<PAGE>

                                                                    EXHIBIT 10.2

                  APPLICATION SERVICE PROVIDER (ASP) AGREEMENT
                                     BETWEEN
                           IMPAC MEDICAL SYSTEMS, INC.
                                       AND
                                US ONCOLOGY, INC.


This Application Service Provider (ASP) Agreement ("ASP Agreement") between
IMPAC Medical Systems, Inc. ("IMPAC"), a California corporation, and US
Oncology, Inc. ("US Oncology") is a contract for the license of IMPAC Software
Products, the purchase of ASP Services and the purchase/license of third party
products for use by US Oncology sites on the IMPAC Servers under the following
terms and conditions:

This ASP Agreement is applicable to the US Oncology sites/clusters designated on
Exhibit A attached hereto and incorporated herein and future sites/clusters to
be designated by US Oncology in the form of an amendment to Exhibit A,
collectively referred to as the "US Oncology ASP Sites". In consideration of the
terms and conditions of this ASP Agreement, US Oncology agrees to license
IMPAC's oncology management system software exclusively for Radiation use
throughout the US Oncology network during the term of this ASP Agreement.

1.  IMPAC Software Products, ASP Services, and Pricing:

    A. IMPAC will offer the IMPAC Software Products and the ASP Services, listed
       in Exhibit B attached hereto and incorporated herein, to US Oncology for
       an inclusive fee of *** per US Oncology ASP Site for ***. This pricing is
       valid for US Oncology sites or clusters configured through IMPAC's ASP
       operation in Redwood City, CA.

       1.  All hardware (see Exhibit C attached hereto and incorporated herein),
           software (including necessary third party software), onsite wiring of
           sites, telecommunication and related costs (including: installation
           and training; interface development; and network hardware and
           installation) are inclusive in the *** fee.

       2.  IMPAC agrees that it will hold the prices set forth in Section 1.A.
           above for all new US Oncology ASP Sites for a period of *** from the
           effective date of this ASP Agreement as defined below. IMPAC may
           increase prices for *** of this ASP Agreement for new sites; however,
           such increases shall be ***.

       3.  ***

       4.  The license fees for any additional IMPAC Software Products licensed
           by a US Oncology ASP Site will be amortized over the remaining term
           of the individual US Oncology ASP Site's term.

       5.  IMPAC will provide the IMPAC Software Products and the ASP Service
           provided that US Oncology pays IMPAC in advance the *** fee in effect
           for each US Oncology ASP Site.

    B. The IMPAC Software License and ASP Service Standard Terms & Conditions
       ("Standard Terms & Conditions") attached hereto as Exhibit D and as
       amended in the Addendum attached hereto as Exhibit D Addendum and herein
       incorporated by reference shall be applicable to each License and ASP
       Service Agreement during the respective terms thereof. ***

    C. Additional on-site support after the initial installation is available at
       the then current rates.

    D. A Service Level Agreement is attached hereto as Exhibit E and
       incorporated herein.

    E. ***

    F. Order of Priority In the event of any conflict or inconsistency among the
       terms and conditions set forth in the documents comprising this
       Agreement, the order of priority shall be: 1) this ASP Agreement; 2) the
       Service Level Agreement in the form of Exhibit E; 3) the Addendum to the


*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>

       Standard Terms and Conditions in the form of Exhibit D Addendum; and 4)
       the Standard Terms and Conditions in the form of Exhibit D.

2.  Orders:

    A. IMPAC will schedule a US Oncology ASP Site for the initial installation
       within *** from the receipt of a signed ASP Purchase and License
       Agreement, a signed Purchase Order, the initial *** fee and an initial
       Customer Deposit. *** payments shall be due and payable on ***. The first
       *** payment is due *** following clinical acceptance. The parties agree
       that the first *** fee paid to IMPAC pursuant to this Section 2.A. shall
       be applied to the first *** of the individual US Oncology Site's term.
       Installation of the initial *** shall start no later than ***

    B. The initial Customer Deposit for each US Oncology ASP Site shall be ***,
       which shall not be refundable until the *** of such site's term.
       Thereafter such deposit may be refunded or be applied to the *** for the
       US Oncology ASP Site.

3.  Site Installation

    A. IMPAC will assign a team that is responsible for the implementation and
       training of IMPAC's Software Products and ASP Services at all US Oncology
       ASP sites. IMPAC will provide a dedicated US Oncology implementation
       coordinator. Incremental IMPAC personnel will be assigned as the number
       of US Oncology ASP sites increases.

    B. US Oncology's *** will consist of *** US Oncology sites. Once the *** is
       using the IMPAC software clinically to treat patients using record and
       verify the ***.

       1.  Acceptance of the initial implementation of the *** shall be subject
           to the following: The parties agree that IMPAC shall present a test
           certification for signature to US Oncology which will formally
           document the acceptance and shall represent the objective testing
           results. US Oncology shall sign such documentation acknowledging
           acceptance within *** after first clinical use *** and within *** for
           all subsequent US Oncology ASP Sites. "First clinical use" shall be
           applicable to the initial implementation of each of the IMPAC
           Software Products and the ASP service set forth on the cover page
           applicable to the US Oncology ASP Site. Subsequent licenses of new
           IMPAC Software Products by ***, will be subject to the standard
           Acceptance provision in Section 3.3 of the Standard Terms and
           Conditions. First clinical use is defined as the first use of the
           IMPAC Software Product using live patient data.

       2.  Acceptance as applied to all other US Oncology ASP Sites will be
           subject to Section 3.3 of the Standard Terms and Conditions.

    C. US Oncology will use commercially reasonable efforts to install ***
       US Oncology ASP Sites during the term of this ASP Agreement.

       1.  IMPAC requires that a minimum of *** sites be installed within *** of
           the *** being accepted and going clinical.

       2.  Failure to reach *** in such time frame may result in an increased
           *** fee.

       3.  All existing IMPAC Multi-ACCESS sites that convert from the LAN/WAN
           model to the ASP model will count ***.

       4.  Prior to converting an existing IMPAC Multi-ACCESS site to an ASP
           site, IMPAC and US Oncology will determine what interface work and
           training is needed. Prior to installation, the *** fee for the
           site/cluster will be adjusted to reflect the required level of
           effort.

    D. If the number of installations is not completed during the time period
       established above because of actions attributable to IMPAC, then ***. In
       the alternative, if the number of installations is not completed during
       the time period established above because of actions attributable to US
       Oncology, IMPAC and US Oncology will renegotiate the *** fee.

*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>

    E. The ASP model, as described in Exhibit B, will be implemented for all
       sites at time of the scheduled initial installation, even if MLC and IMRT
       capability are not available at the individual US Oncology ASP Site. Once
       such an installed ASP site acquires such MLC and/or IMRT capability,
       IMPAC will complete the installation of its oncology management system
       ***.

    F. IMPAC will arrange to install the necessary network cabling and hardware
       and to provide support for the entire network (as described in Exhibit C)
       at all existing US Oncology sites that convert to the ASP model as part
       of the *** fee.

       1.  US Oncology will take full responsibility for the installation of the
           network cabling at all newly constructed US Oncology ASP Sites.

       2.  US Oncology agrees that the IMPAC oncology management system will
           reside on its own network with no other applications unless expressly
           approved by IMPAC.

4.  Training:
    A. Initial Training

       1.  Initial installation and training for a US Oncology ASP Site for the
           IMPAC Software Products and the ASP services will consist of *** on
           site during normal business hours on consecutive weekdays by IMPAC
           personnel.

    B. Web-Based Training

       1.  IMPAC will offer quarterly web-based education classes ***. IMPAC
           and US Oncology shall develop a mutually agreed upon calendar and
           curriculum for such classes.

    C. Custom Training at IMPAC

       1.  IMPAC agrees that during the term of the ASP Agreement it will
           provide US Oncology with a custom training class on specific IMPAC
           Software Products as agreed by the parties to take place at either
           IMPAC's Mountain View, CA, Henderson, NV or Cambridge, MA office on a
           mutually agreed upon date, with at least *** advance notice, for ***
           US Oncology staff members for *** during normal business hours. US
           Oncology shall be responsible for the cost of transportation,
           lodging, meals and/or other expenses of its staff incurred in
           attending the custom training class.

    D. Custom Training at US Oncology

       1.  IMPAC agrees that during the term of the ASP Agreement it will
           provide US Oncology with a custom training class on specific IMPAC
           Software Products as agreed by the parties to take place at a US
           Oncology site for *** during normal business hours, with *** advance
           notice. IMPAC and US Oncology shall develop a mutually agreed upon
           date, time and curriculum for such custom training class.

    E. Additional On-Site Support

       1.  Additional on-site support after the initial installation is
           available at the then current rates.

5.  Strategic Program Management:

    A. IMPAC agrees to meet *** with the US Oncology Radiation Service Directors
       in order to discuss outstanding IMPAC Software Product and ASP service
       issues, IMPAC Software Product development, and any other topics of
       interest relevant to US Oncology's relationship with IMPAC. ***. Each
       organization shall be responsible for the cost of transportation,
       lodging, meals and/or other expenses of its staff incurred in attending
       the meetings.

    B. IMPAC agrees that its Vice President of Sales and National Accounts
       Manager shall meet with US Oncology Management *** at the US Oncology
       Corporate Offices in Houston, TX to review business plans and assess
       progress towards US Oncology's oncology management information system
       goals.

*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
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<PAGE>

    C. IMPAC Client Services agrees to coordinate *** implementation status
       conference with US Oncology in order to review the status of
       sites/clusters currently in the implementation process and those planned
       to begin implementation in the near future.

6.  Third Party Manufacturer's Interface Pricing

    A. Required third party manufacturer's interfaces for linear accelerators
       and simulators may be purchased either through IMPAC or from the
       manufacturer directly. A 100% deposit for such interfaces shall be due
       with the signed License and ASP Service Agreement. IMPAC's current fees
       for these interfaces follows, any increases in price will be passed on to
       US Oncology:

       1.  Varian EXCI Factory Installed (EX Series)            $***
       2.  Varian EXCI Field Installed (EX Series)              $***
       3.  Varian CSSI Factory Installed (C-Series)             $***
       4.  Varian CSSI Field Installed (C-Series)               $***
       5.  Varian CCX Field Installed (Non-C-Series)            $***
       6.  Varian ECI Factory Installed (Ximatron)              $***
       7.  Varian ECI Field Installed (Ximatron)                $***

7.  Term:  This ASP Agreement expires five (5) years from the date first signed
    below ("Effective Date").

    A. Each US Oncology ASP Site will have a *** term from the date of
       commencement of the ASP Service to the individual site.

    B. During *** of this ASP Agreement, IMPAC and US Oncology shall negotiate
       the terms for years 6 and beyond. The following options will be
       available:

       1.  If a cluster of sites decides to remain on the ASP Service then they
           will continue to pay a mutually agreed upon *** fee that will include
           the services listed on Exhibit B and a *** fee for the IMPAC
           Software.

       2.  If a US Oncology site or cluster of sites decides to transfer their
           database from the ASP model to a LAN/WAN model then there will be
           fees for the transfer of the database, the file server and software
           installation, and reconfiguration of the network. Additional training
           will be available at the then current prices.

8.  Hardware Support

    A. IMPAC will remotely trouble shoot US Oncology ASP Site hardware (limited
       to hardware listed in Exhibit C) problems through IMPAC's Client Services
       Support Desk with assistance from the individual US Oncology ASP Site to
       determine the origin of the problem.

       1.  If the problem is determined to be software related, IMPAC will
           undertake its obligations under Section 5.1.1. of the Standard Terms
           & Conditions.

       2.  If the problem is determined to be with the hardware and can not be
           repaired remotely, then

          a.   IMPAC will ship a replacement to the site within ***, standard
               shipping, *** to the US Oncology ASP Site.

                   i.In the event that the defective hardware is the PC attached
                     to the linac, IMPAC will have an alternate PC, *** ready to
                     replace the defective hardware.***. IMPAC will ship a
                     replacement for the alternate PC within ***.

           b.  the US Oncology ASP Site agrees to package and ship the
               non-working hardware to the IMPAC Mountain View campus within
               ***.

       3.  IMPAC reserves the right to deliver repaired and/or equivalent
           hardware as replacements for defective hardware.

       4.  In the event that IMPAC determines that an on-site visit is required
           in order to support the US Oncology ASP Site hardware, *** will be
           charged. IMPAC reserves the right to

*** Certain information on this page has been omitted and filed separately with
    the Commission. onfidential treatment has been requested with respect to the
    omitted portions.

<PAGE>

           designate a third party to handle any on-site hardware support issue.
           IMPAC further reserves the right to charge *** for the on-site visit
           if IMPAC determines that the hardware problem occurred as a result of
           gross negligence or willful misconduct on the part of US Oncology
           personnel.

9.  Software Maintenance/Upgrade

    A. IMPAC agrees that at time of the initial installation of the IMPAC
       Products, each US Oncology ASP site will receive the most current
       production version of the IMPAC Products set forth on Exhibit B. IMPAC
       shall provide each US Oncology ASP cluster with upgrades of new releases
       for the IMPAC Products as long as such cluster's *** fees are paid
       current. Upgrades of the licensed IMPAC Products on the IMPAC servers
       will be coordinated with the appointed representative for the respective
       US Oncology ASP site/cluster.

    B. Multi-ACCESS Help is updated with every release. Additionally, release
       notes are distributed to describe new features and enhancements specific
       to that release. Upon coordination of the software updates, IMPAC agrees
       to provide each US Oncology ASP site an IMPAC software "Release Note"
       detailing the new features and enhancements specific to that release.

Accepted at Mountain View, California:

US Oncology, Inc.                                 IMPAC Medical Systems, Inc.

BY: /s/ William Herman                            BY: /s/ Joseph K. Jachinowski
    ---------------------------------                 --------------------------
      William Herman                                  Joseph K. Jachinowski
TITLE: VP & GM Cancer Center Svcs.                    President & CEO
       ---------------------------
DATE: 5/31/02                                     DATE: 6/3/02
      -----------------                                 ---------------



*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>

Exhibit A                       US Oncology Sites

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
     AZ            CO             Portland         ugene           WA               OK                    NY               NV
------------------------------------------------------------------------------------------------------------------------------------
<S>           <C>               <C>              <C>             <C>           <C>                       <C>        <C>
Craycroft     Aurora            NCS Vancouver    Williamette     N Spokane     Stillwater               Amsterdam        NROC East
                                                                                                                          (Twain)
Green Valley  Colorado Springs  Rose Quarter                     S Spokane     Oklahoma City Hefner     Latham           NROC Main
Northwest     Englewood                                                        McAlester                Rexford          NROC Siena
St. Mary's    Thornton                                                         Tulsa                    Hudson           NROC West
Yuma
------------------------------------------------------------------------------------------------------------------------------------

<CAPTION>

------------------------------------------------------------------------------------------------------------------------------------
          TOPA                       IL               IN                  OH                      KS             MN          MO
------------------------------------------------------------------------------------------------------------------------------------
<S>          <C>                <C>              <C>                 <C>                         <C>           <C>        <C>
Sammons      Plano              Niles            S Indy               S Dayton                   Overland Park Maplewood  Columbia
Dallas SW    Sherman            Melrose Park     Hancock                                                                  Kirksville
                                ----------------------------------------------------------------------------------------------------
Mesquite     Tyler
                                -------------------------------------------------------------------------------
Austin South Palestine               TX               FL                  MD                      SC
                                -------------------------------------------------------------------------------
Brownsville  Arlington          San Marcos       FCC Brooksville      Carroll County Westminster Andrews
Harlingen    Edwards            New Braunfels    FCC New Port Richey                             Eastside
McAllen      Klabzuba           North Austin     FCC Cancer Institute                            Seneca
Waco         Abilene            Austin Northwest FCC Brandon                                     GHS
Balcones     Denton             ACC MLK          FCC St. Petersburg
Beaumont     El Paso East                        FCC Sun City
Deke Slayton El Paso West                        FCC Zephyrhills
Medical City Lewisville                          FCC Hyde Park
Denison      Midland                             Ft. Lauderdale
Longview     Odessa                              Orlando
Paris        Wichita Falls                       Jacksonville
</TABLE>

<PAGE>

Exhibit B
                               US Oncology, Inc.
                         IMPAC Software Product Package

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IMPAC Software Products Included:             ***          ***             ***
                                              ---          ---             ---
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   ---------------------------------------------------------------

   Non IMPAC Products Included with Base System
   ---------------------------------------------------------------
                             ***
   ---------------------------------------------------------------
                             ***
   ---------------------------------------------------------------
                             ***
   ---------------------------------------------------------------
                             ***
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                             ***
   ---------------------------------------------------------------


   ***Certain information on this page has been omitted and filed separately
   with the Commission. Confidential treatment has been requested with respect
   to the omitted portions.

<PAGE>

Exhibit C                   Hardware Product Package

                                      IMPAC
                                  ASP Hardware
                         Base System with View Station*

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------
                 2/15/2002 Submission
--------------------------------------------------------------------------------------------
                                                              Part #               Qnty
--------------------------------------------------------------------------------------------
<S>                                                  <C>                            <C>
Compaq Evo D500                                             470023-301              ***
--------------------------------------------------------------------------------------------
NEC Accsync 90 19" Monitor                                    AS -90                ***
--------------------------------------------------------------------------------------------
NEC Accusync 120 21" Monitor                                  AS -120               ***
--------------------------------------------------------------------------------------------
Compaq 128MB Module                                         174224-B21              ***
--------------------------------------------------------------------------------------------
HP Laser Jet 4100n printer                                  C8050A#ABA              ***
--------------------------------------------------------------------------------------------
KVM Micro Extender CAT5 Dual Access                   Keyboard/Mouse Extender       ***
--------------------------------------------------------------------------------------------
100' CAT5 Solid Conductor Cable PVC                       100' KVM Cable            ***
--------------------------------------------------------------------------------------------
Keyboard                                                  IBM Compatible            ***
--------------------------------------------------------------------------------------------
Mouse                                                    Logitech MouseMan          ***
--------------------------------------------------------------------------------------------
Digital Camera                                           Sony Mavica FD87           ***
--------------------------------------------------------------------------------------------
Zebra LP2824 Parallel Label Printer                       2824-20200-0001           ***
--------------------------------------------------------------------------------------------
Additional Labels                                        2 Rolls per pack           ***
--------------------------------------------------------------------------------------------
MS9540 Voyager w/Codegate, KBW Cables                     MS9540 Voyager            ***
--------------------------------------------------------------------------------------------
CISCO Catalyst 2950 24-port Switch                            298050                ***
--------------------------------------------------------------------------------------------
Packet Shaper 2500- 10MB Unit                              PS2500-L010M             ***
--------------------------------------------------------------------------------------------
Packet Shaper 2500- 2MB Unit                               PS2500-L002M             ***
--------------------------------------------------------------------------------------------
Belkin CAT5e RJ-45M to RJ-45M Patch 7' cable yellow        A3L791-07-YLW            ***
--------------------------------------------------------------------------------------------
</TABLE>

*          ***

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portion.

<PAGE>

Exhibit D Addendum

                   SOFTWARE LICENSE AND ASP SERVICES STANDARD
                          TERMS AND CONDITIONS ADDENDUM
                                     BETWEEN
                           IMPAC MEDICAL SYSTEMS, INC.
                                       AND
                                US ONCOLOGY, INC.

This Addendum supplements and is part of the Application Service Provider (ASP)
Agreement, between IMPAC Medical Systems, Inc. ("IMPAC") and US Oncology, Inc.
("Customer"), and includes modifications to IMPAC's Software License and ASP
Services Terms & Conditions, Document Number USO/ASP (4/02), as follows:

2.1.1. Grant of License Add a new fourth sentence to read: Internal use means
use by Customer including Customer's subsidiaries and affiliated physician
practices and their employees or contractors.

2.1.2. Authorized Use Modify the second sentence to read: Customer will take
commercially reasonable steps to protect the security and confidentiality of all
data, information, programs, systems, materials, techniques, and procedures
which are delivered to Customer by IMPAC.

2.1.6. Limited Warranty Modify the second sentence to read: If any IMPAC Product
or ASP Service fails to so perform during such ninety (90) day period, Customer
shall promptly notify IMPAC of, and shall adequately describe, any such failure
encountered by Customer and IMPAC's sole obligation, with respect to IMPAC
products and Customer's exclusive remedy, with respect to IMPAC Products shall
be to take corrective action as specified in Section 5.1 at no charge to
Customer.

2.1.7. DISCLAIMER OF WARRANTY  Modify the beginning of this section to read:
EXCEPT AS EXPRESSLY PROVIDED FOR IN SECTION 2.1.6 OR EXHIBIT E OF THE
APPLICATION SERVICE PROVIDER (ASP) AGREEMENT,

2.2.   Purchase and License of Other Products

2.2.1. Modify the second sentence to read: The purchase and license of such
Other Products (as listed in Exhibit B of the ASP Agreement) shall be subject to
IMPAC's obligations for support under Section 8 of the ASP agreement and subject
to and in accordance with the standard terms and conditions of purchase and
license under the standard agreements of the Third Party Suppliers.

3.3.   Acceptance Modify this section to read: The parties agree that IMPAC
shall present a test certification for signature to US Oncology which will
formally document the acceptance of the IMPAC Product and ASP Service and shall
represent the objective testing results. US Oncology shall sign such
documentation acknowledging acceptance within *** after first clinical use.
"First clinical use" shall be applicable to the initial implementation of each
of the IMPAC Software Products and the ASP service set forth on the cover page
applicable to the US Oncology ASP Site. First clinical use is defined as the
first use of the IMPAC Software Product using live patient data. In the event
that there is damage to, errors in or shortages in the IMPAC Products, Customer
shall notify IMPAC in writing within such *** period.

*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>

Exhibit D Addendum

4.1.   Fees  Modify the first sentence to read:  All license, setup and
hosting fees for the IMPAC Products shall be payable as set forth in Section 1
of the ASP Agreement.

4.2.   Taxes and Other Charges Modify the second sentence to read: Customer
shall be responsible for payment of all such taxes or charges except for any
taxes based solely on IMPAC's net income or capital.

5.1.1. Maintenance and Support Services for IMPAC Products Modify subsections
(iii) and (iv) to read: (iii) maintain a support desk for receipt of ***
Customer telephone calls for first level diagnosis of IMPAC Product problems
during the hours of *** Pacific time, Monday through Friday, IMPAC holidays
excepted,; (iv) provide emergency beeper service during the hours of ***
Pacific time during IMPAC holidays, and ***; and

5.1.4. Limitations on IMPAC's Obligations  Add the following to the end of
this section:

Notwithstanding the foregoing, IMPAC agrees that if *** that is contained in the
IMPAC Products as of the date of Acceptance is ***, then IMPAC shall provide
Customer with ***. The preceding sentence shall apply only if Customer has paid
the ASP fee, ***, without interruption during the term of this Agreement.

5.2.   Maintenance and Support by Third Party Suppliers Modify the first
sentence and add a new second sentence to read: Maintenance and support of the
Other Products by Third Party Suppliers shall not be provided by IMPAC and shall
be provided in accordance with the terms and conditions of such Third Party
Suppliers' standard agreements as assigned to Customer pursuant to Section 2.2
above. Notwithstanding the foregoing, maintenance and support of the Products
listed in Exhibit C to the ASP Agreement shall be provided by IMPAC in
accordance with the terms and conditions as set forth in Section 8 of the ASP
Agreement, and shall be provided in accordance with the terms and conditions of
such Third Party Suppliers' standard agreements as assigned to Customer pursuant
to Section 2.2 above.

8.     Modification of Product by Customer Add a new third sentence to read:
Notwithstanding the foregoing, Customer has the right to stay at the last prior
major release of the IMPAC Products at all times, if the improvement or update
to the IMPAC Products or the Other Products is not required for such last major
release then the preceding sentence shall have no effect on IMPAC's maintenance
and support obligations hereunder.

Accepted at Mountain View, California:

US Oncology, Inc.                           IMPAC Medical Systems, Inc.

BY: /s/ William Herman                      BY: /s/ Joseph K. Jachinowski
    -----------------------------------         ------------------------------
    William Herman                              Joseph K. Jachinowski
TITLE: VP & GM Cancer Center Svcs.              President & CEO
       ---------------------------
DATE: 5/31/02                               DATE: 6/3/02
      ----------------                            -----------------


*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>

Exhibit D


SOFTWARE LICENSE AND ASP SERVICE STANDARD TERMS AND CONDITIONS

1.   Definitions
1.1. Agreement This Agreement consists of these Software License
and ASP Service Standard Terms and Conditions, any attachments and the cover
page hereto.
1.2. Documentation The term "Documentation" means the specifications and other
documentation relating to the use and performance of a Product, that may be
provided by IMPAC, in effect at the time such Product is licensed by Customer.
1.3. ASP Services The term "ASP Services" means the act of installing,
configuring, maintaining and transmitting the IMPAC Product through IMPAC
Servers at IMPAC's data center.
1.4. IMPAC Products The term "IMPAC Products" means IMPAC's proprietary computer
software programs identified on the cover page and all related materials and
documentation received by Customer from IMPAC.
1.5. IMPAC Server The term "IMPAC Server" means the physical machines where the
IMPAC Product and Customer data will be hosted and maintained by IMPAC. 1.6.
Other Products The term "Other Products" means the hardware products, software
products, and services of Third Party Suppliers identified on the cover page and
all related materials and documentation received by Customer from IMPAC or such
Third Party Supplier. 1.7. Products The term "Products" means collectively the
IMPAC Products and Other Products delivered to Customer under this Agreement.
1.8. Third Party Supplier The term "Third Party Supplier" means the supplier(s)
identified for the Other Products on the cover page.

2.   Purchase and License
2.1. License to IMPAC Products 2.1.1. Grant of License Subject to the
provisions of this Agreement, IMPAC hereby grants to Customer, and Customer
hereby accepts from IMPAC, a nonexclusive, nontransferable, nonassignable
limited license to use the IMPAC Product hosted on the IMPAC Server for internal
purposes only in accordance with this Agreement during the term of this
Agreement. Customer acknowledges and agrees that the IMPAC Product is the
proprietary information and a trade secret of IMPAC and that this Agreement
grants Customer no title or rights of ownership in the IMPAC Product. Customer
agrees not to market, sublicense, distribute, permit timeshare, or allow any
other access to the IMPAC Product other than Customer's own internal use as
permitted hereby. The data files and patient data stored on the IMPAC Server are
and shall remain the exclusive property of Customer.
     2.1.2. Authorized Use Customer is authorized to use the IMPAC Product only
through the IMPAC Server via the method specified in the current Documentation.
Customer agrees that it will not use or permit the IMPAC Product to be used in
any manner, whether directly or indirectly, that would enable Customer's
customers, employees, or any other person or entity to use the IMPAC Product
other than through the IMPAC Servers. Customer will take all necessary steps to
protect the security and confidentiality of all data, information, programs,
systems, materials, techniques, and procedures which are delivered to Customer
by IMPAC.
     2.1.3. Deliverables IMPAC shall provide Customer access to the IMPAC
Product in machine readable object code form, training materials and the on-line
help system for the IMPAC Product.
     2.1.4. Proprietary Markings Customer agrees not to remove or destroy any
proprietary or copyright markings or confidential legends placed upon or
contained within the IMPAC Product or any related material and documentation.
     2.1.5. Restrictions on Use Customer agrees that while this Agreement is
in effect, or while Customer has custody or possession of any property of IMPAC,
Customer will not; (i) copy or duplicate, or permit anyone else to copy or
duplicate, any physical, magnetic, or other version of the IMPAC Product,
documentation or information furnished by IMPAC in machine-readable form; (ii)
create or

        IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View,
                      CA 94041 T/800.623.8800 F/650.6238911
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Exhibit D



attempt to create, reverse engineer or otherwise, the source programs or any
part thereof from the IMPAC Product or from other information made available
under this Agreement or otherwise (whether oral, written, tangible, or
intangible); (iii) modify the Products in any manner without the express written
authorization of IMPAC or the appropriate Third Party Supplier, as the case may
be. Customer may copy for its own use and at its own expense training materials
and other terminal-user-oriented materials. All such copies shall contain
IMPAC's copyright notice and ownership declaration.
     2.1.6. Limited Warranty IMPAC warrants that it will use commercially
reasonable efforts to provide the ASP Services uninterrupted and that each IMPAC
Product, installed on IMPAC Servers, will perform substantially as described in
its current Documentation for (90) days from actual network activation date. If
any IMPAC Product or ASP Service fails to so perform during such ninety (90) day
period, Customer shall promptly notify IMPAC of, and shall adequately describe,
any such failure encountered by Customer and IMPAC's sole obligation, and
Customer's exclusive remedy, shall be to take corrective action as specified in
Section 5.1 at no charge to Customer. IMPAC does not warrant that any IMPAC
Product is error-free or that its use will be uninterrupted. IMPAC shall not be
obligated to remedy any IMPAC Product defect, which cannot be adequately
repeated. The warranties in this Section 2.1.6 do not apply to any IMPAC Product
which has been; (i) altered, except by IMPAC or in accordance with IMPAC's
written instructions; (ii) used in conjunction with any product other than those
approved by IMPAC; or (iii) damaged by improper electrical power or environment,
abuse, misuse, accident or negligence.
     2.1.7. DISCLAIMER OF WARRANTY EXCEPT AS EXPRESSLY PROVIDED IN SECTION
2.1.6, THE IMPAC PRODUCT IS PROVIDED "AS-IS" AND ANY FAILURE BY IMPAC TO PROVIDE
THE ASP SERVICES ARE WITHOUT ANY OTHER WARRANTY WHATSOEVER. IMPAC DISCLAIMS ALL
OTHER WARRANTIES WITH REGARDS TO THE IMPAC PRODUCT INCLUDING WITHOUT LIMITATION
ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT, AND ALL OBLIGATIONS OR LIABILITIES ON THE PART OF IMPAC FOR
DAMAGES, INCLUDING BUT NOT LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES
ARISING OUT OF, OR IN CONJUNCTION WITH, THE USE OR PERFORMANCE OF THE IMPAC
PRODUCT.
     2.1.8. Term The license granted under this Section 2.1 shall begin upon
commencement of the ASP Service to the Customer, provided, however, the ASP
Service shall not commence unless and until IMPAC receives a signed License and
ASP Service Agreement and Purchase Order from Customer, plus the payment
specified as Due With Order set forth on the cover page hereto. The initial term
of this Agreement shall continue for the time period specified on the cover page
hereto unless sooner terminated by IMPAC in accordance with the provisions of
this Agreement. Thereafter, the term of the license granted to and the ASP
Services for Customer shall automatically renew for subsequent one (1) year
periods and IMPAC's then current renewal fees shall be due hereunder, unless
either party provides written notice of termination at least ninety (90) days
prior to the expiration of the initial term or the anniversary date of a renewal
term, subject to IMPAC's right to terminate due to Customer's breach of its
obligations under this Agreement.
2.2. Purchase and License of Other Products
     2.2.1. IMPAC will facilitate the purchase and license of the Other Products
on behalf of Customer. The purchase and license of such Other Products shall be
subject to and in accordance with the standard terms and conditions of purchase
and license under the standard agreements of the Third Party Suppliers. Customer
agrees to execute and deliver to IMPAC all agreements required to be executed by
Third Party Suppliers. Customer acknowledges that IMPAC is not authorized to
modify, amend, or supplement, and has not modified, amended, or supplemented,
any term or condition of any Third Party Supplier's standard agreement. IMPAC
assigns, to the maximum extent permitted by applicable law and applicable
contracts, any and all warranties, maintenance and support obligations, or other
benefits supplied by a Third Party Supplier under its standard agreement to
Customer, and authorizes and appoints Customer to enforce, in its name and at
its own expense, any warranty, maintenance or support obligation, or other
benefit which may be made against the Third Party Supplier, but IMPAC assumes no
obligation

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
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Exhibit D



as to the extent or enforceability thereof.
     2.2.2. DISCLAIMER CUSTOMER ACKNOWLEDGES AND AGREES THAT IMPAC IS NOT THE
MANUFACTURER OR SUPPLIER OF THE OTHER PRODUCTS SUPPLIED BY THIRD PARTY SUPPLIERS
AND IMPAC ASSUMES NO RESPONSIBILITY FOR THE PERFORMANCE OR USE OF SUCH PRODUCTS.
IMPAC, NOT BEING THE MANUFACTURER OR SUPPLIER OF THE OTHER PRODUCTS, HAS NOT
MADE AND DOES NOT MAKE ANY REPRESENTATION, WARRANTY OR COVENANT, EXPRESSED OR
IMPLIED WITH RESPECT TO THE DESIGN, CONDITION, DURABILITY, SUITABILITY,
NON-INFRINGEMENT, FITNESS FOR USE OR MERCHANTABILITY OF OTHER PRODUCTS IN ANY
RESPECT. AS BETWEEN IMPAC AND CUSTOMER, THE OTHER PRODUCTS SHALL BE ACCEPTED AND
PURCHASED OR LICENSED BY CUSTOMER "AS-IS" AND WITHOUT WARRANTY BY IMPAC.
CUSTOMER AGREES TO SETTLE ALL CLAIMS DIRECTLY WITH THE APPROPRIATE THIRD PARTY
SUPPLIER AND WILL NOT ASSERT ANY SUCH CLAIMS AGAINST IMPAC.

2.3. ASP Services
     2.3.1. ASP Service IMPAC shall make available hard disk space which shall
be accessible by means of a dedicated network that shall be available for access
by Customer at any time, except such times that the service of IMPAC is
inaccessible due to equipment malfunction, upgrade activities, system backup
activities or any other related maintenance procedures which IMPAC shall be
required to complete from time to time. In the event of a scheduled system
maintenance that requires system downtime, IMPAC shall give reasonable advance
notice to all Customers affected. Scheduled down-time shall not occur during the
hours of 3:00 a.m. to 9:00 p.m. Pacific time, Monday through Friday. IMPAC shall
make reasonable efforts to perform such voluntary maintenance activities at
times of lowest system usage.
     2.3.2. Hard Disk Space Customer shall be allotted sufficient storage
space on the IMPAC Servers to support the application and to store Customer's
databases.
     2.3.3. Customer Database IMPAC shall store Customer's database on the IMPAC
Servers. The parties expressly recognize that the dedicated network equipment
and telecommunications links are susceptible to crashes and down time. IMPAC
shall use its best efforts to maintain a consistent link with the dedicated
network, but cannot and does not warrant that it shall maintain a continuous and
uninterrupted link.
     2.3.4. Database Backup IMPAC shall maintain working backup copies of
Customer's database. The IMPAC backup copy is only to be accessible by IMPAC in
the event of maintenance, crashes, downtime and service interruptions. IMPAC
will make at least one working backup copy of its files - with one copy
remaining off-site, or in a different location than the first copy.
     2.3.5. Maintenance IMPAC may, at its own discretion, temporarily
suspend all service for the purpose of repair, maintenance or improvement of any
of the IMPAC Servers. However, IMPAC shall provide notice where it is reasonably
practical under the circumstances, and IMPAC shall restore service as soon as it
is reasonably practicable. Customer shall not be entitled to any setoff,
discount, refund or other credit.
     2.3.6. Security IMPAC will provide secure and private access to
Customer's database. Customer is responsible for protecting its private
passwords, files and controlling its staff access in accordance with current
documentation. Customer is solely responsible for any damage caused by
unauthorized access of the IMPAC Servers through Customer's account. Any attempt
to undermine or cause harm to a server, or customer, of IMPAC is strictly
prohibited.

3.   Activation and Acceptance
3.1. Activation The IMPAC Products shall be made available to Customer on the
scheduled network activation date specified on the cover page by giving Customer
access to the IMPAC Server through a secure account and making the ordered IMPAC
Product available for use. In the event the scheduled network activation date is
not specified on the cover page, IMPAC shall provide Customer with

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
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Exhibit D

notification of a mutually agreed upon scheduled network activation date. In the
event Customer desires to change the scheduled network activation date, Customer
shall so advise IMPAC in writing and shall pay any delay charges assessed by
IMPAC. Upon request, IMPAC shall advise Customer of the amount of such delay
charges.

3.2.   Delays IMPAC shall not be liable for any damages or penalty for delay in
delivery or for failure to give notice of delay including, but not limited to,
delays in transportation and delays in delivery by Third Party Suppliers or
IMPAC's other vendors.

3.3.   Acceptance Customer shall inspect the IMPAC Product and ASP Service
promptly upon notice of activation. Unless Customer objects in writing within
five (5) business days after the first of completion of training or first
clinical use whichever is applicable, Customer shall be deemed to have accepted
the IMPAC Product and ASP Service as of the actual network activation date
("Acceptance"). All claims for errors or shortages in the IMPAC Products shall
be made by Customer in writing within such five (5) business day period.

4.     Fees and Taxes
4.1.   Fees All first year license, setup and hosting fees for the IMPAC
Products shall be payable as set forth on the cover page. In the event the
Products are installed in installments, Customer shall be invoiced separately
for each installment. All Product purchase prices or license fees are F.O.B.
destination (or if Customer is located outside of the United States, EXW IMPAC's
facility per Incoterms 2000). All payments shall be due and payable on
Customer's receipt of an invoice from IMPAC. Unless otherwise expressly set
forth herein, all prices stated in this Agreement are in U.S. dollars and all
payments shall be made in U.S. dollars. In the event that payment is not
received within fifteen (15) days after the renewal date, access to the IMPAC
Servers will be restricted. Customer's obligation to pay all accrued charges
shall survive the expiration or termination of this Agreement.

4.2.   Taxes and Other Charges The amounts payable to IMPAC hereunder
are exclusive of any sales, use, or other taxes or governmental charges.
Customer shall be responsible for payment of all such taxes or charges except
for any taxes based solely on IMPAC's net income. If Customer is required to pay
any taxes based on this Section 4, Customer shall pay such taxes with no
reduction or offset in the amounts payable to IMPAC hereunder. At IMPAC's
option, Customer shall make best efforts in assisting IMPAC to obtain any
ruling, withholding-exemption certificate, or similar certificate or document
related to any potential tax liability arising from this Agreement that IMPAC,
in its opinion, believes is appropriate. Customer shall comply with any ruling,
certificate, or similar government document. Customer agrees to provide IMPAC
any and all available evidence of any tax payments that is required or useful
under United States tax laws and that IMPAC periodically requests.
Notwithstanding the above, the amounts payable to IMPAC hereunder, shall be
exclusive of value added tax ("VAT") liability, if any, together with
VAT-related charges or penalties. Customer shall self-assess VAT, under the
reverse charge mechanism, for payments to IMPAC. In the event that IMPAC is
required to charge VAT or incurs VAT-related charges or penalties, Customer
shall pay to IMPAC the amount thereof in addition to fees and other amounts
hereunder. In the event any tangible product is shipped to Customer hereunder,
Customer shall be the importer of record for any such tangible product and shall
pay any import VAT. Customer shall also pay or reimburse IMPAC for all delivery,
transportation, insurance, and similar out-of-pocket charges incurred by IMPAC
which shall be separately set forth on IMPAC's invoice to Customer.

5.     Maintenance and Support
5.1.   Maintenance and Support by IMPAC
       5.1.1. Maintenance and Support Services for IMPAC Products Subject to the
terms, conditions and fees set forth in this Section 5, IMPAC will provide
Customer with the maintenance and support services specified in this Section for
the IMPAC Products. IMPAC will; (i) install IMPAC

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
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<PAGE>

Exhibit D

Products on IMPAC Servers and provide initial training for IMPAC Products at the
Customer site(s) as applicable and specified on the cover page; (ii) provide
such assistance as is necessary to cause the IMPAC Product to perform
substantially in accordance with its Documentation by providing a suitable
"fix," "patch," or "work around" for the problem or a statement that an
appropriate "fix" will be included in a future release of the IMPAC Product, the
time period within which the release is expected to be issued and a commitment
to provide the release at no cost to Customer; (iii) maintain a support desk for
receipt of Customer telephone calls for first level diagnosis of IMPAC Product
problems during the hours of 5:00 a.m. to 5:00 p.m. Pacific time, Monday through
Friday, IMPAC holidays excepted; (iv) provide emergency beeper service during
the hours of 5:00 a.m. to 5:00 p.m. Pacific time during IMPAC holidays; and (v)
provide upgrades of new releases for licensed IMPAC Products by means of
installing them on the IMPAC Server. Current IMPAC holidays are the following in
the United States: New Year's Day, Presidents Day, Memorial Day, Independence
Day, Labor Day, Thanksgiving Day, day after Thanksgiving, Christmas Eve Day, and
Christmas Day. IMPAC will inform Customer of any changes to IMPAC holidays. If
IMPAC is unable, after reasonable effort, to cause the IMPAC Product to perform
substantially in accordance with its Documentation, then this Agreement may be
terminated with respect to the IMPAC Product at the option of either party
hereto without further obligation or liability except as provided in Section
10.3 below, and such termination shall be Customer's exclusive remedy and
IMPAC's sole liability in connection with the failure of any IMPAC Product to
perform substantially in accordance with its Documentation. In the event this
Agreement is terminated during the initial ninety (90) day limited warranty
period for an IMPAC Product or ASP Service, IMPAC shall refund to Customer all
fees paid by Customer for such Product and/or ASP Service. Setup and
Installation fees are non-refundable. IMPAC shall have no liability for misuse
or modification of the IMPAC Product by Customer. New IMPAC Products are not
included in IMPAC's standard maintenance and support services and will be
offered by IMPAC to Customer at IMPAC's then current published prices and on
such other terms and conditions as are acceptable to IMPAC.

       5.1.2. Maintenance and Support IMPAC will provide customer with extended
maintenance and support as described in Section 5.1.1 above, provided Customer
pays IMPAC in advance the monthly ASP fee then in effect. The current monthly
ASP fee is specified on the cover page.
       5.1.3. Limitations on IMPAC's Obligations Customer understands and agrees
that IMPAC may develop and market new or different computer programs which use
part or all of the IMPAC Product and which perform all or part of the functions
performed by the IMPAC Product. Nothing contained in this Agreement gives
Customer any rights with respect to such new or different computer programs.
       5.1.4. Customer's Duties Customer will; (i) maintain proper local work
stations, local area networking, and wide area networking at the site in
accordance with the Documentation to provide sufficient local connectivity and
bandwidth to provide adequate system performance; (ii) maintain only IMPAC
approved software on local workstations and over the local area network; (iii)
perform routine maintenance as required by the Documentation for the IMPAC
Products and Other Products; (iv) schedule adequate time during normal business
hours for required on-site installation and training; and (v) perform such other
routine maintenance procedures as IMPAC may reasonably request from time to
time.

5.2.   Maintenance and Support by Third Party Suppliers Maintenance and support
of the Other Products by Third Party Suppliers shall not be provided by IMPAC,
unless otherwise agreed to between the parties, and shall only be provided in
accordance with the terms and conditions of such Third Party Suppliers' standard
agreements assigned to Customer pursuant to Section 2.2 above. IMPAC shall use
its reasonable efforts to assist Customer in obtaining maintenance and support
from such Third Party Suppliers, provided, however, that in the event such Third
Party Suppliers fail to maintain or support such Other Products, IMPAC shall
have no responsibility or liability by reason of such failure.

6.     LIMITATIONS ON LIABILITY
IN NO EVENT WILL IMPAC BE LIABLE FOR (1) INDIRECT, INCIDENTAL, COST OF

        IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View,
                   CA 94041 T/800.623.8800 F/650.6238911                    5/10

<PAGE>

Exhibit D

SUBSTITUTE PROCUREMENT, EXEMPLARY OR CONSEQUENTIAL DAMAGES OR (2) ANY DAMAGES
RESULTING FROM LOSS OF USE, DATA, OR PROFITS ARISING OUT OF, OR IN CONNECTION
WITH, THIS AGREEMENT RESULTING FROM ANY DEFECT IN THE PRODUCTS OR ANY FAILURE IN
THE ASP SERVICES EVEN IF IMPAC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
DAMAGES, AND REGARDLESS OF THE THEORY OF LIABILITY GIVING RISE TO SUCH DAMAGES.
CUSTOMER AGREES THAT IMPAC'S TOTAL MAXIMUM LIABILITY FOR DAMAGES, IF ANY, SHALL
NOT EXCEED THE SUMS PAID TO IMPAC BY CUSTOMER FOR THE IMPAC PRODUCTS AND ASP
SERVICES UNDER THIS AGREEMENT.

7.  Trade Secret, Patent, and Copyright Indemnification
IMPAC agrees to indemnify Customer and to hold it harmless from all damages
awarded against Customer and all reasonable expenses incurred by Customer as the
result of any third party claim of trade secret, patent, or copyright
infringement asserted against Customer by virtue of Customer's use of the IMPAC
Products as delivered by IMPAC, provided that IMPAC is given prompt notice of
any such claims and the right to control and direct the investigation,
preparation, defense, and settlement of each such claim, and further provided
that Customer shall fully cooperate with IMPAC in connection with the foregoing.
Should the IMPAC Product as delivered by IMPAC become or, in IMPAC's opinion, be
likely to become, the subject of a claim of infringement of a trade secret,
patent, or copyright, IMPAC may at its option and expense either (a) procure for
Customer the right to continue to use the IMPAC Product as contemplated
hereunder, or (b) replace or modify the IMPAC Product or modify its use to make
its use hereunder noninfringing. If neither option is reasonably available to
IMPAC, then this Agreement may be terminated with respect to the IMPAC Product
at the option of either party hereto without further obligation or liability
except as provided in Sections 10.3 hereof and IMPAC shall grant Customer a
refund for such IMPAC Product as depreciated on a five-year, straight-line
basis. IMPAC shall have no liability for any claim of trade secret, patent, or
copyright infringement under this Section based on; (i) Customer's use or
combination of the IMPAC Product with products or data not supplied by IMPAC as
part of the IMPAC Products; (ii) any modification of any IMPAC Product by a
party other than IMPAC; or (iii) Customer's failure to install changes or
updates as instructed by IMPAC.

8.  Modification of Product by Customer
Except as provided for in Section 2.1.5.(iii), any modification of the Product
by Customer or any failure by Customer to implement any improvements or updates
to the Product as supplied by IMPAC or Third Party Supplier shall void any and
all of IMPAC's obligations under this Agreement, whether expressed in this
Agreement or implied by law.

9.  Non-Disclosure and Confidentiality
9.1 Confidential Information The term "Confidential Information" means any
nonpublic information of a party, in oral, written, graphic or machine-readable
form, including without limitation that which relates to medical information
concerning patients and patient records, trade secrets, research, product plans,
products, inventions, processes, designs, algorithms, source code, programs,
business plans, agreements with third parties, services, customers, marketing or
finances, which is designated as confidential or proprietary by the disclosing
party at the time of disclosure, or which considering all the circumstances
surrounding the disclosure, ought reasonably to be understood by the receiving
party to be confidential.

9.2 Requirements and Restrictions on Confidential Information Each party will
not use any Confidential Information disclosed to it by the other for any
purpose other than to further potential business transactions and related
discussions between the parties. Neither party will disclose or permit
disclosure of any Confidential Information of the other party to third parties
or to employees, other than (a) directors, officers, employees, consultants,
attorneys, accountants, and agents of the receiving party

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
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<PAGE>

Exhibit D

who require that information in order to further potential business transactions
between the parties and who are bound by nondisclosure obligations sufficient to
enable the receiving party to comply with its obligations under this Agreement
or (b) to comply with applicable law. Each party will be liable for misuse
and/or improper disclosure of the other's Confidential Information by its
directors, officers, employees, consultants, attorneys, accountants, and agents.
Each party will maintain all Confidential Information of the other with the
strictest care and in trust for the sole and exclusive benefit of the disclosing
party. Each party agrees to notify the other in writing of any actual or
suspected misuse, misappropriation or unauthorized disclosure of Confidential
Information of the disclosing party which may come to the receiving party's
attention.

9.3     Exceptions Neither party will have any obligation under this Agreement
with respect to Confidential Information, other than patient identifiable data,
that: (a) is or subsequently becomes publicly available without breach of any
obligation under this Agreement; (b) was in the possession of the other party
prior to the time of first disclosure hereunder; (c) is developed by the other
party without any use of or reference to any Confidential Information received
from the first party; (d) is obtained without restriction from a third party
reasonably believed by the other party to be free to provide such information
without breach of any obligation owed to the first party; (e) is publicly
disclosed with the prior written approval of the other party; or (f) is
disclosed pursuant to the order or requirement of a court, administrative
agency, or other government body; provided, however, that the other party will
take all reasonable steps to provide first party with sufficient prior notice to
contest the order or requirement. If the receiving party claims that
Confidential Information received by it is subject to any of the exclusions
contained in clauses (a) through (f) above, it shall have the burden of
establishing the applicability of such exclusion by clear and convincing
documentary evidence.

9.4     Equitable Relief Customer agrees that its obligations under Sections 2
and 9 and IMPAC agrees that its obligations under Section 9 of this Agreement
are necessary and reasonable in order to protect the other party and its
business. Each party expressly agrees that due to the unique nature of the
other's Confidential Information, monetary damages would be inadequate to
compensate the other party for any breach by the receiving party of such
sections of this Agreement. Accordingly, each party agrees that any such breach
or threatened breach will cause irreparable injury to that party and that, in
addition to any other remedies that may be available, in law, equity or
otherwise, that party will be entitled to seek injunctive relief against the
threatened breach of this Agreement or the continuation of any such breach by
the other party, without the necessity of proving actual damages.

10.     Termination
10.1.   Basis for Terminationby IMPAC
        10.1.1. IMPAC shall have the right to terminate this Agreement
immediately upon written notice to Customer and without further obligation or
liability to Customer if Customer is delinquent in making payments of any sum
due under this Agreement and fails to remedy such breach within thirty (30) days
after written notice by IMPAC of such breach.
        10.1.2. IMPAC shall have the right to terminate this Agreement
immediately upon written notice to Customer and without further obligation or
liability to Customer if Customer commits any other breach of this Agreement.

10.2.   Basis for Termination by Customer Customer shall have the right to
terminate this Agreement upon written notice to IMPAC, without further
obligation or liability to IMPAC (except as specified in Sections 4, 9, 10.3 and
11.6 hereof) if any of the following events or conditions occur:
        10.2.1. IMPAC commits any breach of this Agreement and fails to remedy
such breach within thirty (30) days after written notice by Customer describing
such breach in reasonable detail; or
        10.2.2. Upon written notice of termination at least ninety (90) days
prior to the expiration of the initial term or the anniversary date of a renewal
term.

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
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Exhibit D

10.3. Disposition of Products on Termination
      10.3.1. IMPAC Product Upon the termination of this Agreement for any
reason, the license and all other rights granted to the Custo mer hereunder for
the IMPAC Product shall immediately cease, and IMPAC will terminate Customer's
remote access to the IMPAC Server. Customer shall immediately; (i) return all
copies of any documentation, notes, and other materials respecting the IMPAC
Product; (ii) purge all copies of the IMPAC Product or any portion thereof from
any computer storage device or medium on which Customer has placed or has
permitted others to place IMPAC Product; and (iii) give IMPAC a written
certification that Customer has complied with all of its obligations under
Section 10. Upon termination of this Agreement, IMPAC shall provide to Customer
a copy of Customer's database in its native format. Additional database reports
and services are available at the then current rates. IMPAC's termination of
this Agreement and termination of access to the IMPAC Product shall be without
prejudice to any other remedies IMPAC may lawfully have.
      10.3.2. Other Products Disposition of the Other Products shall be governed
by the terms and conditions of the Third Party Suppliers' standard agreements.
      10.3.3. Survival The terms and provisions of Sections 1, 2.1.8, 2.2
(Customer's obligations only), 4, 6, 7, 9, 10 and 11 of this Agreement shall
survive any termination or expiration of this Agreement.

11.   General
11.1. Relationship Between Parties The relationship established by this
Agreement between IMPAC and Customer shall be that of licensor and licensee.
Nothing contained in this Agreement shall constitute Customer as a partner,
joint venture, broker, employee, servant, or agent of or for IMPAC. Customer and
its employees, agents, or representatives will not make any representations that
IMPAC is in any way responsible for the acts or omissions of Customer or its
employees, agents, or representatives. Customer or Customer's employees, agents,
or representatives will not make any written or oral agreements or commitments
on behalf of IMPAC other than in accordance with this Agreement.

11.2. Attorneys' Fees In the event of any dispute arising hereunder, the
prevailing party shall be entitled to reasonable attorneys' fees in addition to
such other relief as the court may order.

11.3. Assignment This Agreement is not assignable without the prior written
consent of IMPAC. Any attempt to assign any of the rights, duties, or
obligations of this Agreement without such consent is void. Subject to the
foregoing, this Agreement shall be binding upon and inure to the benefit of the
parties and their respective successors and assigns.

11.4. Amendment This Agreement can only be modified by a written agreement duly
signed by persons authorized to sign agreements on behalf of IMPAC and of
Customer, and variance from, deletions of or additions to the terms and
conditions of this Agreement in any Customer Purchase Order or other written
notification from the Customer will be of no effect.

11.5. Waiver No waiver of any term or condition of this Agreement shall be
deemed to be a subsequent waiver of any other term or condition. No delay or
failure of a party to the Agreement to exercise a right under the Agreement
shall constitute a waiver or abandonment of that right.

11.6. Force Majeure Neither IMPAC nor Customer shall be deemed in default or be
liable for any delay, failure in performance, or interruption in service
resulting from circumstances beyond its reasonable control, including, without
limitation, riot, war, terrorism, fire, acts of God, or compliance with any
governmental law, regulation, or order. Provided any such delay is neither
material nor indefinite, performance shall be deemed suspended during and
extended for such time as it is so delayed, and thereafter the other party shall
accept performance hereunder.

    IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View, CA 94041
                          T/800.623.8800 F/650.6238911                      8/10

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Exhibit D

11.7.  Severability If any provision or provisions of this Agreement shall be
held to be invalid, illegal, or unenforceable, the validity, legality, and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby. The parties agree to replace such invalid, illegal or
unenforceable provision with a valid and enforceable provision which will
achieve, to the extent possible, the economic, business, and other purposes of
the invalid, illegal, or unenforceable provision.

11.8.  Limitation of Actions No action, regardless of form, arising out of any
of the transactions under this Agreement may be brought by Customer more than
one (1) year after such action has accrued. The parties hereby agree that any
suit to enforce provision of this Agreement arising out of or based upon this
Agreement or the business relationship between IMPAC and Customer shall be
brought in the United States District Court for the Northern District of
California or in the Superior Courts in and for Santa Clara County, California.
Each party irrevocably consents to the exclusive jurisdiction and venue of such
courts and irrevocably waives any right that such party may have to assert that
any such court lacks jurisdiction or is a forum non conveniens. Notwithstanding
the foregoing, either party may seek equitable relief in any court of competent
jurisdiction in order to protect its Confidential Information or intellectual
property rights. All communications and proceedings in connection herewith shall
be conducted in English.

11.9.  California Law This Agreement shall be governed by and constructed in
accordance with applicable United States federal law and the laws of the State
of California, without regard to conflicts of laws principles. The United
Nations Convention on Contracts for the International Sale of Goods shall not
apply to this Agreement.

11.10. Compliance with the Law Customer agrees that it will comply with all
applicable foreign, U.S. federal, state and local laws and regulations governing
the IMPAC Products and Customer's performance under this Agreement. THIS
AGREEMENT IS EXPRESSLY MADE SUBJECT TO ANY LAWS, REGULATIONS, ORDERS, OR OTHER
SUCH RESTRICTIONS ON THE EXPORT FROM THE UNITED STATES OF AMERICA OF PRODUCTS,
OR OF INFORMATION ABOUT SUCH PRODUCTS WHICH MAY BE IMPOSED FROM TIME TO TIME BY
THE GOVERNMENT OF THE UNITED STATES OF AMERICA. NOTWITHSTANDING ANYTHING
CONTAINED IN THIS AGREEMENT TO THE CONTRARY, CUSTOMER SHALL NOT EXPORT OR
REEXPORT, DIRECTLY OR INDIRECTLY, ANY PRODUCTS, OR INFORMATION PERTAINING
THERETO TO ANY COUNTRY OR DESTINATION OR PERMIT ITS TRANSSHIPMENT TO ANY COUNTRY
OR DESTINATION FOR WHICH SUCH GOVERNMENTAL APPROVAL IS REQUIRED AT THE TIME OF
EXPORT WITHOUT FIRST OBTAINING SUCH LICENSES OR APPROVAL. Customer shall be
responsible for obtaining all necessary import and export permits with respect
to the IMPAC Products. Neither Customer nor its directors, employees, agents or
anyone acting on Customer's behalf shall make any payment or give anything of
value, directly or indirectly, to any government official (including any
director, employee or agent of any government department, agency or
instrumentality) to influence his, her or its decision, or to gain any other
advantage for Customer in connection with this Agreement or the IMPAC Products.

11.11. Notice Any notice required or permitted under this Agreement will be in
writing and will be delivered in person or by means evidenced by a written
confirmation to the applicable party at the address set forth on the cover page
or to such other address as such party provides by giving notice in accordance
with this section. Notices will be effective only upon receipt.

11.12. Entire Agreement Customer acknowledges that it has read this Agreement,
understands it, and agrees to be bound by its terms and conditions. This
Agreement, any attachments, the cover page hereto and other documents referenced
herein are the complete and exclusive statement of the agreement

        IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View,
                   CA 94041 T/800.623.8800 F/650.6238911                    9/10

<PAGE>

Exhibit D                                                           USO/ASP 5/02

between the parties, which supersedes all proposals, marketing literature, any
Customer Purchase Orders or other written notification from the Customer, or
prior agreements, oral or written, and all other communications between the
parties relating to the subject matter of this Agreement.

11.13. English Language The parties declare that it is their express intention
that this Agreement be in English. Les parties aux presentes declarent que c'est
leur intention expresse que le present contract soit redige en anglais. Any
translation hereof into any language other than English shall be for convenience
only and shall be of no force or effect. The parties irrevocably waive any
rights they may have to have this Agreement drafted in or translated into any
other language.

        IMPAC Medical Systems, Inc. 100 West Evelyn Ave. Mountain View,
                   CA 94041 T/800.623.8800 F/650.6238911                   10/10

<PAGE>

Exhibit E

                             SERVICE LEVEL AGREEMENT
                                     BETWEEN
                           IMPAC MEDICAL SYSTEMS, INC.
                                       AND
                                US ONCOLOGY, INC.

Service Level - IMPAC ASP Model
IMPAC shall use its commercially reasonable efforts to provide *** uptime during
the hours of *** for IMPAC Software Products (see Exhibit B) and associated
hardware components (see Exhibit C) operating on the dedicated IMPAC network.
Downtime incurred because of hardware failure is not included in the downtime
calculation, except in the case of the verify and record system attached to the
Linacs at each site. In the event that IMPAC discovers or is notified by US
Oncology of the existence of non-scheduled downtime, IMPAC will take all actions
reasonably necessary to determine the source of the problem and to resolve such
problem as soon as possible.

If during the course of a *** downtime exceeds the *** threshold then IMPAC will
reduce the following *** fee by an amount to be determined by using the
calculation below. Downtime will be considered that duration of time in excess
of thirty minutes during the hours specified above that the IMPAC Software
Product and ASP Service is not available US Oncology and will commence from the
time that a US Oncology ASP Site notifies IMPAC Client Services of a disruption
in service. Downtime shall not include those instances that are not reasonably
foreseeable by or within the reasonable control of IMPAC, including Force
Majeure events and loss of power at the US Oncology ASP Site location level.
Additional exclusions from downtime include without limitation the negligence of
US Oncology or delays in resolving the problem due to the actions or inactions
of US Oncology (such as US Oncology not providing access to its site, delayed
maintenance due to rescheduling or the unavailability to accept repairs by
IMPAC).

Service Level - Calculation
The following calculation will be used to calculate downtime on a per site basis
in excess of the *** threshold. This percentage will be deducted on a
corresponding percentage basis from the amount due for the following *** fees or
if the agreement is in the ***, the dollar amount that will be refunded to US
Oncology.

Single Site Downtime Credit = ***

Cluster Downtime Credit# = *** x # of sites in cluster

#Calculation to be used when downtime affects the entire cluster.

*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.