        and services similar to the Allscripts Products for the
                        purpose of deploying such products and services, on a
                        case-by-case basis to any IDX Customer or prospect,
                        using any means, including without limitation,
                        development of interfaces or publication of
                        specifications, if such IDX Customer or prospect
                        requests such similar products or services; provided,
                                                                    --------
                        that interface development and data exchange performed
                        by IDX in connection with such other products or
                        services shall be performed at a charge which is
                        consistent with the ordinary and customary practices of
                        IDX, and IDX will not cooperate with any Direct
                        Competitor of Allscripts to provide any financial
                        benefits beyond payment of such ordinary and customary
                        charge.

               5.2.3.6  Allscripts may market Allscripts Products to any IDX
                        Customer; provided, that Allscripts shall notify IDX of
                                  --------
                        any such marketing efforts within seven (7) days after
                        Allscripts' initial contact with such IDX Customer.

               5.2.3.7  IDX may sell and market CMS subject to the compensation
                        provisions of Section 9.1.
                                      -----------

               5.2.3.8  Clinical Trials. Nothing in this Agreement shall prevent
                        ---------------
                        either party from developing or marketing functionality
                        that that facilitates participation by customers and
                        prospects of such party in clinical trials. With respect
                        to and in connection with marketing such functionality
                        as

                                      10
<PAGE>

                              may be contained in IDX's Practice Management
                              Products, however, IDX shall not resell or
                              distribute products of any Person that are similar
                              to the Allscripts Products.

               5.2.4     Termination of Restrictions. Allscripts may elect to
                         ---------------------------
                         terminate Section 5.2.1 in the event of a Material
                         Adverse Change with respect to IDX, and IDX may elect
                         to terminate Section 5.2.2 in the event of a Material
                         Adverse Change with respect to Allscripts. In the event
                         of a notice given pursuant to this Section 5.2.4 by
                         either party, the notified party may, in its sole and
                         absolute discretion, refer to arbitration pursuant to
                         Section 11.20, the determination of whether the change
                         which is the subject of such notice is a Material
                         Adverse Change.

          5.3  Joint Marketing Duties.
               ----------------------

               5.3.1     Joint Marketing Materials. At their joint expense,
                         -------------------------
                         shared equally, Allscripts and IDX shall develop and
                         produce product marketing documentation and materials
                         similar in kind and quality to that currently provided
                         by Allscripts and IDX to their respective sales
                         prospects for the purpose of promoting and marketing
                         the joint solution for physician office practice,
                         including without limitation, administrative, financial
                         and clinical information systems, through integration
                         of the IDX Practice Management Products and the
                         Allscripts Products.

               5.3.2     User Groups and Trade Shows. Allscripts shall provide
                         ---------------------------
                         for featured participation by IDX at Allscripts' user
                         group meetings involving the Allscripts Products, and
                         IDX shall provide for featured participation by
                         Allscripts at IDX's user group meetings involving the
                         Practice Management Products. Each of Allscripts and
                         IDX shall provide space at their respective user group
                         meetings for the other party's products and shall show
                         such products together with their own respective
                         products. In accordance with the Marketing Plan,
                         Allscripts and IDX shall publicize the alliance created
                         hereby at appropriate trade shows.

               5.3.3     Information Regarding IDX Customers and Competitors.
                         ---------------------------------------------------
                         Allscripts and IDX shall keep each other informed of
                         opportunities that may exist for marketing products to
                         their respective customers. Allscripts shall promptly
                         notify IDX of any sales contact with an IDX Customer.
                         IDX shall provide Allscripts with access to IDX sales
                         pipelines and IDX Customer and competitor databases to
                         the same extent and in the same manner as provided to
                         ChannelHealth prior to the date hereof.

                                       11
<PAGE>

               5.3.4     Joint Sales. Each of Allscripts and IDX shall bill and
                         -----------
                         collect for its own respective products and services
                         provided to IDX Customers. Allscripts and IDX shall
                         each be responsible for the payment to members of their
                         own respective sales forces of any appropriate
                         commissions earned by such members on sales of
                         Allscripts Products pursuant to Sections 5.4 and 5.5.
                         Glen Tullman and Rich Tarrant shall be reasonably
                         available for initial marketing efforts undertaken by
                         Allscripts in connection with the Merger Agreement and
                         for subsequent meetings with customers of the Physician
                         Channel Products (which shall occur no less frequently
                         than once per month).

          5.4  Marketing Duties of Allscripts--Allscripts Products. Allscripts
               ---------------------------------------------------
               shall market the Allscripts Products in accordance with the
               Marketing Plan and in any event shall provide services necessary
               to support IDX's marketing of Allscripts Products to IDX
               Customers as set forth below, at its own expense:

               5.4.1     Allscripts shall continue to develop and produce
                         product marketing documentation and collateral similar
                         in kind and quality to that currently provided by
                         Allscripts to its sales prospects. Allscripts shall
                         deliver such documentation and collateral in reasonable
                         quantities and at such times and places reasonably
                         requested by IDX.

               5.4.2     Allscripts shall provide sales support services with
                         respect to the Allscripts Products as generally and
                         customarily employed by IDX in support of sales of its
                         products, including without limitation, assisting in
                         making sales calls, providing product demonstrations,
                         facilitating site visits and responding to inquiries
                         from prospects and customers, such as requests for
                         proposals, requests for information and requests for
                         quotations.

               5.4.3     Allscripts shall maintain a qualified sales and
                         marketing support staff in numbers reasonably
                         sufficient to support IDX sales activities related to
                         Allscripts Products.

               5.4.4     Allscripts shall provide training to the IDX sales
                         staff in the Allscripts Products and Allscripts'
                         business strategy.

               5.4.5     Allscripts shall provide IDX with current sales
                         projections and regular updates thereto.

               5.4.6     Allscripts shall develop and maintain a program for
                         incenting at least one IDX Customer in each IDX sales
                         region to be a reference site for every Allscripts
                         Product in general release.

                                       12
<PAGE>

               5.4.7     Allscripts shall appropriately compensate and incent
                         its sales personnel to sell Allscripts Products to IDX
                         Customers and prospects.

          5.5  Marketing Duties of IDX--Allscripts Products. IDX shall market
               --------------------------------------------
               the Allscripts Products in accordance with the Marketing Plan and
               in any event shall provide services necessary to support
               Allscripts' marketing of Allscripts Products to IDX Customers as
               set forth below, at its own expense:

               5.5.1     IDX shall educate and train its sales and sales support
                         personnel so as to be able to present the Allscripts
                         Products to IDX Customers and prospects as necessary to
                         appropriately commercialize the Allscripts Products.

               5.5.2     IDX shall appropriately compensate and incent its sales
                         personnel to sell Allscripts Products.

               5.5.3     IDX shall provide Allscripts with current sales
                         projections and regular updates thereto.

               5.5.4     IDX shall include appropriate descriptions of
                         Allscripts Products and Allscripts' business strategy
                         in sales proposals for new business as necessary to
                         appropriately commercialize the Allscripts Products.

               5.5.5     IDX shall respond to requests for information,
                         quotations, proposals and the like for Allscripts
                         Products as necessary to appropriately commercialize
                         the Allscripts Products.

               5.5.6     IDX shall pay reasonable compensation to its sales
                         force for sales of Allscripts Products to IDX
                         Customers; provided, that commission percentages paid
                                    --------
                         on gross profit of Allscripts Products by any member of
                         IDX's sales force shall be not less than commission
                         percentages paid to such members on sales of any other
                         products.

               5.5.7     Quotas for sales of Allscripts Products to IDX
                         Customers and prospects shall be placed on members of
                         IDX's ESD and Systems Division sales force. IDX account
                         executives shall be provided with a special bonus
                         opportunity of $5,000 per year in each of years 2001
                         and 2002 for the achievement of such quotas established
                         pursuant to this Section 5.5.7.

               5.5.8     Each member of IDX's ESD and Systems Division sales
                         management shall be included in bonus plans and
                         commission plans whereby a meaningful portion of such
                         person's annual compensation is based upon overall
                         sales of Allscripts Products.

                                       13
<PAGE>

               5.5.9     IDX shall provide Allscripts employees involved in the
                         sale and development of Physician Channel Products with
                         reasonable access to IDX facilities for the same or
                         similar purposes related to the development, marketing
                         and sale of Physician Channel Products as provided to
                         ChannelHealth prior to the Closing Date.

          5.6  Use of Allscripts Names and Marks. IDX may use the name
               ---------------------------------
               "Allscripts" and the other Allscripts names and marks in
               connection with customer communications pertaining to the co-
               marketing relationship between IDX and Allscripts provided for
               under this Agreement and in accordance with Allscripts'
               reasonable branding standards in effect from time to time.

          5.7  Use of IDX Names and Marks. Allscripts may use the name "IDX" and
               --------------------------
               the other IDX names and marks in connection with customer
               communications pertaining to the co-marketing relationship
               between IDX and Allscripts as provided for under this Agreement
               and in accordance with IDX's reasonable branding standards in
               effect from time to time.

          5.8  Marketing and Administrative Duties of IDX. IDX shall have the
               ------------------------------------------
               authority to market, sell, resell and distribute Allscripts
               Products pursuant to IDX's own terms and conditions as previously
               agreed upon in writing by Allscripts. At IDX's request, IDX and
               Allscripts shall enter into a distribution agreement for the term
               of this Agreement that shall set forth customary terms and
               conditions upon which IDX may purchase, license, sell and
               sublicense the Allscripts Products. To the extent permitted by
               law, IDX shall have authority as Allscripts' agent to bind
               Allscripts to perform for IDX Customers all of Allscripts'
               standard sales terms and conditions as previously agreed upon in
               writing by Allscripts; provided, however, that in the event of a
                                      --------  -------
               failure by an IDX Customer to pay for an Allscripts Product, and
               such failure is not based upon a dispute with respect to such
               Allscripts Product, IDX shall be responsible to Allscripts for
               the sale price of such Allscripts Product. Allscripts shall
               confirm IDX's authority as provided in this Section 5.8 to any
               IDX Customer or prospective customer on request of IDX.

6.   OTHER MARKETING RIGHTS

          6.1  Right to Provide on Non-exclusive Basis. Notwithstanding any
               ---------------------------------------
               termination or non-renewal of this Agreement, other than a
               termination pursuant to Section 2.2.1 and including otherwise
               without limitation any termination under Section 2.2 of this
               Agreement, for so long as Allscripts or any Affiliate of
               Allscripts shall offer, license, support, or maintain any
               Allscripts Products, or any derivatives, enhancements, or
               improvements thereof, IDX shall be entitled to and Allscripts
               shall offer to permit IDX to, Provide such Allscripts Products,
               derivatives, enhancements, and improvements, and support or
               maintenance services with respect thereto, upon the best terms
               and conditions offered by Allscripts or such Affiliate

                                       14
<PAGE>

               of Allscripts to any distributor of Allscripts; provided, that if
                                                               --------
               Allscripts or such Affiliate has no distributor, IDX's provision
               of Allscripts Products shall be upon customary terms and at a
               price equal to Allscripts' direct sale price less a commercially
               reasonable discount.

          6.2  Best Prices. Allscripts or any Affiliate of Allscripts shall at
               -----------
               all times during the term of this Agreement offer IDX Customers
               such prices and terms for Allscripts Products equally favorable
               to the prices (plus any subsidy earned by Allscripts on such
               Allscripts Products) and terms offered to any customer of
               Allscripts similarly situated to such IDX Customer.

7.   TERMINATION OF PRIOR MARKETING OBLIGATIONS

               Upon the Closing, that certain Marketing, Development and Service
Agreement, made and entered into as of January 1, 2000, by and between
ChannelHealth and IDX shall, except for the obligations of the parties set forth
in Section 5.1 thereof, terminate and cease to be of any further effect.

8.   OWNERSHIP

          8.1  In General. Ownership of software developments shall be governed
               ----------
               by the License Agreement, except with respect to Interfaces,
               which shall be governed by Section 8.2 of this Agreement.

          8.2  Interfaces Developed Pursuant to This Agreement. The parties
               -----------------------------------------------
               contemplate that they may individually or jointly develop certain
               new Interfaces. In each instance in which a new Interface is
               created, the parties will agree to a specification for the
               Interface. Where the specification is in the public domain, this
               Agreement does not purport to create any rights for either party
               in such specification. If the specification is owned by one of
               the parties, the other party receives a perpetual, non-exclusive,
               non-transferable license to use the Intellectual Property
               embodied in the Interface specification for the purpose of
               creating the Interfaces contemplated in this Agreement. If a
               specification is jointly authored by the parties, the parties
               shall jointly own such specification and shall be free to use
               such specification without interference from the other party and
               without any obligation to pay any royalties or account for any
               profits. The parties contemplate that Intellectual Property in
               and to the new Interfaces may be created as a result of the
               creation of the new Interfaces. As between the parties, such
               Intellectual Property related to portions of the Interfaces
               intended to (a) organize data from IDX's systems in the manner
               stated in the specification or (b) organize data received in the
               manner stated in the specifications for use by IDX's systems,
               shall be IDX's Intellectual Property. As between the parties, the
               Intellectual Property related to Interfaces intended to (x)
               organize data from Allscripts systems in the manner stated in the
               specification, (y) organize data received in the

                                       15
<PAGE>

               manner stated in the specifications for use by Allscripts'
               systems, or (z) organize data between Allscripts' systems and
               third party systems, shall be Allscripts' Intellectual Property.
               IDX hereby assigns to Allscripts all right, title, and interest
               in and to all Intellectual Property in the new Interfaces that is
               described above as belonging to Allscripts. Allscripts hereby
               assigns to IDX all right, title, and interest in and to all
               Intellectual Property in the new Interfaces that is described
               above as belonging to IDX. The parties agree from time to time to
               exchange and agree upon a written schedule setting forth the
               allocation of the ownership and rights in and to the
               specifications and Intellectual Property used or developed in
               connection with the development of the new Interfaces.

9.   COMPENSATION

          9.1  Compensation; Payment.  IDX and Allscripts shall be entitled to
               ---------------------
               compensation for the sale or license of Allscripts Products and
               IDX products as set forth in the Compensation Table set forth in
               the Development Plan; provided, however, that IDX shall not be
                                     --------  -------
               entitled to any compensation for the sale or license of any
               Allscripts Products or IDX Products installed prior to the
               Closing Date.

          9.2  Minimum Compensation. Provided Allscripts shall not have
               --------------------
               defaulted under or breached any material term of this Agreement
               and shall not have cured such breach within one hundred twenty
               (120) days after receiving written notice from IDX specifying the
               nature of such default or breach:

               9.2.1     If the gross revenues to Allscripts for Allscripts
                         Products (less any commissions paid to IDX by
                         Allscripts and less payments to third parties for
                         equipment sold) for fiscal year 2001 (the "2001
                                                                    ----
                         Revenue") are less than $4.5 million, IDX will pay to
                         -------
                         Allscripts an amount equal to the difference between
                         $4.5 million minus 2001 Revenue.

          9.3  Payments. Any payment to be made by a party pursuant to this
               --------
               Agreement shall be made no later than the twentieth-fifth (25th)
               day of the calendar month next following the calendar month to
               which such payment applies and shall be made by delivery of a
               check, payable to the order of the party entitled to payment or
               by wire transfer of immediately available funds to an account
               designated by such party. Any payment to be made by IDX to
               Allscripts pursuant to Section 9.2 shall be made no later than
               March 31st of the year next following the fiscal year to which
               such payment applies and shall be made by delivery to Allscripts
               of a check, payable to the order of Allscripts or by wire
               transfer of immediately available funds to an account designated
               by Allscripts.

                                       16
<PAGE>

          9.4  Late Fees. Each party agrees to pay late fees equal to one and
               ---------
               one-half percent (1 1/2%) per month on all amounts due but not
               paid within the time provided in Section 9.3.

10.  SERVICES

          10.1 Customer Support Services. Allscripts shall provide customer
               -------------------------
               support services for Allscripts Products, as follows:

               10.1.1    CMS. Allscripts shall provide support for all existing
                         ---
                         CMS customers of IDX in a manner consistent with
                         support provided by IDX to its customers generally and
                         to the level necessary to fulfill all contractual
                         commitments of IDX to its customers for CMS. As the
                         sole compensation to Allscripts for such services, IDX
                         hereby assigns to Allscripts all support fees for CMS
                         it receives from such customers.

               10.1.2    Other Products. At its own expense and cost, Allscripts
                         --------------
                         shall provide Allscripts Maintenance for all IDX
                         Customers of Allscripts Products, including bugs, fixes
                         and drivers, consistent with Allscripts' ordinary and
                         customary business practices. Upgrades to Allscripts
                         Products sold to IDX Customers will be provided in the
                         manner and price as is consistent with Allscripts'
                         ordinary and customary business practices.

               10.1.3    Other Services. Notwithstanding the fact that each
                         --------------
                         party shall be responsible for servicing and supporting
                         its own products, the parties hereby agree to cooperate
                         with respect to installation and implementation of each
                         others' products and in the provision of customer
                         support services. The parties further agree to
                         cooperate to create a seamless help desk, operations
                         support and problem triage model for customers to which
                         products of both parties are marketed and sold. If
                         requested by an IDX Customer, IDX shall be entitled to
                         oversee and coordinate the implementation of such
                         model.

          10.2 Service Quality. All installation services provided by Allscripts
               ---------------
               with respect to sales by IDX of Allscripts Products pursuant to
               Section 5.8 shall be performed in a good and workmanlike manner
               and consistent with standards generally applicable in the
               healthcare clinical information systems industry and consistent
               with the reasonable and customary support standards maintained in
               the healthcare clinical information systems industry or, if
               higher, by the IDX business unit most closely associated with the
               IDX Customer using the Allscripts Products as previously
               communicated to Allscripts in writing. Allscripts employees shall
               be permitted to directly support IDX Customers.

                                       17
<PAGE>

11.  MISCELLANEOUS

          11.1 Confidentiality. Each of IDX and Allscripts will receive or learn
               ---------------
               from, information, both orally and in writing, concerning the
               business of Allscripts or IDX, respectively, including, without
               limitation, financial, technical and marketing information, data,
               and information related to the development of technology and
               services relating to business plans, customers, and markets,
               which information is deemed, in the case of Allscripts,
               proprietary to Allscripts and, in the case of IDX, proprietary to
               IDX. Both parties hereby agree, as set forth below, to protect
               such information, whether furnished before, on or after the date
               of this Agreement, as it protects its own similar confidential
               information, but never less than by commercially reasonable
               efforts, and not to disclose such information to anyone except as
               otherwise provided for in this Agreement. Such information, in
               whole or in part, together with analyses, compilations, programs,
               reports, proposals, studies or any other documentation prepared
               by the parties, as the case may be, which contain or otherwise
               reflect or make reference to such information, is hereinafter
               referred to as "Confidential Information." Each party hereby
               agrees that the Confidential Information will be used solely for
               the purpose of this Agreement and not for any other purpose. Each
               party further agrees that any Confidential Information pertaining
               to the other party is the sole and exclusive property of such
               other party, and that the receiving party shall not have any
               right, title, or interest in or to such Confidential Information
               except as expressly provided in this Agreement. Each party
               further agrees to protect and not to disclose to anyone (except
               as provided in this Agreement) for any reason Confidential
               Information pertaining to the other party; provided, however,
                                                          --------  -------
               that: (a) such Confidential Information may be disclosed to the
               receiving party's respective officers, directors, employees,
               agents, or representatives (collectively, "Representatives") on a
               "need to know" basis for the purpose of this Agreement on the
               condition that (i) each of such Representatives will be informed
               by the receiving party of the confidential nature of such
               Confidential Information and will agree to be bound by the terms
               of this Agreement and not to disclose the Confidential
               Information to any other person and (ii) each party agrees to
               accept full responsibility for any breach of this Section 11.1 by
               its respective Representatives; and (b) Confidential Information
               pertaining to the other party may be disclosed upon the prior
               written consent of the other party. Each party hereby agrees,
               upon the request of the other party, to promptly deliver to the
               other party at the other party's cost the Confidential
               Information pertaining to such other party, without retaining any
               copies thereof. Specifically and without limitation, each party
               agrees to notify the other party promptly in writing upon any
               officer or director learning of any unauthorized disclosure or
               use of the Confidential Information.

                                       18
<PAGE>

          11.2 Non-Confidential Information. The term "Confidential Information"
               ----------------------------
               shall not include any information: (i) which at the time of
               disclosure or thereafter is generally available to or known by
               the public (other than as a result of a disclosure directly or
               indirectly by the receiving party); (ii) is independently
               developed by the receiving party, without reference to or use of,
               the Confidential Information of the other party; (iii) was known
               by the receiving party as of the time of disclosure without a
               breach of confidentiality; (iv) is lawfully learned from a third
               party not under obligation to the disclosing party; or (v) is
               required to be disclosed pursuant to a subpoena, court order or
               other legal process, whereupon the receiving party shall provide
               prompt written notice to the other party prior to such
               disclosure.

          11.3 No-Solicitation. During the first year of the term of this
               ---------------
               Agreement, neither party, nor any Affiliate within its Control,
               shall hire any individual who had been in the employ of the other
               party or any of the other party's Affiliates. After the first
               year of the term of this Agreement, neither party, nor any
               Affiliate within its Control, shall hire any individual who had
               been in the employ of the other party or any of the other party's
               Affiliates until such time as one (1) year has passed since such
               individual was in the employ of the other party.

          11.4 Regulatory Matters. Each party shall adopt, implement, and
               ------------------
               maintain appropriate and compliant policies, procedures, and
               practices necessary to comply with laws and regulations
               (including without limitation the Health Insurance Portability
               and Accountability Act of 1996 ("HIPAA")) applicable to it in its
               business and applicable to it as a business partner of a customer
               of the other to whom products or services are provided under this
               Agreement. The parties agree to amend this Agreement to contain
               any provisions necessary to be included as a result of such
               business partner status. Each party agrees to timely develop and
               include in its respective products covered by this Agreement the
               functionality required to support the minimum necessary standards
               applicable to users of its products as required by HIPAA.

          11.5 No Consequential Damages. In no event shall either party or any
               ------------------------
               Affiliate of either party be liable hereunder for any
               consequential, special, incidental, punitive or indirect damages
               (including without limitation loss of profit, revenue, business
               opportunity or business advantage), whether based upon a claim or
               action of tort, contract, warranty, negligence, strict liability,
               breach of statutory duty, or any other legal theory or cause of
               action, even if advised of the possibility of such damages.

          11.6 Agreements with Healtheon/WebMD. Each of IDX and Allscripts agree
               -------------------------------
               not to cause any default under or termination of (other than a
               termination as a result of a default by Healtheon/WebMD) of the
               contracts between IDX and Healtheon/WebMD and ChannelHealth and
               Healtheon/WebMD.

                                       19
<PAGE>

               In the event IDX shall cause such a default or termination, IDX
               agrees to pay Allscripts such amount of revenues as would have
               been paid to Allscripts under the terms of the defaulted or
               terminated contract if such default or termination by IDX had not
               occurred.

          11.7 Indemnification. Each party (an "Indemnifying Party") will
               ---------------                  ------------------
               indemnify the other party, its officers, employees, and agents
               (each an "Indemnified Party" and, collectively, the "Indemnified
                         -----------------                          -----------
               Parties") against, and hold each Indemnified Party harmless from,
               -------
               all claims, suits, judgments, losses, damages, fines or costs
               (including reasonable legal fees and expenses) ("Losses")
                                                                ------
               resulting from any claim, suit, or demand by any third party
               ("Third Party Claim") for injuries to or deaths of persons or
                 -----------------
               loss of or damage to property arising out of: (i) the
               Indemnifying Party's products or services as marketed by the
               Indemnified Parties, unless the Indemnified Parties shall have
               acted outside the scope of their rights under this Agreement; and
               (ii) the Indemnifying Party's performance or willful misconduct
               of the Indemnifying Party, its employees, officers, or agents in
               connection with the Indemnifying Party's performance of this
               Agreement, except to the extent caused by the negligence of any
               Indemnified Party.

               11.7.1    The Indemnifying Party's obligations under this Section
                         12 will survive the termination of this Agreement.

               11.7.2    Each Indemnified Party shall give an Indemnifying Party
                         prompt written notice of any Third Party Claim of which
                         such Indemnified Party has knowledge concerning any
                         Losses as to which such Indemnified Party may request
                         indemnification hereunder. If the Indemnifying Party
                         acknowledges in writing its obligation to indemnify the
                         Indemnified Party hereunder against any Losses that may
                         result from such Third Party Claim, then the
                         Indemnifying Party shall be entitled to assume and
                         control the defense of such Third Party Claim at its
                         expense and through counsel of its choice if it gives
                         notice of its intention to do so to the Indemnified
                         Party within five (5) days of the receipt of such
                         notice from the Indemnified Party; provided, however,
                                                            --------  -------
                         that if there exists or is reasonably likely to exist a
                         conflict of interest that would make it inappropriate
                         in the judgment of the Indemnified Party, in its sole
                         and absolute discretion, for the same counsel to
                         represent both the Indemnified Party and the
                         Indemnifying Party, then the Indemnified Party shall be
                         entitled to retain its own counsel, at the expense of
                         the Indemnifying Party. In the event the Indemnifying
                         Party exercises the right to undertake any such defense
                         against any such Third Party Claim as provided above,
                         the Indemnified Party shall cooperate with the
                         Indemnifying Party in such defense and make available
                         to the Indemnifying Party, at the Indemnifying Party's
                         expense, all witnesses, pertinent records, materials
                         and information in the

                                       20
<PAGE>

                    Indemnified Party's possession or under the Indemnified
                    Party's control relating thereto as is reasonably required
                    by the Indemnifying Party. Similarly, in the event the
                    Indemnified Party is, directly or indirectly, conducting the
                    defense against any such Third Party Claim, the Indemnifying
                    Party shall cooperate with the Indemnified Party in such
                    defense and make available to the Indemnified Party, at the
                    Indemnified Party's expense, all such witnesses, records,
                    materials and information in the Indemnifying Party's
                    possession or under the Indemnifying Party's control
                    relating thereto as is reasonably required by the
                    Indemnified Party. No such Third Party Claim may be settled
                    by the Indemnifying Party without the prior written consent
                    of the Indemnified Party.

           11.7.3   In no event shall the Indemnifying Party be liable to an
                    Indemnified Party for any indirect, incidental, special,
                    punitive, exemplary or consequential damages arising out of
                    or otherwise relating to this Agreement, even if the
                    Indemnifying Party has been advised of the possibility or
                    likelihood of such damages.

           11.7.4   Notwithstanding the foregoing, with respect to any claim
                    that would otherwise be subject to indemnification by a
                    party pursuant to this Agreement, if indemnification with
                    respect to such claim is governed by the License Agreement,
                    then no indemnification shall be available under this
                    Agreement.

     11.8  Expenses. Except as otherwise specified in this Agreement, all costs
           --------
           and expenses, including, without limitation, fees and disbursements
           of counsel, financial advisors and accountants, incurred in
           connection with this Agreement and the transactions contemplated
           hereby shall be paid by the party incurring such costs and expenses,
           whether or not the Closing shall have occurred.

     11.9  Further Assurances and Documents. IDX and Allscripts shall take all
           --------------------------------
           actions and do all things, including without limitation the execution
           and delivery of instruments and documents, necessary to effectuate
           the purposes and intent of this Agreement.

     11.10 Notices. All notices, requests, claims, demands and other
           -------
           communications hereunder shall be in writing and shall be given or
           made (and shall be deemed to have been duly given or made upon
           receipt) by delivery in person, by courier service, by telecopy or by
           registered or certified mail (postage prepaid, return receipt
           requested) to the respective parties at the following addresses (or
           at such other address for a party as shall be specified in a notice
           given in accordance with this Section 11.10):

                                       21
<PAGE>

                         (a)  if to Allscripts:

                              Allscripts Healthcare Solutions, Inc.
                              2401 Commerce Drive
                              Libertyville, Illinois 60048
                              Attention: President
                              Facsimile: (847) 680-3573

                              With a copy to:

                              Weil, Gotshal & Manges LLP
                              700 Louisiana, Suite 1600
                              Houston, Texas  77002
                              Attention: Steven D. Rubin III
                              Facsimile: (713) 224-9511

                         (b)  if to IDX:

                              IDX Systems Corporation
                              1400 Shelbourne Road
                              South Burlington, VT 05043
                              Attention: President
                              Facsimile: (802) 865-3681

                              With a copy to: General Counsel at the same
                              address

               11.11  Public Announcements. Except as required by law,
                      --------------------
                      governmental regulation or by the requirements of any
                      securities exchange on which the securities of a party
                      hereto are listed, no party to this Agreement shall make,
                      or cause to be made, any press release or public
                      announcement in respect of this Agreement or the
                      transactions contemplated hereby or otherwise communicate
                      with any news media without the prior written consent of
                      the other party, and the parties shall cooperate as to the
                      timing and contents of any such press release or public
                      announcement.

               11.12  Headings. The descriptive headings contained in this
                      --------
                      Agreement are for convenience of reference only and shall
                      not affect in any way the meaning or interpretation of
                      this Agreement.

               11.13  Severability. If any term or other provision of this
                      ------------
                      Agreement is invalid, illegal or incapable of being
                      enforced by any law, governmental regulation or public
                      policy, all other terms and provisions of this Agreement
                      shall nevertheless remain in full force and effect so long
                      as the economic or legal substance of the transactions
                      contemplated hereby is not affected in any manner
                      materially adverse to any party. Upon such determination
                      that any term or other provision is invalid, illegal or
                      incapable of being enforced, the parties hereto shall
                      negotiate in good faith to modify this

                                       22
<PAGE>

                      Agreement so as to effect the original intent of the
                      parties as closely as possible in an acceptable manner in
                      order that the transactions contemplated hereby are
                      consummated as originally contemplated to the greatest
                      extent possible.

               11.14  Entire Agreement. This Agreement, together with the
                      ----------------
                      License Agreement, constitutes the entire agreement of the
                      parties hereto with respect to the subject matter hereof
                      and supersedes all prior agreements and undertakings, both
                      written and oral, with respect to the subject matter
                      hereof.

               11.15  Assignment. This Agreement shall be binding upon the
                      ----------
                      parties and their respective successors, representatives
                      and permitted assigns and their Affiliates Controlled by
                      them, respectively. Neither party may assign this
                      Agreement without the prior written consent of the other
                      party, except that either party hereto may assign its
                      rights hereunder to an Affiliate of such party and either
                      party may, without the consent of the other party, assign
                      and delegate this Agreement and its rights and obligations
                      hereunder in connection with a merger, consolidation or
                      sale of substantially all of its assets (which sale shall
                      include the assignment and assumption of all rights and
                      obligations under the License Agreement); provided,
                                                                --------
                      however, that such assignee or transferee shall assume all
                      -------
                      obligations of the assigning or transferring party and any
                      such assignment shall not relieve the assigning or
                      transferring party of its obligations hereunder.

               11.16  No Third Party Beneficiaries. This Agreement shall be
                      ----------------------------
                      binding upon and inure solely to the benefit of the
                      parties hereto and their permitted assigns and successors
                      and nothing herein, express or implied, is intended to or
                      shall confer upon any other person or entity, any legal or
                      equitable right, benefit or remedy of any nature
                      whatsoever under or by reason of this Agreement.

               11.17  Amendment. This Agreement may not be amended or modified
                      ---------
                      except by an instrument in writing signed by, or on behalf
                      of, each of the parties.

               11.18  Governing Law. This Agreement shall be governed by the
                      -------------
                      laws of the State of Delaware without regard to its
                      conflict of laws provisions.

               11.19  Counterparts. This Agreement may be executed in one or
                      ------------
                      more counterparts, and by the different parties hereto in
                      separate counterparts, each of which when executed shall
                      be deemed to be an original but all of which taken
                      together shall constitute one and the same agreement.

               11.20  Arbitration. The parties shall attempt in good faith to
                      -----------
                      resolve by agreement any claim or controversy arising out
                      of or relating to this Agreement or the breach hereof.

                                       23
<PAGE>

               11.20.1  Subject to the first sentence of this Section 11.20, any
                        and all claims, counterclaims, demands, causes of
                        action, disputes, controversies, and other matters in
                        question arising out of or relating to this Agreement,
                        any provision hereof, the alleged breach of any such
                        provision, or in any way relating to the subject matter
                        of this Agreement or the relationship between the
                        parties created by this Agreement, involving the
                        parties, their Affiliates and/or their respective
                        representatives (all of which are referred to herein as
                        "Arbitrable Claims"), even though some or all of such
                         -----------------
                        Arbitrable Claims allegedly are extra-contractual in
                        nature, whether such Arbitrable Claims sound in
                        contract, tort, or otherwise, at law or in equity, under
                        state or federal law, whether provided by statute or the
                        common law, for damages or any other relief, will be
                        resolved by binding arbitration. Any arbitration will be
                        administered by the arbitrators in accordance with the
                        Commercial Arbitration Rules of the American Arbitration
                        Association (the "AAA") in effect at the time the
                                          ---
                        arbitration is initiated (collectively, the "Rules").
                                                                     -----

               11.20.2  The validity, construction, and interpretation of this
                        agreement to arbitrate, and all procedural aspects of
                        the arbitration conducted pursuant to this agreement to
                        arbitrate, including without limitation, the
                        determination of the issues that are subject to
                        arbitration (i.e., arbitrability), the scope of the
                        arbitrable issues, allegations of "fraud in the
                        inducement" to enter into this Agreement or this
                        arbitration provision, allegations of waiver, laches,
                        delay or other defenses to arbitrability, and the rules
                        governing the conduct of the arbitration (including
                        without limitation, the time for filing an answer, the
                        time for the filing of counterclaims, the times for
                        amending the pleadings, the specificity of the
                        pleadings, the extent and scope of discovery, the
                        issuance of subpoenas, the times for the designation of
                        experts, whether the arbitration is to be stayed pending
                        resolution of related litigation involving third parties
                        not bound by this Agreement, the receipt of evidence,
                        and the like), will be decided by the arbitrators in
                        accordance with the Rules. In deciding the substance of
                        the parties' Arbitrable Claims, the arbitrators shall
                        refer to the substantive laws of the State of Delaware
                        for guidance (excluding Delaware choice-of-law
                        principles that might call for the application of some
                        other state's law). Each party shall be entitled to
                        discovery rights equivalent to those provided under the
                        Federal Rules of Civil Procedure. NOTWITHSTANDING ANY
                        OTHER PROVISION IN THIS AGREEMENT TO THE CONTRARY, THE
                        PARTIES EXPRESSLY AGREE THAT THE ARBITRATORS WILL HAVE
                        ABSOLUTELY NO AUTHORITY TO AWARD CONSEQUENTIAL, TREBLE,

                                       24
<PAGE>

                        EXEMPLARY OR PUNITIVE DAMAGES OF ANY TYPE UNDER ANY
                        CIRCUMSTANCES REGARDLESS OF WHETHER SUCH DAMAGES MAY BE
                        AVAILABLE UNDER DELAWARE LAW, THE LAW OF ANY OTHER
                        STATE, OR FEDERAL LAW, OR UNDER THE FEDERAL ARBITRATION
                        ACT, OR UNDER THE RULES, THE PARTIES HEREBY WAIVING
                        THEIR RIGHT, IF ANY, TO RECOVER CONSEQUENTIAL, TREBLE,
                        EXEMPLARY OR PUNITIVE DAMAGES IN CONNECTION WITH ANY
                        ARBITRABLE CLAIMS.

               11.20.3  The arbitration proceeding will be conducted in New
                        York, New York. Within thirty days of the notice of
                        initiation of the arbitration procedure, the parties
                        shall obtain from the AAA a list of arbitrators from its
                        Commercial Panel from which the parties shall select a
                        panel of three neutral arbitrators in accordance with
                        the Rules and normal procedures of the New York office
                        of the AAA. If necessary, the AAA shall select some or
                        all of the arbitrators when it is authorized to do so
                        under the Rules.

               11.20.4  In the event of an arbitration proceeding between
                        Allscripts and IDX or any of their Affiliates, one half
                        of all fees of the arbitrators will be borne by
                        Allscripts and the other half will be borne by IDX.

               11.20.5  To the fullest extent permitted by law, the arbitration
                        proceeding and the arbitrators' award will be maintained
                        in confidence by the parties.

               11.20.6  The award of the arbitrators will be final and binding
                        on the parties, and judgement thereon may be entered in
                        a court of competent jurisdiction.

       11.21   Waiver of Jury Trial. Each of the parties hereto irrevocably and
               --------------------
               unconditionally waives trial by jury in any legal action or
               proceeding relating to this Agreement or the transactions
               contemplated hereby and for any counterclaim therein.

                                       25
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their respective authorized signatories thereunto duly
authorized as of the day and year first above written.

IDX SYSTEMS CORPORATION                    ALLSCRIPTS HEALTHCARE
                                           SOLUTIONS, INC.


By: /s/ ROBERT W. BAKER, JR.               By: /s/ Glen E. Tullman
                                               ---------------------
-----------------------------------
    [Signature of Authorized Agent]           Glen E. Tullman
                                              Chief Executive Officer

Print Name and Title:

                                       26
<PAGE>

                                  Schedule 1
                                  ----------

                                  DEFINITIONS

          "Affiliate" means, with respect to any specified Person, any other
Person that directly, or indirectly through one or more intermediaries,
Controls, is Controlled by, or is under common Control with, such specified
Person.

          "Allscripts" means Allscripts Healthcare Solutions, Inc. a Delaware
corporation.

          "Allscripts Products" means the products and services (i) offered by
Allscripts as more fully described in the Development Plan, (ii) the Physician
Channel Products as of the Closing Date and (iii) all of the products and
services to be developed as set forth under the Development Plan.

          "Change of Control" means any event, transaction or occurrence as a
result of which either of IDX or Allscripts (i) shall cease to own or control,
directly or indirectly through any of its respective Affiliates, a majority of
the voting rights associated with ownership of its respective voting stock or
(ii) shall cease to have the ability, directly or indirectly, through one or
more of its Affiliates, to elect a majority of its respective board of
directors.

          "ChannelHealth" means ChannelHealth Incorporated, a Delaware
corporation, its successors and assigns, and any other entity which, as of the
Closing, Controls, is Controlled by, or is under common Control with
ChannelHealth.

          "ChannelHealth Customers" means customers that have contracted or are
in the process of contracting for some or all of the products and services
offered by ChannelHealth.

          "Clinical Management Suite" or "CMS" means the product currently
marketed by IDX under the trademark of "CMS" or "Clinical Management Suite,"
including its predecessor product known as "CRS."

          "Closing" means the closing of the acquisition by Allscripts of all of
the issued and outstanding capital stock of ChannelHealth pursuant to the Merger
Agreement.

          "Closing Date" means the date on which the Closing occurs.

          "Compensation Table" means the revenue sharing model as provided in
the Development Plan.

          "ConnectR" means the product currently marketed by IDX under the
trademark "ConnectR."

                                       27
<PAGE>

          "Control" including the terms "Controlling," "Controlled by," and
"under common Control with," means the possession, direct or indirect, of the
power to direct or cause the direction of the management and policies of a
Person, whether through the ownership of voting securities, by contract, or
otherwise.

          "Cross License Agreement" has the meaning set forth in the recitals to
the Strategic Alliance Agreement.

          "Demonstration Product Specification" means the hardware and software
required to demonstrate the Allscripts Products as mutually agreed to in the
Marketing Plan.

          "Development Plan" means the Development Plan as described in Section
4 to the Strategic Alliance Agreement, and as initially set forth on Exhibit A
attached to the Strategic Alliance Agreement.

          "Direct Competitor of Allscripts" means any Person that Provides any
products similar to the Allscripts Products and any successor, assignee,
Affiliate or partner of such Person.

          "Direct Competitor of IDX" means any Person that Provides any Practice
Management Products and is named on Annex A to this Schedule 1 and any
                                    -------
successor, assignee, Affiliate or partner of such Person and any Person that IDX
notifies Allscripts shall be additionally included on Annex A to this Schedule 1
                                                      -------
from time to time.

          "Distribution Partner" means any Person that has the right to market,
cooperatively market, distribute, resell, sublicense, license, sell or otherwise
provide a party's products or services, including by way of example and not in
limitation, any reseller, distributor, licensee, customer, contractor, service
provider, co-marketer, outsourcing vendor, or other information technology
company.

          "EDI" means effecting the exchange of information and transactions
between trading partners over a network using electronic means.

          "IDX" means IDX Information Systems Corporation, a Vermont
corporation.

          "IDX Customer" means any Person that has entered into a written
agreement with IDX pursuant to which IDX provides any of its core products,
including without limitation Practice Management Systems, IDXrad(TM), and
LastWord(R) (the "Core Products"), all Affiliates of such Person, and all
Persons receiving the benefit of any of the Core Products by or through such
Person or Affiliates of such Person including without limitation those IDX
Customers as set forth in the Development Plan.

          "IDX Licensed Technology" means the technology licensed to Allscripts
and ChannelHealth pursuant to the License Addendum.

                                       28
<PAGE>

          "Initial Term" means a period of ten (10) years commencing on the
Closing Date.

          "Intellectual Property" means, without limitation, know-how, trade
secrets, inventions (whether or not patentable), ideas, materials, discoveries,
techniques, plans, designs, formulas, processes, invention disclosures,
technology, data or information, software and documentation therefor, hardware,
source code (including all programmers' notes), procedures, methods, works and
other documentation and information and the right to sue and recover damages for
past, present and future infringement of such intellectual property.

          "Interfaces" means the interfaces between the Allscripts Products and
the IDX Practice Management Products, Patient Channel, and EDiX as described on
Schedule 4.3.1 attached to the Strategic Alliance Agreement.

          "LastWord" means the product marketed by IDX under the trademark
LastWord.

          "License Addendum" has the meaning set forth in recitals to the
Strategic Alliance Agreement.

          "License Agreement" has the meaning set forth in recitals to the
Strategic Alliance Agreement.

          "Maintenance" means the upkeep of software products by a Person
including the provision of bugs, fixes and drivers, consistent with such
Person's ordinary and customary business practices

          "Marketing Plan" has the meaning set forth in Section 5.1 of the
Strategic Alliance Agreement.

          "Material Adverse Change" means any material adverse change in the
business, properties, results of operations, condition (financial or otherwise)
of an applicable Person (other than changes that are the result of economic
factors affecting the economy as a whole or changes that are the result of
factors generally affecting the specific industry or markets in which a party
competes).

          "Merger Agreement" means that certain Agreement and Plan of Merger by
and among Allscripts (formerly named Allscripts Holding, Inc.), Allscripts,
Inc., Bursar Acquisition, Inc., Bursar Acquisition No. 2, Inc., IDX and
Channelhealth, dated as of July 13, 2000, whereby Allscripts agreed to acquire
all of the issued and outstanding capital stock of ChannelHealth.

          "OutReach" means the product currently marketed by IDX under the
trademark "OutReach."

          "Patient Channel" means the product marketed by ChannelHealth and IDX
under the name Patient Channel.

                                       29
<PAGE>

          "Patient Channel Products" means the computer software and
computerized or automated products and services marketed under the name "Patient
Channel" as more fully described in the Development Plan.

          "Person" means any individual, partnership, firm, corporation,
association, trust, limited liability company, limited liability partnership,
unincorporated organization or other entity, as well as any syndicate or group
that would be deemed to be a person under Section 13(d)(3) of the Securities
Exchange Act of 1934, as amended.

          "Physician Channel Products" means the computer software and
computerized or automated products and services marketed under the name
"Physician Channel" as more fully described in the Development Plan.

          "Practice Management Products" means any software application
expressly designed to automate the business processes of physician billing,
physician scheduling and managed care contract administration.

          "Provide" means to market, sell, license, cooperatively market, or
otherwise distribute, including through one or more Distribution Partners.

          "Regulatory Requirements" means all federal and state laws and
regulatory requirements applicable to the use by IDX, IDX Customers,
ChannelHealth, and ChannelHealth Customers of the ChannelHealth products from
time to time during the term of the Strategic Alliance Agreement, including
without limitation those applicable to billing and claims submittal, managed
care, prescriptions, EDI transactions, data transmission, security and privacy,
and program requirements generally applicable to healthcare organizations, such
as those involving accreditation.

          "Strategic Alliance Agreement" means that certain agreement to which
these definitions are a Schedule entitled "Strategic Alliance Agreement" by and
between Allscripts and IDX executed or intended to be executed on the Closing
Date.

          "Virtual Office Products" means the product currently marketed by IDX
under the name "Virtual Office" which allows for secure messaging, managing
appointments, viewing of personal information, monitoring patient account status
and tasking management.

          "Web FrameWork" means the product currently marketed by IDX under the
trademark "IDX Web FrameWork" and as more fully described in the Development
Plan.

                                       30
<PAGE>

                             Annex A to Schedule 1
                             ---------------------

                           Direct Competitors of IDX

Cerner Corporation
Eclipsys Corporation
Epic Systems Corporation
Healtheon/WebMD (except as pursuant to the agreement with ChannelHealth dated
     June 6, 2000)
Infocure
McKesson/HBOC
Medic Corporation
Medical Manager Corporation
Quality Systems
Shared Medical Systems Corporation
Trizetto Corporation

                                       31
<PAGE>

                                 Schedule 5.1
                                 ------------

                        Physician Installation Targets

                                             New Physician Allscripts
                                             ------------------------
                   Year                           Product Users
                   ----                           -------------
                   2001                               5000
                   2002                               7500
                   2003                               7500
                   2004                               7500
                   2005                               7500
                   2006                               7500
                   2007                               7500
                   2008                               7500
                   2009                               4000

                                       32