S-1/A

As filed with the Securities and Exchange Commission on June 20, 2002

Registration No. 333-89724

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 1

TO

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

IMPAC MEDICAL SYSTEMS, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware (State or other jurisdiction of incorporation or organization) 7372 (Primary Standard Industrial Classification Code Number) 94-3109238 (I.R.S. Employer Identification Number)

100 West Evelyn Avenue, Mountain View, California 94041

(650) 623-8800

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Joseph K. Jachinowski

President and Chief Executive Officer

IMPAC Medical Systems, Inc.

100 West Evelyn Avenue

Mountain View, California 94041

(650) 623-8800

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Alan Talkington Brett E. Cooper John M. Beer Orrick, Herrington & Sutcliffe LLP 400 Sansome Street San Francisco, California 94111-3143 (415) 392-1122 Jeffrey D. Saper Jack Helfand Craig N. Lang Wilson Sonsini Goodrich & Rosati Professional Corporation 650 Page Mill Road Palo Alto, California 94304 (650) 493-9300

Approximate date of commencement of proposed sale to the public:

As soon as practicable after this Registration Statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, check the following box.  ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box.  ¨

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price(1)		Amount of Registration Fee(2)
Common Stock, $0.001 par value per share	$	50,600,000	$	4,656

(1) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

(2) Estimated pursuant to Rule 457(a) under the Securities Act of 1933, as amended, based on an estimate of the proposed maximum aggregate offering price.

The registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until this Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 13.    OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.

The following table sets forth the costs and expenses, other than underwriting discounts and commissions, payable by us in connection with the sale of common stock being registered. All amounts are estimates except the SEC registration fee; the NASD filing fee and the Nasdaq National Market listing fee.

	Amount to be Paid
SEC registration fee	$	4,656
NASD filing fee		5,560
Nasdaq National Market listing fee		*
Printing and engraving expenses		*
Legal fees and expenses		*
Accounting fees and expenses		500,000
Blue sky qualification fees and expenses		*
Transfer agent and registrar fees		*
Miscellaneous fees and expenses		*
Total	$

* to be filed by amendment

ITEM 14.    INDEMNIFICATION OF DIRECTORS AND OFFICERS.

Article XIV of our restated certificate of incorporation provides that our directors shall not be personally liable to us or our stockholders for monetary damages for breach of fiduciary duty as a director, to the fullest extent permitted by the General Corporation Law of the State of Delaware. Article VI of our bylaws provides for indemnification of officers and directors to the full extent and in the manner permitted by Delaware law. Section 145 of the Delaware General Corporation Law makes provision for such indemnification in terms sufficiently broad to cover officers and directors under certain circumstances for liabilities arising under the Securities Act of 1933, as amended (the “Securities Act”).

We have entered into indemnification agreements with each director which provide indemnification under certain circumstances for acts and omissions which may not be covered by any directors’ and officers’ liability insurance. The indemnification agreements may require us, among other things, to indemnify our officers and directors against certain liabilities that may arise by reason of their status or service as officers and directors (other than liabilities arising from willful misconduct of a culpable nature), to advance their expenses incurred as a result of any proceeding against them as to which they could be indemnified, and to obtain officers’ and directors’ insurance if available on reasonable terms.

The form of underwriting agreement, filed as Exhibit 1.1 to the Registration Statement, provides for indemnification of us and our controlling persons against certain liabilities under the Securities Act.

ITEM 15.    RECENT SALES OF UNREGISTERED SECURITIES.

Since May 1, 1999, we have sold and issued the following unregistered securities:

1. Since May 1, 1999, we have issued options to purchase an aggregate of 657,500 shares of our common stock under our 1993 stock option plan and 1998 stock plan to a number of our employees and directors, 207,359 shares of which have been exercised at purchase prices ranging from $0.32 per share to $7.00 per share.

II-1

The issuances of the above securities were deemed to be exempt from registration under the Securities Act in reliance on:

• Rule 701 promulgated under the Securities Act; or

• Section 4(2) of such Securities Act as transactions by an issuer not involving any public offering.

The recipients of securities in each such transaction represented their intentions to acquire the securities for investment only and not with a view to or for sale in connection with any distribution thereof and appropriate legends were affixed to the share certificates issued in such transactions. All recipients had adequate access, through their relationships with us, to information about us.

ITEM 16.    EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

(a)  Exhibits

Number	Description
1.1	Form of Underwriting Agreement.
3.1	Certificate of Incorporation.*
3.2	Form of Amended and Restated Certificate of Incorporation to be effective upon closing of the offering.*
3.3	Bylaws.*
3.4	Form of Amended and Restated Bylaws to be effective upon closing.*
4.1	Specimen Stock Certificate.**
5.1	Opinion of Orrick, Herrington & Sutcliffe LLP regarding the legality of the common stock being registered.**
10.1	Software Distribution Agreement dated April 25, 2001 between IMPAC and Siemens Medical Systems, Inc.†
10.2	Application Service Provider (ASP) Agreement dated May 31, 2002 between IMPAC and US Oncology, Inc.†
10.3	Lease Agreement dated September 1, 1999 between the Revocable Living Trust dated March 23, 1987, Hillview Management, Inc. and IMPAC, as amended, for the premises in Mountain View, California.*
10.3.1	Second Addendum dated March 23, 2000 to Lease Agreement dated September 1, 1999 between the Revocable Living Trust dated March 23, 1987, Hillview Management, Inc. and IMPAC for the premises in Mountain View, California.
10.4	Form of Indemnification Agreement between IMPAC and each of its officers and directors.*
10.5	1993 Stock Option Plan.*
10.6	1998 Stock Plan.*
10.7	2002 Stock Plan.*
10.8	2002 Employee Stock Purchase Plan.*
10.9	Form of Incentive Stock Option Agreement for 2002 Stock Plan.*
10.10	Form of Nonqualified Stock Option Agreement for 2002 Stock Plan.*
10.11	Investor Rights Agreement dated October 9, 1996 between IMPAC and the investors therein.*
21.1	List of Subsidiaries of IMPAC.*
23.1	Consent of Independent Accountants.*
23.2	Consent of Orrick, Herrington & Sutcliffe LLP (included in Exhibit 5.1).**
24.1	Power of Attorney (included on page II-4).*

II-2

* Previously Filed.

** To be supplied by amendment.

† Confidential treatment requested as to certain portions of this Exhibit.

(b)  Financial Statement Schedules

The following schedule is filed herewith:

Schedule II—Valuation and Qualifying Accounts

Schedules not listed above have been omitted because the information required to be set forth therein is not applicable or is shown in the financial statements or notes thereto.

Item 17.    UNDERTAKINGS.

We hereby undertake to provide to the underwriters at the closing specified in the underwriting agreement certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to our directors, officers and controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act, and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by us of expenses incurred or paid by a director, officer, or controlling person of ours in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, we will, unless in the opinion of our counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by us is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

We hereby undertake that:

(1)  For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by us pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

(2)  For the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

II-3

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, we have duly caused this Registration Statement to be signed on our behalf by the undersigned, thereunto duly authorized, in the city of Mountain View, State of California on June 18, 2002.

IMPAC MEDICAL SYSTEMS, INC.
By:	/s/    JOSEPH K. JACHINOWSKI
	Joseph K. Jachinowski President and Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated:

Signature	Title	Date
/s/    JOSEPH K. JACHINOWSKI         Joseph K. Jachinowski	Chairman of the Board of Directors, President and Chief Executive Officer (Principal Executive Officer)	June 18, 2002
/s/    KENDRA A. BORREGO        Kendra A. Borrego	Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)	June 18, 2002
* James P. Hoey	Director, Executive Vice President Chief Operations Officer	June 18, 2002
* David A. Auerbach	Director, Executive Vice President and Treasurer	June 18, 2002
* Gregory M. Avis	Director	June 18, 2002
* Robert J. Becker, M.D.	Director	June 18, 2002
* Christopher M. Rose, M.D.	Director	June 18, 2002

*By:	/s/    JOSEPH K. JACHINOWSKI
	Joseph K. Jachinowski Attorney-in-Fact

II-4

EXHIBIT INDEX

The following exhibits are filed as part of this Form S-1 Registration Statement.

Number	Description
1.1	Form of Underwriting Agreement.
3.1	Certificate of Incorporation.*
3.2	Form of Amended and Restated Certificate of Incorporation to be effective upon closing of the offering.*
3.3	Bylaws.*
3.4	Form of Amended and Restated Bylaws to be effective upon closing.*
4.1	Specimen Stock Certificate.**
5.1	Opinion of Orrick, Herrington & Sutcliffe LLP regarding the legality of the common stock being registered.**
10.1	Software Distribution Agreement dated April 25, 2001 between IMPAC and Siemens Medical Systems, Inc.†
10.2	Application Service Provider (ASP) Agreement dated May 31, 2002 between IMPAC and US Oncology, Inc.†
10.3	Lease Agreement dated September 1, 1999 between the Revocable Living Trust dated March 23, 1987, Hillview Management, Inc. and IMPAC, as amended, for the premises in Mountain View, California.*
10.3.1	Second Addendum dated March 23, 2000 to lease Agreement dated September 1, 1999 between the Revocable Living Trust dated March 23, 1987, Hillview Management, Inc. and IMPAC for the premises in Mountain View, California.
10.4	Form of Indemnification Agreement between IMPAC and each of its officers and directors.*
10.5	1993 Stock Option Plan.*
10.6	1998 Stock Plan.*
10.7	2002 Stock Plan.*
10.8	2002 Employee Stock Purchase Plan.*
10.9	Form of Incentive Stock Option Agreement for 2002 Stock Plan.*
10.10	Form of Nonstatutory Stock Option Agreement for 2002 Stock Plan.*
10.11	Investor Rights Agreement dated October 9, 1996 between IMPAC and the investors therein.*
21.1	List of Subsidiaries of IMPAC.*
23.1	Consent of Independent Accountants.*
23.2	Consent of Orrick, Herrington & Sutcliffe LLP (included in Exhibit 5.1).**
24.1	Power of Attorney (included on page II-4).*

* Previously filed.

** To be supplied by amendment.

† Confidential treatment requested as to certain portions of this Exhibit.

EX-1.1

                                                                     EXHIBIT 1.1

                             ________________ Shares





                           IMPAC MEDICAL SYSTEMS, INC.


                    COMMON STOCK (Par value $0.001 per share)




                             UNDERWRITING AGREEMENT


                           Dated ______________, 2002



                               _____________, 2002

Thomas Weisel Partners LLC
U.S. Bancorp Piper Jaffray
SG Cowen Securities Corporation
c/o Thomas Weisel Partners LLC
One Montgomery Street, Suite 3700
San Francisco, California 94104

Ladies and Gentlemen:

     Introduction. IMPAC Medical Systems, Inc., a Delaware corporation (the
"Company"), proposes to issue and sell to the several underwriters named in
Schedule A hereto (the "Underwriters") an aggregate of ____________ shares of
the Common Stock, par value $0.001 per share, of the Company (the "Firm
Shares").

     Certain stockholders of the Company (the "Selling Stockholders") named in
Schedule B hereto severally propose to sell to the several Underwriters an
aggregate of ____________ shares of the Company's Common Stock, par value $0.001
per share (the "Additional Shares"), with each Selling Stockholder selling the
number of shares set forth opposite such Selling Stockholder's name in Schedule
B hereto, if and to the extent that you shall have determined to exercise, on
behalf of the Underwriters, the right to purchase such shares of common stock
granted to the Underwriters in Section 3 hereof. The Firm Shares and the
Additional Shares are hereinafter collectively referred to as the "Shares." The
shares of Common Stock, par value $0.001 per share, of the Company to be
outstanding after giving effect to the sales contemplated hereby are hereinafter
referred to as the "Common Stock." The Company and the Selling Stockholders are
hereinafter collectively referred to as the "Sellers." Thomas Weisel Partners
LLC ("Thomas Weisel Partners"), U.S. Bancorp Piper Jaffray and SG Cowen
Securities Corporation have agreed to act as representatives of the several
Underwriters (in such capacity, the "Representatives") in connection with the
offering and sale of the Shares.

     The Company has filed with the Securities and Exchange Commission (the
"Commission") a registration statement on Form S-1 (file no. 333-_____),
including a prospectus, relating to the Shares. The registration statement as
amended at the time it becomes effective, including the information (if any)
deemed to be part of the registration statement at the time of effectiveness
pursuant to Rule 430A under the Securities Act of 1933, as amended (the
"Securities Act"), is hereinafter referred to as the "Registration Statement";
the prospectus in the form first used to confirm sales of Shares is hereinafter
referred to as the "Prospectus." If the Company has filed a registration
statement to register additional shares of Common Stock pursuant to Rule 462(b)
under the Securities Act (the "Rule 462 Registration Statement"), then any
reference herein to the term "Registration Statement" shall be deemed to include
such Rule 462 Registration Statement. All references in this Agreement to the
Registration Statement, the Rule 462 Registration Statement, a preliminary
prospectus, the Prospectus, or any amendments or supplements to any of the
foregoing, shall include any copy thereof filed with the Commission pursuant to
its Electronic Data Gathering, Analysis and Retrieval System ("EDGAR").

     As part of the offering contemplated by this Agreement, Thomas Weisel
Partners has agreed to reserve out of the Shares set forth opposite its name on
Schedule A to this Agreement, up to ______________ shares, for sale to the
Company's employees, officers, and directors and other parties associated with
the



Company (collectively, "Participants"), as set forth in the Prospectus under the
heading "Underwriting" (the "Directed Share Program"). The Shares to be sold by
Thomas Weisel Partners pursuant to the Directed Share Program (the "Directed
Shares") will be sold by Thomas Weisel Partners pursuant to this Agreement at
the public offering price. Any Directed Shares not orally confirmed for purchase
by any Participants by the end of the first business day after the date on which
this Agreement is executed will be offered to the public by Thomas Weisel
Partners as set forth in the Prospectus.

     1.    Representations and Warranties of the Company. The Company represents
and warrants to and agrees with each of the Underwriters that:

           1.1   Effective Registration Statement. The Registration Statement
has become effective; no stop order suspending the effectiveness of the
Registration Statement is in effect, and no proceedings for such purpose are
pending before or, to the knowledge of the Company, threatened by the
Commission.

           1.2   Contents of Registration Statement. (i) The Registration
Statement, when it became effective, did not contain and, as amended or
supplemented, if applicable, will not contain any untrue statement of a material
fact or omit to state a material fact required to be stated therein or necessary
to make the statements therein not misleading, (ii) the Registration Statement
and the Prospectus comply and, as amended or supplemented, if applicable, will
comply in all material respects with the Securities Act and the applicable rules
and regulations of the Commission thereunder and (iii) the Prospectus does not
contain and, as amended or supplemented, if applicable, will not contain any
untrue statement of a material fact or omit to state a material fact necessary
to make the statements therein, in the light of the circumstances under which
they were made, not misleading, except that the representations and warranties
set forth in this paragraph do not apply to statements or omissions in the
Registration Statement or the Prospectus based upon information relating to any
Underwriter furnished to the Company in writing by such Underwriter through you
expressly for use therein.

           1.3   Due Incorporation. The Company has been duly incorporated, is
validly existing as a corporation in good standing under the laws of the
jurisdiction of its incorporation, has the corporate power and authority to own
its property and to conduct its business as described in the Prospectus and is
duly qualified to transact business and is in good standing in each jurisdiction
in which the conduct of its business or its ownership or leasing of property
requires such qualification, except to the extent that the failure to be so
qualified or be in good standing would not have a material adverse effect on the
Company and its subsidiaries, taken as a whole.

           1.4   Subsidiaries. Each subsidiary of the Company has been duly
incorporated, is validly existing as a corporation in good standing under the
laws of the jurisdiction of its incorporation, has the corporate power and
authority to own its property and to conduct its business as described in the
Prospectus and is duly qualified to transact business and is in good standing in
each jurisdiction in which the conduct of its business or its ownership or
leasing of property requires such qualification, except to the extent that the
failure to be so qualified or be in good standing would not have a material
adverse effect on the Company and its subsidiaries, taken as a whole. All of the
issued shares of capital stock of each subsidiary of the Company have been duly
and validly authorized and issued, are fully paid and non-assessable and are
owned directly or indirectly by the Company, free and clear of all liens,
encumbrances, equities or claims.

           1.5   Underwriting Agreement. This Agreement has been duly
authorized, executed and delivered by the Company, and is a valid and binding
agreement of the Company, enforceable in accordance with its terms, except as
rights to indemnification hereunder may be limited by applicable law and except
as the enforcement hereof may be limited by bankruptcy, insolvency,
reorganization, moratorium or other similar laws relating to or affecting the
rights and remedies of creditors or by general equitable principles.

                                                                             -2-



           1.6   Description of Capital Stock. The authorized capital stock of
the Company conforms as to legal matters to the description thereof contained in
the Prospectus.

           1.7   Authorized Stock. The shares of Common Stock outstanding prior
to the issuance of the Shares to be sold by the Company have been duly
authorized and are validly issued, fully paid and non-assessable.

           1.8   Validly Issued Shares. The Shares to be sold by the Company
have been duly authorized and, when issued and delivered in accordance with the
terms of this Agreement, will be validly issued, fully paid and non-assessable,
and the issuance of such Shares will not be subject to any preemptive or similar
rights.

           1.9   No Conflict. The execution and delivery by the Company of, and
the performance by the Company of its obligations under, this Agreement will not
contravene any provision of applicable law or the certificate of incorporation
or by-laws of the Company or any agreement or other instrument binding upon the
Company or any of its subsidiaries that is material to the Company and its
subsidiaries, taken as a whole, or any judgment, order or decree of any
governmental body, agency or court having jurisdiction over the Company or any
subsidiary, and no consent, approval, authorization or order of, or
qualification with, any governmental body or agency is required for the
performance by the Company of its obligations under this Agreement, except such
as may be required by the securities or Blue Sky laws of the various states in
connection with the offer and sale of the Shares.

           1.10  No Material Adverse Change. There has not occurred any material
adverse change or any development involving a prospective material adverse
change, in the condition, financial or otherwise, or in the earnings, business
or operations of the Company and its subsidiaries, taken as a whole, from that
set forth in the Prospectus (exclusive of any amendments or supplements thereto
subsequent to the date of this Agreement).

           1.11  Absence of Material Charges. Subsequent to the respective dates
as of which information is given in the Registration Statement and the
Prospectus, (1) the Company and its subsidiaries have not incurred any material
liability or obligation, direct or contingent, nor entered into any material
transaction not in the ordinary course of business; (2) the Company has not
purchased any of its outstanding capital stock, nor declared, paid or otherwise
made any dividend or distribution of any kind on its capital stock other than
ordinary and customary dividends; and (3) there has not been any material change
in the capital stock, short-term debt or long-term debt of the Company and its
subsidiaries, except in each case as described in the Prospectus.

           1.12  Compliance with Securities Act. Each preliminary prospectus
filed as part of the registration statement as originally filed or as part of
any amendment thereto, or filed pursuant to Rule 424 under the Securities Act,
complied when so filed in all material respects with the Securities Act and the
applicable rules and regulations of the Commission thereunder.

           1.13  Legal Proceedings; Exhibits. There are no legal or governmental
proceedings pending or, to the knowledge of the Company, threatened to which the
Company or any of its subsidiaries is a party or to which any of the properties
of the Company or any of its subsidiaries is subject that are required to be
described in the Registration Statement or the Prospectus and are not so
described or any statutes, regulations, contracts or other documents that are
required to be described in the Registration Statement or the Prospectus or to
be filed as exhibits to the Registration Statement that are not described or
filed as required.

                                                                             -3-



           1.14  Compliance with Environmental Laws. The Company and its
subsidiaries (i) are in compliance with any and all applicable foreign, federal,
state and local laws and regulations relating to the protection of human health
and safety, the environment or hazardous or toxic substances or wastes,
pollutants or contaminants ("Environmental Laws"), (ii) have received all
permits, licenses or other approvals required of them under applicable
Environmental Laws to conduct their respective businesses and (iii) are in
compliance with all terms and conditions of any such permit, license or
approval, except where such noncompliance with Environmental Laws, failure to
receive required permits, licenses or other approvals or failure to comply with
the terms and conditions of such permits, licenses or approvals would not,
individually or in the aggregate, have a material adverse effect on the Company
and its subsidiaries, taken as a whole.

           1.15  No Environmental Costs. There are no costs or liabilities
associated with Environmental Laws (including, without limitation, any capital
or operating expenditures required for clean-up, closure of properties or
compliance with Environmental Laws or any permit, license or approval, any
related constraints on operating activities and any potential liabilities to
third parties) which would, individually or in the aggregate, have a material
adverse effect on the Company and its subsidiaries, taken as a whole.

           1.16  No Registration Rights. There are no contracts, agreements or
understandings between the Company and any person granting such person the right
to require the Company to file a registration statement under the Securities Act
with respect to any securities of the Company or to require the Company to
include such securities with the Shares registered pursuant to the Registration
Statement other than as described in the Registration Statement and as have been
waived in writing in connection with the offering contemplated hereby.

           1.17  Not an Investment Company. The Company is not and, after giving
effect to the offering and sale of the Shares and the application of the
proceeds thereof as described in the Prospectus, will not be an "investment
company" as such term is defined in the Investment Company Act of 1940, as
amended.

           1.18  Good Title to Properties. The Company and its subsidiaries have
good and marketable title in fee simple to all real property and good and
marketable title to all personal property owned by them which is material to the
business of the Company and its subsidiaries, in each case free and clear of all
liens, encumbrances and defects except such as are described in the Prospectus
or such as do not materially affect the value of such property and do not
interfere with the use made and proposed to be made of such property by the
Company and its subsidiaries; and any real property and buildings held under
lease by the Company and its subsidiaries are held by them under valid,
subsisting and enforceable leases with such exceptions as are not material and
do not interfere with the use made and proposed to be made of such property and
buildings by the Company and its subsidiaries.

           1.19  Intellectual Property Rights. The Company and its subsidiaries
own or possess, or can acquire on reasonable terms, all material patents, patent
rights, licenses, inventions, copyrights, know-how (including trade secrets and
other unpatented and/or unpatentable proprietary or confidential information,
systems or procedures), trademarks, service marks and trade names currently
employed by them in connection with the business now operated by them, and
neither the Company nor any of its subsidiaries has received any notice of
infringement of or conflict with asserted rights of others with respect to any
of the foregoing which, individually or in the aggregate, if the subject of an
unfavorable decision, ruling or finding, would have a material adverse affect on
the Company and its subsidiaries, taken as a whole.

           1.20  No Labor Disputes. No material labor dispute with the employees
of the Company or any of its subsidiaries exists, or, to the knowledge of the
Company, is imminent; and the Company is not

                                                                             -4-



aware of any existing, threatened or imminent labor disturbance by the employees
of any of its principal suppliers, manufacturers or contractors that could have
a material adverse effect on the Company and its subsidiaries, taken as a whole.

           1.21  Insurance. The Company and its subsidiaries are insured by the
insurers of recognized financial responsibility against such losses and risks
and in such amounts as are prudent and customary in the businesses in which they
are engaged; and neither the Company nor any of its subsidiaries has any reason
to believe that it will not be able to renew its existing insurance coverage as
and when such coverage expires or to obtain similar coverage from similar
insurers as may be necessary to continue its business at a cost that would not
have a material adverse effect on the Company and its subsidiaries, taken as a
whole.

           1.22  Governmental Permits. The Company and its subsidiaries possess
all certificates, authorizations and permits issued by the appropriate federal,
state or foreign regulatory authorities necessary to conduct their respective
business, except where the failure to possess such certificate, authorization or
permit would not, individually or in the aggregate, have a material adverse
effect on the Company and its subsidiaries, taken as a whole. Neither the
Company nor any of its subsidiaries has received any notice of proceedings
relating to the revocation or modification of any such certificate,
authorization or permit which, individually or in the aggregate, if the subject
of an unfavorable decision, ruling or finding, would have a material adverse
effect on the Company and its subsidiaries, taken as a whole.

           1.23  Accounting Controls. The Company and each of its subsidiaries
maintain a system of internal accounting controls sufficient to provide
reasonable assurance that (1) transactions are executed in accordance with
management's general or specific authorizations; (2) transactions are recorded
as necessary to permit preparation of financial statements in conformity with
generally accepted accounting principles and to maintain asset accountability;
(3) access to assets is permitted only in accordance with management's general
or specific authorization; and (4) the recorded accountability for assets is
compared with the existing assets at reasonable intervals and appropriate action
is taken with respect to any differences.

           1.24  Directed Share Program. The Company represents and warrants to
Thomas Weisel Partners that (i) the Registration Statement, the Prospectus and
any preliminary prospectus comply, and any further amendments or supplements
thereto will comply, with any applicable laws or regulations of foreign
jurisdictions in which the Prospectus or any preliminary prospectus, as amended
or supplemented, if applicable, are distributed in connection with the Directed
Share Program, and that (ii) no authorization, approval, consent, license,
order, registration or qualification of or with any government, governmental
instrumentality or court, other than such as have been obtained, is necessary
under the securities laws and regulations of foreign jurisdictions in which the
Directed Shares are offered outside the United States.

           1.25  Compliance with Laws. To the Company's knowledge, the Company
and its subsidiaries are conducting their business in compliance with the Fair
Labor Standards Act, the rules and regulations of the federal Food and Drug
Administration, and all applicable federal, state and local laws, rules and
regulations of the jurisdictions in which it is conducting business, including,
without limitation, all applicable local, state and federal laws and regulations
governing health, sanitation, safety, environmental matters, zoning and land
use, except where the failure to be so in compliance would not have a material
adverse effect on the Company and its subsidiaries, taken as a whole.

     2.    Representations and Warranties of the Selling Stockholders.  Each of
the Selling Stockholders, severally and not jointly, represents and warrants to
and agrees with each of the Underwriters that:

                                                                             -5-



           2.1   Due Authorization. This Agreement has been duly authorized,
executed and delivered by or on behalf of such Selling Stockholder and is a
valid and binding agreement of such Selling Stockholder, enforceable in
accordance with its terms, except as rights to indemnification hereunder may be
limited by applicable law and except as the enforcement hereof may be limited by
bankruptcy, insolvency, reorganization, moratorium or other similar laws
relating to or affecting the rights and remedies of creditors or by general
equitable principles.

           2.2   Selling Stockholder Documents. The Custody Agreement and the
Power of Attorney have been duly authorized, executed and delivered by such
Selling Stockholder and are valid and binding agreements of such Selling
Stockholder enforceable in accordance with their respective terms, except as
rights to indemnification thereunder may be limited by applicable law and except
as the enforcement thereof may be limited by bankruptcy, insolvency,
reorganization, moratorium or other similar laws relating to or affecting the
rights and remedies of creditors or by general equitable principles.

           2.3   No Conflict. The execution and delivery by such Selling
Stockholder of, and the performance by such Selling Stockholder of its
obligations under, this Agreement, the Custody Agreement signed by such Selling
Stockholder and ____________, as Custodian, relating to the deposit of the
Shares to be sold by such Selling Stockholder (the "Custody Agreement") and the
Power of Attorney appointing certain individuals as such Selling Stockholder's
attorneys-in-fact to the extent set forth therein, relating to the transactions
contemplated hereby and by the Registration Statement (the "Power of Attorney")
will not contravene any provision of applicable law, or the certificate of
incorporation or by-laws of such Selling Stockholder (if such Selling
Stockholder is a corporation), or any agreement or other instrument binding upon
such Selling Stockholder or any judgment, order or decree of any governmental
body, agency or court having jurisdiction over such Selling Stockholder, and no
consent, approval, authorization or order of, or qualification with, any
governmental body or agency is required for the performance by such Selling
Stockholder of its obligations under this Agreement or the Custody Agreement or
Power of Attorney of such Selling Stockholder, except such as may be required by
the securities or Blue Sky laws of the various states in connection with the
offer and sale of the Shares.

           2.4   Good Title to Shares. Such Selling Stockholder has, and on each
Closing Date will have, valid title to the Shares to be sold by such Selling
Stockholder and the legal right and power, and all authorization and approval
required by law, to enter into this Agreement, the Custody Agreement and the
Power of Attorney and to sell, transfer and deliver the Shares to be sold by
such Selling Stockholder.

           2.5   Delivery of Common Shares. Delivery of the Shares to be sold by
such Selling Stockholder pursuant to this Agreement will pass title to such
Shares free and clear of any security interests, claims, liens, equities and
other encumbrances.

           2.6   No Registration Rights. Such Selling Stockholder does not have
any registration or other similar rights to have any equity or debt securities
registered for sale by the Company under the Registration Statement or included
in the offering contemplated by this Agreement, other than as described in the
Registration Statement and as have been waived in writing in connection with the
offering contemplated hereby.

           2.7   No Price Stabilization or Manipulation. Such Selling
Stockholder has not taken and will not take, directly or indirectly, any action
designed to or that might be reasonably expected to cause or result in
stabilization or manipulation of the price of the Common Stock to facilitate the
sale or resale of the Shares.

                                                                             -6-



           2.8   Disclosure by Selling Stockholder in Registration Statement.
Such portion of the Registration Statement comprised of the table and the notes
thereto under the caption "Principal and Selling Stockholders" in the form
supplied to such Selling Stockholders in so far as such portion specifically
related to such Selling Stockholder do not contain any untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading.

           2.9   Confirmation of Company Representations and Warranties. Each of
Joseph K. Jachinowski, James P. Hoey and David A. Auerbach (each a "Selling
Officer," and collectively the "Selling Officers") has no reason to believe that
the representations and warranties of the Company contained in Section 1 hereof
are not true and correct, is familiar with the Registration Statement and the
Prospectus and has no knowledge of any material fact, condition or information
not disclosed in the Registration Statement or the Prospectus which has had or
may have a material adverse effect on the Company and its subsidiaries, taken as
a whole, and is not prompted to sell any of the Shares by any information
concerning the Company which is not set forth in the Registration Statement and
the Prospectus.

     3.    Purchase and Sale Agreements.

           3.1   Firm Shares. The Company hereby agrees to sell to the several
Underwriters, and each Underwriter, upon the basis of the representations and
warranties herein contained, but subject to the conditions hereinafter stated,
agrees, severally and not jointly, to purchase from the Company at $______ a
share (the "Purchase Price") the number of Firm Shares set forth in Schedule A
hereto opposite the name of such Underwriter.

           3.2   Additional Shares. On the basis of the representations and
warranties contained in this Agreement, and subject to its terms and conditions,
each of the Selling Stockholders, severally and not jointly, agrees to sell to
the Underwriters the Additional Shares, and the Underwriters shall have a one
time right to purchase, severally and not jointly, up to _______________
Additional Shares at the Purchase Price. If you, on behalf of the Underwriters,
elect to exercise such option, you shall so notify the Company and the Selling
Stockholders in writing not later than thirty (30) days after the date of this
Agreement, which notice shall specify the number of Additional Shares to be
purchased by the Underwriters and the date on which such shares are to be
purchased. Such date may be the same as the Closing Date (as defined below) but
not earlier than the Closing Date nor later than ten (10) business days after
the date of such notice. Additional Shares may be purchased as provided in
Section 4 hereof solely for the purpose of covering over allotments made in
connection with the offering of the Firm Shares. If any Additional Shares are to
be purchased, each Underwriter agrees, severally and not jointly, to purchase
the number of Additional Shares (subject to such adjustments to eliminate
fractional shares as you may determine) that bears the same proportion to the
total number of Additional Shares to be purchased as the number of Firm Shares
set forth in Schedule A hereto opposite the name of such Underwriter bears to
the total number of Firm Shares.

           3.3   Market Standoff Provision. Each Seller hereby agrees that,
without the prior written consent of Thomas Weisel Partners, it will not, during
the period ending 180 days after the date of the Prospectus, (i) offer, pledge,
sell, contract to sell, sell any option or contract to purchase, purchase any
option or contract to sell, grant any option, right or warrant to purchase,
lend, or otherwise transfer or dispose of, directly or indirectly, any shares of
Common Stock or any securities convertible into or exercisable or exchangeable
for Common Stock or (ii) enter into any swap or other arrangement that transfers
to another, in whole or in part, any of the economic consequences of ownership
of the Common Stock, whether any such transaction described in clause (i) or
(ii) above is to be settled by delivery of Common Stock or such other
securities, in cash or otherwise. The foregoing sentence shall not apply to (A)
the Shares to be sold hereunder, (B) the issuance by the Company of shares of
Common Stock upon the exercise of options or

                                                                             -7-



warrants or the conversion of a security outstanding on the date hereof or under
the 2002 Employee Stock Purchase Plan, (C) the grant by the Company of options
to purchase shares of Common Stock, and the issuance of shares of Common Stock
upon the exercise of such options, pursuant to the Company's 1993 Stock Option
Plan, 1998 Stock Plan and 2002 Stock Plan, (D) transactions by any person other
than the Company relating to shares of Common Stock or other securities acquired
in open market transactions after the completion of the offering of the Shares
or (E) the issuance by the Company of Common Stock or securities convertible
into or exchangeable for Common Stock in connection with mergers or the
acquisition of securities, businesses, property or other assets, provided,
however, that any such issuance shall not amount to more than 3% of the
Company's outstanding Common Stock on the date of this Agreement. In addition,
each Selling Stockholder, agrees that, without the prior written consent of
Thomas Weisel Partners, it will not, during the period ending 180 days after the
date of the Prospectus, make any demand for, or exercise any right with respect
to, the registration of any shares of Common Stock or any security convertible
into or exercisable or exchangeable for Common Stock.

           3.4   Terms of Public Offering. The Sellers are advised by you that
the Underwriters propose to make a public offering of their respective portions
of the Shares as soon after the Registration Statement and this Agreement have
become effective as in your judgment is advisable. The Sellers are further
advised by you that the Shares are to be offered to the public initially at
$____ a share (the "Public Offering Price") and to certain dealers selected by
you at a price that represents a concession not in excess of $______ a share
under the Public Offering Price, and that any Underwriter may allow, and such
dealers may reallow, a concession, not in excess of $_____ a share, to any
Underwriter or to certain other dealers.

     4.    Payment and Delivery.

           4.1   Firm Shares. Payment for the Firm Shares to be sold by the
Company shall be made to the Company in immediately available funds against
delivery of such Firm Shares for the respective accounts of the several
Underwriters at 10:00 a.m., New York City time, on ____________, 2002, or at
such other time on the same or such other date, not later than _________, 2002,
as shall be designated in writing by you. The time and date of such payment are
hereinafter referred to as the "Closing Date."

           4.2   Additional Shares. Payment for any Additional Shares shall be
made to the Selling Stockholders in immediately available funds in New York City
against delivery of such Additional Shares for the respective accounts of the
several Underwriters at 10:00 a.m., New York City time, on the date specified in
the notice described in Section 3.2 or at such other time on the same or on such
other date, in any event not later than _______, 2002, as shall be designated in
writing by you. The time and date of such payment are hereinafter referred to as
the "Option Closing Date."

           4.3   Delivery of Certificates. Certificates for the Firm Shares and
Additional Shares shall be in definitive form and registered in such names and
in such denominations as you shall request in writing not later than one (1)
full business day prior to the Closing Date or the Option Closing Date, as the
case may be. The certificates evidencing the Firm Shares and Additional Shares
shall be delivered to you on the Closing Date or the Option Closing Date, as the
case may be, for the respective accounts of the several Underwriters, with any
transfer taxes payable in connection with the transfer of the Shares to the
Underwriters duly paid, against payment of the Purchase Price therefor.

     5.    Covenants of the Company. In further consideration of the agreements
of the Underwriters herein contained, the Company covenants with each
Underwriter as follows:

           5.1   Furnish Copies of Registration Statement and Prospectus. To
furnish to you, without charge, a signed copy of the Registration Statement
(including exhibits thereto) and for delivery to each other

                                                                             -8-



Underwriter a conformed copy of the Registration Statement (without exhibits
thereto) and to furnish to you in New York City, without charge, prior to 10:00
a.m. New York City time on the business day next succeeding the date of this
Agreement or as soon as commercially practicable and during the period mentioned
in Section 5.3 below, as many copies of the Prospectus and any supplements and
amendments thereto or to the Registration Statement as you may reasonably
request.

           5.2   Notification of Amendments or Supplements. Before amending or
supplementing the Registration Statement or the Prospectus, to furnish to you a
copy of each such proposed amendment or supplement and not to file any such
proposed amendment or supplement to which you reasonably object, and to file
with the Commission within the applicable period specified in Rule 424(b) under
the Securities Act any prospectus required to be filed pursuant to such rule.

           5.3   Filings of Amendments or Supplements. If, during such period
after the first date of the public offering of the Shares as in the opinion of
counsel for the Underwriters the Prospectus is required by law to be delivered
in connection with sales by an Underwriter or dealer (the "Prospectus Delivery
Period"), any event shall occur or condition exist as a result of which it is
necessary to amend or supplement the Prospectus in order to make the statements
therein, in the light of the circumstances when the Prospectus is delivered to a
purchaser, not misleading, or if, in the opinion of counsel for the
Underwriters, it is necessary to amend or supplement the Prospectus to comply
with applicable law, forthwith to prepare, file with the Commission and furnish,
at its own expense, to the Underwriters and to the dealers (whose names and
addresses you will furnish to the Company) to which Shares may have been sold by
you on behalf of the Underwriters and to any other dealers upon request, either
amendments or supplements to the Prospectus so that the statements in the
Prospectus as so amended or supplemented will not, in the light of the
circumstances when the Prospectus is delivered to a purchaser, be misleading or
so that the Prospectus, as amended or supplemented, will comply with law.

           5.4   Blue Sky Laws. To endeavor to qualify the Shares for offer and
sale under the securities or Blue Sky laws of such jurisdictions as you shall
reasonably request.

           5.5   Earnings Statement. To make generally available to its
securityholders as soon as practicable, but in any event not later than eighteen
(18) months after the effective date of the Registration Statement (as defined
in Rule 158(c) under the Securities Act), an earnings statement of the Company
and its subsidiaries (which need not be audited) complying with Section 11(a) of
the Securities Act and the rules and regulations thereunder (including, at the
option of the Company, Rule 158).

           5.6   Use of Proceeds. The Company shall apply the net proceeds from
the sale of the Shares sold by it in the manner described under the caption "Use
of Proceeds" in the Prospectus.

           5.7   Transfer Agent. The Company shall engage and maintain, at its
expense, a registrar and transfer agent for the Common Stock.

           5.8   Periodic Reporting Obligations. During the Prospectus Delivery
Period, the Company shall file, on a timely basis, with the Commission and the
Nasdaq National Market all reports and documents required to be filed under the
Exchange Act. Additionally, the Company shall file with the Commission such
information on Form 10-Q or Form 10-K as may be required by Rule 463 under the
Securities Act.

           5.9   Directed Share Program. That in connection with the Directed
Share Program, the Company will, upon notification, ensure that the Directed
Shares will be restricted to the extent required by the National Association of
Securities Dealers, Inc. (the "NASD") or the NASD rules from sale, transfer,

                                                                             -9-



assignment, pledge or hypothecation for a period of three (3) months following
the date of the effectiveness of the Registration Statement. Thomas Weisel
Partners will notify the Company as to which Participants will need to be so
restricted. The Company will direct the transfer agent to place stop transfer
restrictions upon such securities for such period of time. Furthermore, the
Company covenants with Thomas Weisel Partners that the Company will comply with
all applicable securities and other applicable laws, rules and regulations in
each foreign jurisdiction in which the Directed Shares are offered in connection
with the Directed Share Program.

           5.10  Exchange Act Compliance. During the Prospectus Delivery Period,
the Company will file all documents required to be filed with the Commission
pursuant to Section 13, 14 or 15 of the Exchange Age in the manner and within
the time periods required by the Exchange Act.

     6.    Conditions to the Underwriters' Obligations.  The obligations of the
Sellers to sell the Shares to the several Underwriters and the several
obligations of the Underwriters to purchase and pay for the Shares on the
Closing Date are subject to the following conditions:

           6.1   Effective Registration Statement. The Registration Statement
shall have become effective not later than __________, 2002 (New York City time)
on the date hereof.

           6.2   Rule 462 Registration Statement. If the Company elects to rely
upon Rule 462(b), the Company shall file a Rule 462 Registration Statement with
the Commission in compliance with Rule 462(b) by 10:00 P.M., Washington, D.C.
time, on the date of this Agreement, and the Company shall at the time of filing
either pay to the Commission the filing fee for the Rule 462 Registration
Statement or give irrevocable instructions for the payment of such fee pursuant
to Rule 111(b) under the Securities Act.

           6.3   Prospectus Filed with Commission. The Company shall have filed
the Prospectus with the Commission (including the information required by Rule
430A under the Securities Act) in the manner and within the time period required
by Rule 424(b) under the Securities Act; or the Company shall have filed a
post-effective amendment to the Registration Statement containing the
information required by such Rule 430A, and such post-effective amendment shall
have become effective.

           6.4   No Stop Order. No stop order suspending the effectiveness of
the Registration Statement, any Rule 462 Registration Statement, or any
post-effective amendment to the Registration Statement, shall be in effect and
no proceedings for such purpose shall have been instituted or threatened by the
Commission.

           6.5   No NASD Objection. The NASD shall have raised no objection to
the fairness and reasonableness of the underwriting terms and arrangements.

           6.6   No Debt Downgrading. There shall not have occurred any
downgrading, nor shall any notice have been given of any intended or potential
downgrading or of any review for a possible change that does not indicate the
direction of the possible change, in the rating accorded any of the Company's
securities by any "nationally recognized statistical rating organization," as
such term is defined for purposes of Rule 436(g)(2) under the Securities Act.

           6.7   No Material Adverse Change. There shall not have occurred any
change or any development involving a prospective change, in the condition,
financial or otherwise, or in the earnings, business or operations of the
Company and its subsidiaries, taken as a whole, from that set forth in the
Prospectus (exclusive of any amendments or supplements thereto subsequent to the
date of this Agreement)

                                                                            -10-



that, in your judgment, is material and adverse and that makes it, in your
judgment, impracticable to market the Shares on the terms and in the manner
contemplated in the Prospectus.

           6.8   Officer's Certificate. The Underwriters shall have received on
the Closing Date a certificate, dated the Closing Date and signed by the Chief
Executive Officer or President of the Company, to the effect set forth in
Sections 6.4 and 6.7 above and to the effect that the representations and
warranties of the Company contained in this Agreement are true and correct as of
the Closing Date (except that those representations and warranties which address
matters only as of a particular date shall remain true and correct as of such
date) and that the Company has complied in all material respects with all of the
agreements and satisfied all of the conditions on its part to be performed or
satisfied hereunder on or before the Closing Date.

           6.9   Opinion of Company Counsel. The Underwriters shall have
received on the Closing Date an opinion of Orrick, Herrington & Sutcliffe LLP,
counsel for the Company, dated the Closing Date, the form of which is attached
hereto as Exhibit A. The opinion shall be rendered to the Underwriters at the
request of the Company and shall so state therein.

           6.10  Opinion of Selling Stockholders Counsel. The Underwriters shall
have received on the Closing Date opinions of Orrick, Herrington & Sutcliffe LLP
and [Summit's counsel], counsels for the Selling Stockholders, dated the Closing
Date, the form of which is attached hereto as Exhibit B. The opinions shall be
rendered to the Underwriters at the request of the Selling Stockholders and
shall so state therein.

           6.11  Opinion of Underwriters Counsel. The Underwriters shall have
received on the Closing Date an opinion of Wilson Sonsini Goodrich & Rosati,
Professional Corporation, counsel for the Underwriters, dated the Closing Date,
covering the matters referred to in Exhibit A, paragraphs (vi), (vii), (ix) (but
only as to the statements in the Prospectus under "Description of Capital Stock"
and "Underwriters") and (xiii). With respect to paragraph (xiii) of Exhibit A,
such counsel may state that their opinion and belief are based upon their
participation in the preparation of the Registration Statement and Prospectus
and any amendments or supplements thereto and review and discussion of the
contents thereof, but are without independent check or verification, except as
specified.

           6.12  Accountant's Comfort Letter. The Underwriters shall have
received, on each of the date hereof and the Closing Date, a letter dated the
date hereof or the Closing Date, as the case may be, in form and substance
satisfactory to the Underwriters, from PricewaterhouseCoopers, LLP, independent
public accountants, containing statements and information of the type ordinarily
included in accountants' "comfort letters" to underwriters with respect to the
financial statements and certain financial information contained in the
Registration Statement and the Prospectus; provided that the letter delivered on
the Closing Date shall use a "cut-off date" not earlier than the date hereof.

           6.13  Lock-Up Agreements. The "lock-up" agreements, each
substantially in the form of Exhibit C hereto, between you and certain
stockholders, officers and directors of the Company, delivered to you on or
before the date hereof, shall be in full force and effect on the Closing Date.

           6.14  Selling Stockholders Certificate. The Underwriters shall have
received on the Option Closing Date a certificate, dated the Option Closing Date
and signed by the Attorney-in-Fact of each Selling Stockholder, to the effect
that the representations and warranties of the Selling Stockholders contained in
this Agreement are true and correct as of the Option Closing Date and that the
Selling Stockholders have complied in all material respects with all of the
agreements and satisfied all of the conditions on their part to be performed or
satisfied hereunder on or before the Option Closing Date.

                                                                            -11-



           6.15  Selling Stockholder Documents. On the date hereof, the Company
and the Selling Stockholders shall have furnished for review by the
Representatives copies of the Powers of Attorney and Custody Agreements executed
by each of the Selling Stockholders and such further information, certificates
and documents as the Representatives may reasonably request.

           6.16  Additional Documents. On the Closing Date, as applicable, the
Representatives and counsel for the Underwriters shall have received such
information, documents and opinions as they may reasonably require for the
purposes of enabling them to pass upon the issuance and sale of the Shares as
contemplated herein, or in order to evidence the accuracy of any of the
representations and warranties, or the satisfaction of any of the conditions or
agreements, herein contained.

     The several obligations of the Underwriters to purchase Additional Shares
hereunder are subject to the satisfaction of each of the above conditions on or
prior to the Option Closing Date and to the delivery to you on the Option
Closing Date of such documents as you may reasonably request with respect to the
good standing of the Company, the due authorization and issuance of the
Additional Shares and other matters related to the issuance of the Additional
Shares.

     7.    Expenses. Whether or not the transactions contemplated in this
Agreement are consummated or this Agreement is terminated, the Company agrees to
pay or cause to be paid all expenses incident to the performance of their
obligations under this Agreement, including: (i) the fees, disbursements and
expenses of the Company's counsel, the Company's accountants and counsel for the
Selling Stockholders in connection with the registration and delivery of the
Shares under the Securities Act and all other fees or expenses in connection
with the preparation and filing of the Registration Statement, any preliminary
prospectus, the Prospectus and amendments and supplements to any of the
foregoing, including all printing costs associated therewith, and the mailing
and delivering of copies thereof to the Underwriters and dealers, in the
quantities hereinabove specified, (ii) all reasonable costs and expenses related
to the transfer and delivery of the Shares to the Underwriters, including any
transfer or other taxes payable thereon, (iii) the cost of printing or producing
any Blue Sky or legal investment memorandum in connection with the offer and
sale of the Shares under state securities laws and all expenses in connection
with the qualification of the Shares for offer and sale under state securities
laws as contemplated by Section 5(d) hereof, including filing fees and the
reasonable fees and disbursements of counsel for the Underwriters in connection
with such qualification and in connection with the Blue Sky or legal investment
memorandum, (iv) all filing fees and the reasonable fees and disbursements of
counsel to the Underwriters incurred in connection with the review and
qualification of the offering of the Shares by the NASD, (v) all fees and
expenses in connection with the preparation and filing of the registration
statement on Form 8-A relating to the Common Stock and all costs and expenses
incident to listing the Shares on the Nasdaq National Market, (vi) the cost of
printing certificates representing the Shares, (vii) the costs and charges of
any transfer agent, registrar or depositary, (viii) the costs and expenses of
the Company relating to investor presentations on any "road show" undertaken in
connection with the marketing of the offering of the Shares, including, without
limitation, expenses associated with the production of road show slides and
graphics, fees and expenses of any consultants engaged in connection with the
road show presentations with the prior approval of the Company, travel and
lodging expenses of the representatives and officers of the Company and any such
consultants, and the Company's proportionate cost of any aircraft chartered in
connection with the road show, (ix) all expenses in connection with any offer
and sale of the Shares outside of the United States, including filing fees and
the reasonable fees and disbursements of counsel for the Underwriters in
connection with offers and sales outside of the United States, (x) all
reasonable fees and disbursements of counsel incurred by the Underwriters in
connection with the Directed Share Program and stamp duties, similar taxes or
duties or other taxes, if any, incurred by the Underwriters in connection with
the Directed Share Program, and (xi) all other costs and expenses incident to
the performance of the obligations of the Company hereunder for which provision
is not otherwise made in this Section. It is understood, however, that except as
provided in this Section, Section 8 entitled "Indemnity and Contribution,"

                                                                            -12-



and the last paragraph of Section 11 below, the Underwriters will pay all of
their costs and expenses, including fees and disbursements of their counsel and
any advertising expenses connected with any offers they may make.

     The provisions of this Section shall not supersede or otherwise affect any
agreement that the Sellers may otherwise have for the allocation of such
expenses among themselves.

     8.    Indemnity and Contribution.

           8.1   Indemnification of the Underwriters by the Company. The Company
agrees to indemnify and hold harmless each Underwriter and each person, if any,
who controls any Underwriter within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act, from and against any and all
losses, claims, damages and liabilities (including, without limitation, any
legal or other expenses reasonably incurred in connection with defending or
investigating any such action or claim) caused by any untrue statement or
alleged untrue statement of a material fact contained in the Registration
Statement or any amendment thereof, any preliminary prospectus or the Prospectus
(as amended or supplemented if the Company shall have furnished any amendments
or supplements thereto), or caused by any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, except (i) insofar as such losses, claims,
damages or liabilities are caused by any such untrue statement or omission or
alleged untrue statement or omission based upon information relating to any
Underwriter furnished to the Company in writing by such Underwriter through you
expressly for use therein and (ii) that with respect to any preliminary
prospectus, the foregoing indemnity agreement shall not inure to the benefit of
any Underwriter from whom the person asserting any loss, claim, damage or
liability purchased Shares, or any person controlling such Underwriter, if
copies of the Prospectus were timely delivered to the Underwriter pursuant to
Section 5 and a copy of the Prospectus (as then amended or supplemented if the
Company shall have furnished any amendments or supplements thereto) was not sent
or given by or on behalf of such Underwriter to such person, if required by law
so to have been delivered, at or prior to the written confirmation of the sale
of the Shares to such person, and if the Prospectus (as so amended or
supplemented) would have cured the defect giving rise to such loss, claim,
damage, liability or expense.

           8.2   Indemnification of Company by the Selling Stockholders. Each
Selling Stockholder agrees, severally and not jointly, to indemnify and hold
harmless the Company, its directors, its officers who sign the Registration
Statement and each person, if any, who controls the Company within the meaning
of either Section 15 of the Securities Act or Section 20 of the Exchange Act,
from and against any and all losses, claims, damages and liabilities (including,
without limitation, any legal or other expenses reasonably incurred in
connection with defending or investigating any such action or claim) caused by
any untrue statement or alleged untrue statement of a material fact contained in
the Registration Statement or any amendment thereof, any preliminary prospectus
or the Prospectus (as amended or supplemented if the Company shall have
furnished any amendments or supplements thereto), or caused by any omission or
alleged omission to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, but only with
reference to information relating to such Selling Stockholder furnished in
writing by or on behalf of such Selling Stockholder expressly for use in the
Registration Statement, any preliminary prospectus, the Prospectus or any
amendments or supplements thereto.

           8.3   Indemnification of Underwriters by Selling Stockholders.

                 (a) Each Selling Stockholder agrees, severally and not jointly,
to indemnify and hold harmless each Underwriter and each person, if any, who
controls any Underwriter within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act, from and against any and all
losses, claims, damages and liabilities (including, without limitation, any
legal or other expenses reasonably incurred

                                                                            -13-



in connection with defending or investigating any such action or claim) caused
by any untrue statement or alleged untrue statement of a material fact contained
in the Registration Statement or any amendment thereof, any preliminary
prospectus or the Prospectus (as amended or supplemented if the Company shall
have furnished any amendments or supplements thereto), or caused by any omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, but only
with reference to information relating to such Selling Stockholder furnished in
writing by or on behalf of such Selling Stockholder expressly for use in the
Registration Statement, any preliminary prospectus, the Prospectus or any
amendments or supplements thereto.

                 (b) In the event that any Underwriter or any person, if any,
who controls any Underwriter within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act shall have properly made any
request for indemnification pursuant to Section 8.1 and the Company (i) shall
have failed to pay such amount or otherwise failed to satisfy its obligations
set forth in Section 8.1 within 30 days of such request, or (ii) shall be, in
such indemnified party's reasonable judgment, unable or unwilling to satisfy
such obligations, each Selling Officer shall, severally and not jointly,
promptly indemnify and hold harmless such indemnified party to the same extent
as the Company shall be required to indemnify such indemnified party, or shall
contribute to the amount paid or payable by such indemnified party to the same
extent as the Company shall be required to contribute to such amount in the
event indemnification is unavailable or is insufficient as contemplated by
Section 8.8 or 8.9.

           8.4   Indemnification by the Underwriters. Each Underwriter agrees,
severally and not jointly, to indemnify and hold harmless the Company, the
Selling Stockholders, the directors of the Company, the officers of the Company
who sign the Registration Statement and each person, if any, who controls the
Company or any Selling Stockholder within the meaning of either Section 15 of
the Securities Act or Section 20 of the Exchange Act from and against any and
all losses, claims, damages and liabilities (including, without limitation, any
legal or other expenses reasonably incurred in connection with defending or
investigating any such action or claim) caused by any untrue statement or
alleged untrue statement of a material fact contained in the Registration
Statement or any amendment thereof, any preliminary prospectus or the Prospectus
(as amended or supplemented if the Company shall have furnished any amendments
or supplements thereto), or caused by any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, but only with reference to information
relating to such Underwriter furnished to the Company in writing by such
Underwriter through you expressly for use in the Registration Statement, any
preliminary prospectus, the Prospectus or any amendments or supplements thereto.

           8.5   Indemnification Procedures. In case any proceeding (including
any governmental investigation) shall be instituted involving any person in
respect of which indemnity may be sought pursuant to this Section 8, such person
(the "indemnified party") shall promptly notify the person against whom such
indemnity may be sought (the "indemnifying party") in writing and the
indemnifying party, upon request of the indemnified party, shall retain counsel
reasonably satisfactory to the indemnified party to represent the indemnified
party and any others the indemnifying party may designate in such proceeding and
shall pay the fees and disbursements of such counsel related to such proceeding.
In any such proceeding, any indemnified party shall have the right to retain its
own counsel, but the fees and expenses of such counsel shall be at the expense
of such indemnified party unless (i) the indemnifying party and the indemnified
party shall have mutually agreed to the retention of such counsel or (ii) the
named parties to any such proceeding (including any impleaded parties) include
both the indemnifying party and the indemnified party and representation of both
parties by the same counsel would be inappropriate due to actual or potential
differing interests between them. It is understood that the indemnifying party
shall not, in respect of the legal expenses of any indemnified party in
connection with any proceeding or related proceedings in the same jurisdiction,
be liable for (i) the fees and expenses of more than one separate firm (in
addition to any local counsel) for all

                                                                            -14-



Underwriters and all persons, if any, who control any Underwriter within the
meaning of either Section 15 of the Securities Act or Section 20 of the Exchange
Act, (ii) the fees and expenses of more than one separate firm (in addition to
any local counsel) for the Company, its directors, its officers who sign the
Registration Statement and each person, if any, who controls the Company within
the meaning of either such Section and (iii) the fees and expenses of more than
one separate firm (in addition to any local counsel) for all Selling
Stockholders and all persons, if any, who control any Selling Stockholder within
the meaning of either such Section, and that all such fees and expenses shall be
reimbursed as they are incurred. In the case of any such separate firm for the
Underwriters and such control persons of any Underwriters, such firm shall be
designated in writing by Thomas Weisel Partners. In the case of any such
separate firm for the Company, and such directors, officers and control persons
of the Company, such firm shall be designated in writing by the Company. In the
case of any such separate firm for the Selling Stockholders and such control
persons of any Selling Stockholders, such firm shall be designated in writing by
the persons named as attorneys-in-fact for the Selling Stockholders under the
Powers of Attorney. The indemnifying party shall not be liable for any
settlement of any proceeding effected without its written consent, but if
settled with such consent or if there be a final judgment for the plaintiff, the
indemnifying party agrees to indemnify the indemnified party from and against
any loss or liability by reason of such settlement or judgment. Notwithstanding
the foregoing sentence, if at any time an indemnified party shall have requested
an indemnifying party to reimburse the indemnified party for fees and expenses
of counsel as contemplated by the second and third sentences of this paragraph,
the indemnifying party agrees that it shall be liable for any settlement of any
proceeding effected without its written consent if (i) such settlement is
entered into more than 60 days after receipt by such indemnifying party of the
aforesaid request and (ii) such indemnifying party shall not have reimbursed the
indemnified party in accordance with such request prior to the date of such
settlement. No indemnifying party shall, without the prior written consent of
the indemnified party, effect any settlement of any pending or threatened
proceeding in respect of which any indemnified party is or could have been a
party and indemnity could have been sought hereunder by such indemnified party,
unless such settlement includes an unconditional release of such indemnified
party from all liability on claims that are the subject matter of such
proceeding.

           8.6   Limitation of Selling Stockholder Liability. Notwithstanding
anything herein to the contrary, the liability of each Selling Stockholder under
the indemnity and contribution provisions of this Section 8 and the
representation in Section 2.9 shall be limited to an amount equal to the initial
public offering price of the Shares sold by such Selling Stockholder, less the
underwriting discount, as set forth on the front cover page of the Prospectus.
The Company and the Selling Stockholders may agree, as among themselves and
without limiting the rights of the Underwriters under this Agreement, as to the
respective amounts of such liability for which they each shall be responsible.

           8.7   Indemnification for Directed Share Program. The Company agrees
to indemnify and hold harmless Thomas Weisel Partners and each person, if any,
who controls Thomas Weisel Partners within the meaning of either Section 15 of
the Securities Act or Section 20 of the Exchange Act ("Thomas Weisel Partners
Entities"), from and against any and all losses, claims, damages and liabilities
(including, without limitation, any legal or other expenses reasonably incurred
in connection with defending or investigating any such action or claim) (i)
caused by any untrue statement or alleged untrue statement of a material fact
contained in the prospectus wrapper material prepared by or with the consent of
the Company for distribution in foreign jurisdictions in connection with the
Directed Share Program attached to the Prospectus or any preliminary prospectus,
or caused by any omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statement therein, when
considered in conjunction with the Prospectus or any applicable preliminary
prospectus, not misleading; (ii) caused by the failure of any Participant to pay
for and accept delivery of the shares which, immediately following the
effectiveness of the Registration Statement, were subject to a properly
confirmed agreement to purchase; or (iii) related to, arising out of, or in
connection with the Directed Share Program, provided that, the Company shall not
be responsible

                                                                            -15-



 under this subparagraph (iii) for any losses, claim, damages or liabilities
(or expenses relating thereto) that are finally judicially determined to have
resulted from the bad faith or gross negligence of Thomas Weisel Partners
Entities.

           8.8   Contribution Agreement. To the extent the indemnification
provided for in this Section 8 is unavailable to an indemnified party or
insufficient in respect of any losses, claims, damages or liabilities referred
to therein, then each indemnifying party under such paragraph, in lieu of
indemnifying such indemnified party thereunder, shall contribute to the amount
paid or payable by such indemnified party as a result of such losses, claims,
damages or liabilities (i) in such proportion as is appropriate to reflect the
relative benefits received by the indemnifying party or parties on the one hand
and the indemnified party or parties on the other hand from the offering of the
Shares or (ii) if the allocation provided by clause 8(g) above is not permitted
by applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in Section 8.5 above but also the relative fault
of the indemnifying party or parties on the one hand and of the indemnified
party or parties on the other hand in connection with the statements or
omissions that resulted in such losses, claims, damages or liabilities, as well
as any other relevant equitable considerations. The relative benefits received
by the Sellers on the one hand and the Underwriters on the other hand in
connection with the offering of the Shares shall be deemed to be in the same
respective proportions as the net proceeds from the offering of the Shares
(before deducting expenses) received by each Seller and the total underwriting
discounts and commissions received by the Underwriters, in each case as set
forth in the table on the cover of the Prospectus, bear to the aggregate Public
Offering Price of the Shares. The relative fault of the Sellers on the one hand
and the Underwriters on the other hand shall be determined by reference to,
among other things, whether the untrue or alleged untrue statement of a material
fact or the omission or alleged omission to state a material fact relates to
information supplied by the Sellers or by the Underwriters and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission. The Underwriters' respective obligations to
contribute pursuant to this Section 8 are several in proportion to the
respective number of Shares they have purchased hereunder, and not joint.

           8.9   Contribution Amounts. The Sellers and the Underwriters agree
that it would not be just or equitable if contribution pursuant to this Section
8 were determined by pro rata allocation (even if the Underwriters were treated
as one entity for such purpose) or by any other method of allocation that does
not take account of the equitable considerations referred to in Section 8.8. The
amount paid or payable by an indemnified party as a result of the losses,
claims, damages and liabilities referred to in the immediately preceding
paragraph shall be deemed to include, subject to the limitations set forth
above, any legal or other expenses reasonably incurred by such indemnified party
in connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 8, no Underwriter shall be
required to contribute any amount in excess of the amount by which the total
price at which the Shares underwritten by it and distributed to the public were
offered to the public exceeds the amount of any damages that such Underwriter
has otherwise been required to pay by reason of such untrue or alleged untrue
statement or omission or alleged omission. No person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation. The remedies provided for in this Section 8 are
not exclusive and shall not limit any rights or remedies which may otherwise be
available to any indemnified party at law or in equity; subject to the liability
limitations of the Selling Stockholders set forth in Section 8.6.

           8.10  Survival of Provisions. The indemnity and contribution
provisions contained in this Section 8 and the representations, warranties and
other statements of the Company and the Selling Stockholders contained in this
Agreement shall remain operative and in full force and effect regardless of (i)
any termination of this Agreement, (ii) any investigation made by or on behalf
of any Underwriter or any person controlling any Underwriter, any Selling
Stockholder or any person controlling any Selling

                                                                            -16-



Stockholder, or the Company, its officers or directors or any person controlling
the Company and (iii) acceptance of and payment for any of the Shares.

     9.    Effectiveness. This Agreement shall become effective upon the
execution and delivery hereof by the parties hereto.

     10.   Termination. This Agreement shall be subject to termination by notice
given by you to the Company, if (a) after the execution and delivery of this
Agreement and prior to the Closing Date (i) trading generally shall have been
suspended or materially limited on or by, as the case may be, any of the New
York Stock Exchange, the American Stock Exchange, the National Association of
Securities Dealers, Inc., the Chicago Board of Options Exchange, the Chicago
Mercantile Exchange or the Chicago Board of Trade, (ii) trading of any
securities of the Company shall have been suspended on any exchange or in any
over-the-counter market, (iii) a general moratorium on commercial banking
activities in New York, Delaware or California shall have been declared by
either federal or New York, Delaware or California state authorities or (iv)
there shall have occurred any outbreak or escalation of hostilities or any
change in financial markets or any calamity or crisis that, in your reasonable
judgment, is material and adverse, or (v) in the reasonable judgment of the
Representatives, there shall have occurred any material adverse change, or any
development that could reasonably be expected to result in a material adverse
change, in the condition, financial or otherwise, or in the earnings, business,
operations or prospects, whether or not arising from transactions in the
ordinary course of business, of the Company and its subsidiaries, taken as a
whole, and (b) in the case of any of the events specified in clauses 10(a)(i)
through 10(a)(v), such event, individually or together with any other such
event, makes it, in your reasonable judgment, impracticable to market the Shares
on the terms and in the manner contemplated in the Prospectus.

     11.   Defaulting Underwriters. If, on the Closing Date or the Option
Closing Date, as the case may be, any one or more of the Underwriters shall fail
or refuse to purchase Shares that it has or they have agreed to purchase
hereunder on such date, and the aggregate number of Shares which such defaulting
Underwriter or Underwriters agreed but failed or refused to purchase is not more
than one-tenth of the aggregate number of the Shares to be purchased on such
date, the other Underwriters shall be obligated severally in the proportions
that the number of Firm Shares set forth opposite their respective names in
Schedule A bears to the aggregate number of Firm Shares set forth opposite the
names of all such non-defaulting Underwriters, or in such other proportions as
you may specify, to purchase the Shares which such defaulting Underwriter or
Underwriters agreed but failed or refused to purchase on such date; provided
that in no event shall the number of Shares that any Underwriter has agreed to
purchase pursuant to this Agreement be increased pursuant to this Section 11 by
an amount in excess of one-ninth of such number of Shares without the written
consent of such Underwriter. If, on the Closing Date, any Underwriter or
Underwriters shall fail or refuse to purchase Firm Shares and the aggregate
number of Firm Shares with respect to which such default occurs is more than
one-tenth of the aggregate number of Firm Shares to be purchased, and
arrangements satisfactory to you, the Company and the Selling Stockholders for
the purchase of such Firm Shares are not made within 36 hours after such
default, this Agreement shall terminate without liability on the part of any
non-defaulting Underwriter, the Company or the Selling Stockholders. In any such
case either you or the relevant Sellers shall have the right to postpone the
Closing Date, but in no event for longer than seven (7) days, in order that the
required changes, if any, in the Registration Statement and in the Prospectus or
in any other documents or arrangements may be effected. If, on the Option
Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase
Additional Shares and the aggregate number of Additional Shares with respect to
which such default occurs is more than one-tenth of the aggregate number of
Additional Shares to be purchased, the non-defaulting Underwriters shall have
the option to (i) terminate their obligation hereunder to purchase Additional
Shares or (ii) purchase not less than the number of Additional Shares that such
non-defaulting Underwriters would have been obligated to purchase in the absence
of such default. Any action taken under

                                                                            -17-



this paragraph shall not relieve any defaulting Underwriter from liability in
respect of any default of such Underwriter under this Agreement.

     If this Agreement shall be terminated by the Underwriters, or any of them,
because of any failure or refusal on the part of any Seller to comply with the
terms or to fulfill any of the conditions of this Agreement, or if for any
reason any Seller shall be unable to perform its obligations under this
Agreement, the Sellers will reimburse the Underwriters or such Underwriters as
have so terminated this Agreement with respect to themselves, severally, for all
out-of-pocket expenses (including the fees and disbursements of their counsel)
reasonably incurred by such Underwriters in connection with this Agreement or
the offering contemplated hereunder.

     12.   Counterparts. This Agreement may be signed in counterparts, each of
which shall be an original, with the same effect as if the signatures thereto
and hereto were upon the same instrument.

     13.   Headings; Table of Contents. The headings of the sections of this
Agreement and the table of contents have been inserted for convenience of
reference only and shall not be deemed a part of this Agreement.

     14.   Notices. All communications hereunder shall be in writing and shall
be mailed, hand delivered or telecopied and confirmed to the parties hereto as
follows:

           If to the Representatives:

           Thomas Weisel Partners LLC
           One Montgomery Street, Suite 3700
           San Francisco, California 94104
           Facsimile: (212) 271-3748
           Attention: James Streator

           with a copy to:

           Thomas Weisel Partners LLC
           One Montgomery Street, Suite 3700
           San Francisco, California 94104
           Facsimile: (415) 364-2694
           Attention: David A. Baylor, Esq.

           If to the Company:

           IMPAC Medical Systems, Inc.
           100 West Evelyn Avenue
           Mountain View, California 94041
           Facsimile:  650-623-8915
           Attention:  Joseph Jachinowski

           with a copy to:
           Orrick, Herrington & Sutcliffe LLP
           400 Sansome Street
           San Francisco, California 94111
           Facsimile: (415) 773-5759

                                                                            -18-



               Attention:  Alan Talkington, Esq.

               If to the Selling Stockholders:

               [Custodian]
               [address]
               Facsimile:  [___________]
               Attention:  [___________]

               with copies to:

               Orrick, Herrington & Sutcliffe LLP
               400 Sansome Street
               San Francisco, California 94111
               Facsimile:  (415) 773-5759
               Attention:  Alan Talkington, Esq.; and

               [Summit's Counsel]

               [address]
               Facsimile:  [___________]
               Attention:  [___________]

     Any party hereto may change the address for receipt of communications by
giving written notice to the others.

     15.   Successors. This Agreement will inure to the benefit of and be
binding upon the parties hereto, including any substitute Underwriters pursuant
to Section 11 hereof, and to the benefit of the officers and directors and
controlling persons referred to in Section 8, and in each case their respective
successors, and no other person will have any right or obligation hereunder. The
term "successors" shall not include any purchaser of the Shares as such from any
of the Underwriters merely by reason of such purchase.

     16.   Partial Unenforceability. The invalidity or unenforceability of any
Section, paragraph or provision of this Agreement shall not affect the validity
or enforceability of any other Section, paragraph or provision hereof. If any
Section, paragraph or provision of this Agreement is for any reason determined
to be invalid or unenforceable, there shall be deemed to be made such minor
changes (and only such minor changes) as are necessary to make it valid and
enforceable.

     17.   Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK APPLICABLE TO
AGREEMENTS MADE AND TO BE PERFORMED IN SUCH STATE.

     18.   Consent to Jurisdiction. Any legal suit, action or proceeding arising
out of or based upon this Agreement or the transactions contemplated hereby
("Related Proceedings") may be instituted in the federal courts of the United
States of America located in the City and County of San Francisco or the courts
of the State of California in each case located in the City and County of San
Francisco (collectively, the "Specified Courts"), and each party irrevocably
submits to the exclusive jurisdiction (except for proceedings instituted in
regard to the enforcement of a judgment of any such court (a "Related
Judgment"), as to which such jurisdiction is non-exclusive) of such courts in
any such suit, action or proceeding. Service of any process, summons, notice or
document by mail to such party's address set forth above shall be effective
service of

                                                                            -19-



process for any suit, action or other proceeding brought in any such court. The
parties irrevocably and unconditionally waive any objection to the laying of
venue of any suit, action or other proceeding in the Specified Courts and
irrevocably and unconditionally waive and agree not to plead or claim in any
such court that any such suit, action or other proceeding brought in any such
court has been brought in an inconvenient forum.

     19.  Waiver of Immunity. With respect to any Related Proceeding, each party
irrevocably waives, to the fullest extent permitted by applicable law, all
immunity (whether on the basis of sovereignty or otherwise) from jurisdiction,
service of process, attachment (both before and after judgment) and execution to
which it might otherwise be entitled in the Specified Courts, and with respect
to any Related Judgment, each party waives any such immunity in the Specified
Courts or any other court of competent jurisdiction, and will not raise or claim
or cause to be pleaded any such immunity at or in respect of any such Related
Proceeding or Related Judgment, including, without limitation, any immunity
pursuant to the United States Foreign Sovereign Immunities Act of 1976, as
amended.

     20.  Failure of the Selling Stockholders to Sell and Deliver Shares. If one
or more of the Selling Stockholders shall fail to sell and deliver to the
Underwriters the Shares to be sold and delivered by such Selling Stockholders at
the Option Closing Date pursuant to this Agreement, then the Underwriters may at
their option, by written notice from the Representatives to the Company and the
Selling Stockholders, either (i) terminate this Agreement without any liability
on the part of any Underwriter or, except as provided in Sections 7 and 8
hereof, the Company or the Selling Stockholders, or (ii) purchase the shares
which the Company and other Selling Stockholders have agreed to sell and deliver
in accordance with the terms hereof. If one or more of the Selling Stockholders
shall fail to sell and deliver to the Underwriters the Shares to be sold and
delivered by such Selling Stockholders pursuant to this Agreement at the Option
Closing Date, then the Underwriters shall have the right, by written notice from
the Representatives to the Company and the Selling Stockholders, to postpone the
Option Closing Date, but in no event for longer than seven (7) days in order
that the required changes, if any, to the Registration Statement and the
Prospectus or any other documents or arrangements may be effected.

     21.  Entire Agreement. This Agreement constitutes the entire agreement of
the parties to this Agreement and supersedes all prior written or oral and all
contemporaneous oral agreements, understandings and negotiations with respect to
the subject matter hereof.

     22.  Amendments. This Agreement may only be amended or modified in writing,
signed by all of the parties hereto, and no condition herein (express or
implied) may be waived unless waived in writing by each party whom the condition
is meant to benefit.

     23.  Sophisticated Parties. Each of the parties hereto acknowledges that it
is a sophisticated business person who was adequately represented by counsel
during negotiations regarding the provisions hereof, including, without
limitation, the indemnification and contribution provisions of Section 8, and is
fully informed regarding said provisions. Each of the parties hereto further
acknowledges that the provisions of Section 8 hereto fairly allocate the risks
in light of the ability of the parties to investigate the Company, its affairs
and its business in order to assure that adequate disclosure has been made in
the Registration Statement, any preliminary prospectus and the Prospectus (and
any amendments and supplements thereto), as required by the Securities Act and
the Exchange Act.

                  [Remainder of page intentionally left blank]

                                                                            -20-



     If the foregoing is in accordance with your understanding of our agreement,
kindly sign and return to the Company the enclosed copies hereof, whereupon this
instrument, along with all counterparts hereof, shall become a binding agreement
in accordance with its terms.

                                    Very truly yours,

                                    IMPAC Medical Systems, Inc.


                                    By:_________________________________________
                                    Name: Joseph K. Jachinowski
                                    Title: President and Chief Executive Officer

                                    The Selling Stockholders
                                    named in Schedule B hereto,
                                    acting severally

                                    By:_________________________________________
                                         Attorney-in-Fact

Accepted as of the date hereof

Thomas Weisel Partners LLC
U.S. Bancorp Piper Jaffray
SG Cowen Securities Corporation

Acting severally on behalf
  of themselves and the
  several Underwriters named
  in Schedule A hereto.

By:   Thomas Weisel Partners LLC


By:__________________________________
Name:
Title:

                                                                            -21-




                                   SCHEDULE A

                                                                    Number of
              Underwriter                                          Firm Shares
                                                                 To Be Purchased

Thomas Weisel Partners LLC
U.S. Bancorp Piper Jaffray
SG Cowen Securities Corporation
[NAMES OF OTHER UNDERWRITERS]

                Total



                                   SCHEDULE B

                                                                    Number of
              Selling Stockholder                              Additional Shares
                                                                   To Be Sold

[NAMES OF SELLING SHAREHOLDERS]

                      Total



                                    EXHIBIT A

                    Form of Legal Opinion of Company Counsel

     i.     The Company has been duly incorporated, is validly existing as a
corporation in good standing under the laws of the State of Delaware, has the
corporate power and authority to own its property and to conduct its business as
described in the Prospectus and is duly qualified to transact business and is in
good standing in each jurisdiction in which the conduct of its business or its
ownership or leasing of property requires such qualification, except to the
extent that the failure to be so qualified or be in good standing would not have
a material adverse effect on the Company and its subsidiaries, taken as a whole.

     ii.    IMPAC Global Systems, Inc. has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the State of
Delaware, has the corporate power and authority to own its property and to
conduct its business as described in the Prospectus and is duly qualified to
transact business and is in good standing in each jurisdiction in which the
conduct of its business or its ownership or leasing of property requires such
qualification, except to the extent that the failure to be so qualified or be in
good standing would not have a material adverse effect on the Company and its
subsidiaries, taken as a whole.

     iii.   All of the issued shares of capital stock of IMPAC Global Systems,
Inc. have been duly and validly authorized and issued, are fully paid and
non-assessable and are owned directly by the Company.

     iv.    The shares of Common Stock outstanding prior to the issuance of the
Shares to be sold by the Company have been duly authorized and are validly
issued, fully paid and non-assessable.

     v.     The Shares to be sold by the Company have been duly authorized and,
when issued and delivered in accordance with the terms of the Underwriting
Agreement, will be validly issued, fully paid and non-assessable, and, to such
counsel's knowledge, the issuance of such Shares will not be subject to any
preemptive or similar rights.

     vi.    The Underwriting Agreement has been duly authorized, executed and
delivered by the Company.

     vii.   The execution and delivery by the Company of, and the performance by
the Company of its obligations under, the Underwriting Agreement will not
contravene any provision of applicable law or the certificate of incorporation
or by-laws of the Company or, to the best of such counsel's knowledge, any
agreement or other instrument binding upon the Company or any of its
subsidiaries that that has been filed as an exhibit to the Registration
Statement, or, to the best of such counsel's knowledge, any judgment, order or
decree of any governmental body, agency or court having jurisdiction over the
Company or any subsidiary, and no consent, approval, authorization or order of,
or qualification with, any governmental body or agency is required for the
performance by the Company of its obligations under this Agreement, except such
as (a) have been obtained under the Securities Act, (b) may be required by the
securities or Blue Sky laws of the various states in connection with the offer
and sale of the Shares or (c) may be required by the NASD, in each case as to
which such counsel need express no opinion.

     viii.  The statements (A) in the Prospectus under the captions
"Management--Stock Plans," "Management--Indemnification," "Description of
Capital Stock" and "Underwriting" and (B) in the Registration Statement in Items
14 and 15, in each case insofar as such statements constitute summaries of the
legal matters, documents or proceedings referred to therein, fairly present the
information called for with respect to such legal matters, documents and
proceedings and fairly summarize the matters referred to therein.



     ix.  To such counsel's knowledge, there are no (A) legal or governmental
proceedings pending or threatened to which the Company or any of its
subsidiaries is a party or to which any of the properties of the Company or any
of its subsidiaries is subject that are required to be described in the
Registration Statement or the Prospectus and are not so described, or (B) any
statutes, regulations, contracts or other documents that are required to be
described in the Registration Statement or the Prospectus or to be filed as
exhibits to the Registration Statement that are not described or filed as
required (except as to regulatory matters as to which such counsel need not
express any opinion).

     x.   The Company is not and, after giving effect to the offering and sale
of the Shares and the application of the proceeds thereof as described in the
Prospectus, will not be an "investment company" as such term is defined in the
Investment Company Act of 1940, as amended.

     xi.  The Registration Statement and Prospectus (except for financial
statements and schedules and other financial and statistical data included
therein as to which such counsel need not express any opinion) comply as to form
in all material respects with the Securities Act and the applicable rules and
regulations of the Commission thereunder.

     In connection with the preparation of the Registration Statement and the
Prospectus, such counsel has participated in conferences with officers and other
representatives of the Company and with its certified public accountants, as
well as with representatives of the Underwriters and their counsel. At such
conferences, the contents of the Registration Statement and the Prospectus and
related matters were discussed. Such counsel has not independently verified and
accordingly is not confirming and assumes no responsibility for the accuracy or
completeness of the statements contained in the Registration Statement or the
Prospectus. On the basis of the foregoing, nothing has come to such counsel's
attention that has caused such counsel to believe (i) that the Registration
Statement (except as to the financial statements and schedules, related notes
and other financial data and statistical data derived therefrom, as to which
counsel need not express any belief) at the Effective Date contained any untrue
statement of a material fact or omitted to state a material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, or (ii) that the
Prospectus (except as to the financial statements and schedules, related notes
and other financial data and statistical data derived therefrom, as to which
counsel need not express any belief) as of its date or at the Closing Date,
contained or contains any untrue statement of a material fact or omitted or
omits to state a material fact necessary, in order to make the statements
therein, in light of the circumstances under which they were made, not
misleading.

                                                                             -2-



                                    EXHIBIT B

              Form of Legal Opinion of Selling Stockholders Counsel

     i.    The Underwriting Agreement has been duly authorized, executed and
delivered by or on behalf of each of the Selling Stockholders.

     ii.   The execution and delivery by each Selling Stockholder of, and the
performance by such Selling Stockholder of its obligations under, the
Underwriting Agreement and the Custody Agreement and Powers of Attorney of such
Selling Stockholder will not contravene any provision of applicable law, or the
[certificate] of incorporation or by-laws of such Selling Stockholder (if such
Selling Stockholder is a corporation), or, to such counsel's knowledge, any
agreement or other instrument binding upon such Selling Stockholder or, to such
counsel's knowledge, any judgment, order or decree of any governmental body,
agency or court having jurisdiction over such Selling Stockholder, and no
consent, approval, authorization or order of, or qualification with, any
governmental body or agency is required for the performance by such Selling
Stockholder of its obligations under the Underwriting Agreement or the Custody
Agreement or Power of Attorney of such Selling Stockholder, except such as (a)
have been obtained under the Securities Act, (b) may be required by the
securities or Blue Sky laws of the various states in connection with the offer
and sale of the Shares or (c) may be required by the NASD, in each case as to
which such counsel need express no opinion.

     iii.  The Custody Agreement and the Power of Attorney of each Selling
Stockholder have been duly authorized, executed and delivered by such Selling
Stockholder and are valid and binding agreements of such Selling Stockholder.

     Such counsel may rely with respect to factual matters and to the extent
such counsel deems appropriate, upon the representations of each Selling
Stockholder contained in the Underwriting Agreement and in the Custody Agreement
and Power of Attorney of such Selling Stockholder and in other documents and
instruments; provided that copies of such Custody Agreements and Powers of
Attorney and of any such other documents and instruments shall be delivered to
counsel to the Underwriters and shall be in form and substance satisfactory to
counsel to the Underwriters.



                                    EXHIBIT C

                            FORM OF LOCK-UP AGREEMENT

                                                                     May 9, 2002
Thomas Weisel Partners LLC
U.S. Bancorp Piper Jaffray
SG Cowen Securities Corporation
as Representatives of the several Underwriters
c/o Thomas Weisel Partners LLC
One Montgomery Street, Suite 3700
San Francisco, California 94104

                     Re: Lock-Up Agreement (the "Agreement")

Ladies and Gentlemen:

     The undersigned is an owner of record or beneficially of certain shares of
Common Stock, par value $0.0001 per share (the "Common Stock"), of IMPAC Medical
Systems, Inc., a California corporation (the "Company"), or securities
convertible into or exchangeable or exercisable for Common Stock. The
undersigned understands that you, as representatives (the "Representatives"),
propose to enter into an Underwriting Agreement on behalf of the several
Underwriters named in Schedule A to such agreement (collectively, the
"Underwriters"), with the Company providing for a public offering of the Common
Stock of the Company pursuant to a Registration Statement on Form S-1 to be
filed with the Securities and Exchange Commission (the "Public Offering"). The
undersigned recognizes that the Public Offering will be of benefit to the
undersigned and will benefit the Company by, among other things, raising
additional capital for its operations. The undersigned acknowledges that you and
the other Underwriters are relying on the representations and agreements of the
undersigned contained in this letter in carrying out the Public Offering and in
entering into underwriting arrangements with the Company with respect to the
Public Offering.

     To induce the Underwriters that may participate in the Public Offering to
continue their efforts in connection with the Public Offering, the undersigned
hereby agrees that, without the prior written consent of Thomas Weisel Partners
(which consent may be withheld in its sole discretion), it will not, during the
period commencing on the date hereof and ending 180 days after the date of the
final prospectus relating to the Public Offering (the "Prospectus"), (1) offer,
pledge, sell, contract to sell, sell any option or contract to purchase,
purchase any option or contract to sell, grant any option, right or warrant to
purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any
shares of Common Stock or any securities convertible into or exercisable or
exchangeable for Common Stock, or (2) enter into any swap or other arrangement
that transfers to another, in whole or in part, any of the economic consequences
of ownership of the Common Stock, whether any such transaction described in
clause (1) or (2) above is to be settled by delivery of Common Stock or such
other securities, in cash or otherwise. In addition, the undersigned agrees
that, without the prior written consent of Thomas Weisel Partners (which consent
may be withheld in its sole discretion), it will not, during the period
commencing on the date hereof and ending 180 days after the date of the
Prospectus, make any demand for or exercise any right with respect to, the
registration of any shares of Common Stock or any security convertible into or
exercisable or exchangeable for Common Stock. With respect to the Public
Offering, the undersigned waives any registration rights relating to
registration under the Securities Act of any Common Stock owned either of record
or beneficially by the undersigned, including any rights to receive notice of
the Public Offering.



     The foregoing restrictions are expressly agreed to preclude the undersigned
from engaging in any hedging or other transaction that is designed to or
reasonably expected to lead to or result in a sale or disposition of the Common
Stock even if such Common Stock would be disposed of by someone other than the
undersigned. Such prohibited hedging or other transactions would include without
limitation any short sale or any purchase, sale or grant of any right (including
without limitation any put option or put equivalent position or call option or
call equivalent position) with respect to any of the Common Stock or with
respect to any security that includes, relates to, or derives any significant
part of its value from such Common Stock.

     Notwithstanding the foregoing, the undersigned may transfer shares of
Common Stock (i) as a bona fide gift or gifts, provided that the donee or donees
thereof agree to be bound by the restrictions set forth herein, (ii) to any
trust for the direct or indirect benefit of the undersigned or the immediate
family of the undersigned, provided that the trustee of the trust agrees to be
bound by the restrictions set forth herein, and provided further that any such
transfer shall not involve a disposition for value, (iii) to the Underwriters
pursuant to the Underwriting Agreement, or (iv) in transactions relating to
shares of Common Stock acquired by the undersigned in open market transactions
after the completion of the Public Offering. For purposes of this Agreement,
"immediate family" shall mean any relationship by blood, marriage or adoption,
not more remote than first cousin. In addition, notwithstanding the foregoing,
if the undersigned is a corporation, the corporation may transfer the capital
stock of the Company to any wholly-owned subsidiary of such corporation;
provided, however, that in any such case, it shall be a condition to the
transfer that the transferee execute an agreement stating that the transferee is
receiving and holding such capital stock subject to the provisions of this
Agreement and there shall be no further transfer of such capital stock except in
accordance with this Agreement, and provided further that any such transfer
shall not involve a disposition for value.

     The undersigned understands that whether or not the Public Offering
actually occurs depends on a number of factors, including stock market
conditions. The Public Offering will only be made pursuant to an Underwriting
Agreement, the terms of which are subject to negotiation among the Company and
the Underwriters.

     The undersigned agrees and consents to the entry of stop transfer
instructions with the Company's transfer agent and registrar against the
transfer of shares of Common Stock or securities convertible into or
exchangeable or exercisable for Common Stock held by the undersigned except in
compliance with the foregoing restrictions.

     This Agreement is irrevocable and will be binding on the undersigned and
the respective successors, heirs, personal representatives, and assigns of the
undersigned.

                                   Very truly yours,


                                   _____________________________________________
                                   (Signature)


                                   _____________________________________________
                                  (Print Name)


                                   _____________________________________________
                                   (Address)

                                                                             -2-

EX-10.1

                                                                    Exhibit 10.1
                                  CONFIDENTIAL

                           IMPAC MEDICAL SYSTEMS, INC.

                         SOFTWARE DISTRIBUTION AGREEMENT

     This Software Distribution Agreement (this Agreement) is entered into
between IMPAC Medical Systems, Inc., a California corporation (IMPAC), and
Siemens Medical Systems, Inc., a Delaware corporation (Siemens).

                                   Background

         IMPAC owns or has rights to various software products relating to
healthcare information and data management. Siemens is in the business of
distributing software products to its customers. The parties desire that Siemens
sublicense and distribute certain of IMPAC's products to Siemens' customers in
accordance with the provisions of this Agreement.

         Therefore the parties agree as follows:

1.  Definitions.

    1.1  "Affiliate" means any business entity directly or indirectly
         controlling, under common control with, or controlled by either party
         to this Agreement or any third party identified herein. For purposes of
         the foregoing, "control" shall include the right, directly or
         indirectly, to direct the management of an entity by ownership of more
         than fifty percent (50%) of the voting stock (or its equivalent)
         entitled to determine or remove the board of directors (or their
         equivalent).

    1.2  "Alpha," "Alpha Product," "Alpha Release" means a Product in that stage
         of the product lifecycle that applies to new products undergoing
         software prototype evaluation by one or more IMPAC customers or
         End-Users for a finite period of time prior to formal release for the
         purpose of providing user validation of requirements. Alpha Releases
         shall only be used non-clinically, ***.

    1.3. "Beta," "Beta Product," "Beta Release" means a Product in that stage of
         the product lifecycle that applies to new products or *** existing
         products, not necessarily feature-complete, that are placed in limited
         distribution to select sites for a finite period of time for the
         purpose of testing, feedback, and revision, with the expectation that
         feedback from the End-Users shall be used to ensure the product meets
         specified requirements and functions as intended. A Beta Release may be
         used ***. Furthermore, all Beta Releases must be provided to End-Users
         subject to End-User Agreements.***.

    1.4  "Confidential Information" means all confidential or proprietary
         (written, recorded or oral) information or data (a) marked or
         identified by the disclosing party as being confidential or proprietary
         or (b) that the receiving party should reasonably understand to be
         confidential or proprietary. By way of example and not limitation,
         Confidential Information may include research, developmental,
         engineering, manufacturing, technical, marketing, sales, financial,
         operating, performance, cost,

    ***  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.



                                  CONFIDENTIAL

              business and process information or data, know-how, and computer
              programming and other software and software techniques.

   1.5.       "Discloser" means a party disclosing Confidential Information to
              the other party under this Agreement and pursuant to and subject
              to the provisions of Section 14 of this Agreement.

   1.6.       "Documentation" means End-User manuals, product descriptions,
              product specification sheets ***, and other written materials that
              relate to one or more of the Products. Documentation shall include
              these written materials with respect to Maintenance Modifications,
              upgrades, updates, and Enhancements if, when, and to the extent
              delivered to Siemens by IMPAC under, or in connection with, this
              Agreement.

   1.7.       "Effective Date" means the date on which the last party to sign
              this Agreement does so.

   1.8.       "End-User" means a person or entity who licenses one or more of
              the Products for internal use only, and not for further
              redistribution.

   1.9        "End-User Agreement" means an agreement substantially in the form
              of, and containing terms no less protective than, the agreement
              attached to this Agreement as Exhibit B, under which End Users are
              granted a license to use the Products.

   1.10       "Enhancement" means an individually controlled or registered
              modification, addition, or substitution by IMPAC generally made
              available to IMPAC's customers from time to time, other than a
              Maintenance Modification, that accomplishes one or more
              performance, structural, or functional improvements to Products.

   1.11       "IMPAC Marks" means without limitation all trademarks, service
              marks, trade names, and trade dress owned or licensed by IMPAC.

   1.12       "Inspection Period" means that number of days or period of time
              designated in subsection 5.3 of this Agreement during which
              Siemens may inspect and test the Products, and determine and
              effectively communicate, pursuant to the provisions of subsection
              5.3, whether Siemens accepts or rejects any Product unit.

   1.13       "Intellectual Property Rights" means all worldwide intellectual
              property rights, including, but not limited to, patents,
              copyrights, authors' rights, trademarks, trade names, know-how,
              and trade secrets, irrespective of whether these rights arise
              under U.S., foreign, or international intellectual property,
              unfair competition, or trade secret laws.

   1.14       "Interface Products" means those Siemens software and hardware
              products that enable Siemens' radiotherapy treatment machines and
              simulators to interface with other products.

*** 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.

                                        2



                                  CONFIDENTIAL

   1.15       "Maintenance Modification" means a modification, update, or
              revision by IMPAC generally made available in IMPAC's sole
              discretion to IMPAC's customers from time to time that corrects
              errors or responds to routine maintenance or support requirements
              of Products. Maintenance Modifications may include without
              limitation modifications, updates, or revisions made to support
              industry-standard changes in supported operating systems, and to
              comply with regulatory requirements.

   1.16       "Maintenance Period" means that number of years or other time
              period *** during which IMPAC shall be obligated, pursuant to the
              provisions of subsection 9.1 to provide continuing support of the
              Products.

   1.17       "Object Code" means executable computer programming code in
              machine-readable form generated by compilation, assembly, and
              linking of Source Code, together with machine-readable program and
              data files, and contained in a medium that permits it to be loaded
              and operated on a computer system. Object Code shall not be
              construed to encompass customer or End-User generated data.

   1.18       "Pilot," "Pilot Product," "Pilot Release" means Products in that
              period of the product lifecycle that applies to products with new
              feature additions or enhancements that are placed in controlled or
              conditional customer distribution for a finite period of time ***.

   1.19       "Production," "Production Product," "Production Release" means a
              product in that stage of the product lifecycle that applies to
              products released for distribution to End-Users pursuant to the
              provisions of the End-User Agreement, and that does not constitute
              an Alpha, Beta, or Pilot Product.

   1.20       "Products" means the software products proprietary to IMPAC, its
              licensors, or both, that are permitted to be distributed by
              Siemens under this Agreement, as set forth on Exhibit A, as
              modified and added to from time to time upon mutual agreement of
              the parties. Products shall also include all updates, upgrades,
              Enhancements, and Maintenance Modifications to the Products
              completed pursuant to this Agreement, and any accompanying related
              Documentation.

   1.21       "Purchase Order" means an order that shall include customer name
              and location, ***, sales order number, software part numbers,
              software descriptions, quantity, unit price, total order amount,
              and the products and equipment, if any, with which the Products
              will be distributed.

   1.22       "Radiation Oncology Distributor" means a business entity that
              derives *** from the sale of radiation therapy specific products
              and services to end-users.

   1.23       "Recipient" means a party receiving Confidential Information from
              the other party under this Agreement and pursuant to and subject
              to the provisions of Section 14 of this Agreement.

*** 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.

                                        3



                                  CONFIDENTIAL

   1.24       "RMA" means returned material authorization used with and governed
              by the inspection and acceptance provisions of subsection 5.3.

   1.25       "Siemens Marks" means all trademarks, service marks, trade names,
              and trade dress owned or licensed by Siemens.

   1.26       "Source Code" means computer programming code in human-readable
              programming language together with all comments and procedural
              code such as job control language statements and all related
              development documents such as flow charts, schematics, statements
              of principles of operations, architectural standards and other
              specifications that are used to create the relevant software.

   1.27       "Subdistributor" means those third parties that act as
              subdistributors of the Products through Siemens pursuant to the
              provisions of subsection 2.4.

   1.28       "Support Year" means that year-long time period measured from
              October 1 to September 30.

   1.29       "Termination Date" means the effective date of termination or
              expiration of this Agreement.

   1.30       "Territory" means that territory within which Siemens, its
              Affiliates, and its Subdistributors are permitted to distribute
              the Products. For purposes of this Agreement, the Territory shall
              be worldwide.

   1.31       "VMI/Siemens Software" means ***.

2. Distribution Generally.

   2.1        Non-Exclusive Appointment. Subject to the licenses and
              restrictions set forth in this Agreement, IMPAC appoints Siemens
              as a non-exclusive distributor of the Products to End-Users within
              the Territory.

   2.2        Marketing and Promotional Efforts. Siemens shall use commercially
              reasonable efforts to market, promote, and distribute the
              Products. These efforts may include without limitation the use of
              mailings, telemarketing programs, advertising, seminars, and other
              customary marketing techniques.

   2.3        Affiliates. Siemens shall be entitled to distribute the Products
              through Siemens' Affiliates; provided, however, that each
              Affiliate acknowledges, adheres to, and does not perform any act
              inconsistent with, the terms and conditions of this Agreement, and
              provided further that Siemens shall remain responsible for the
              full compliance by each Affiliate with the provisions of this
              Agreement. Siemens shall ensure that all Affiliates cease
              distribution of Products upon termination of Siemens' rights to do
              so hereunder. ***

*** 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.

                                        4



                                  CONFIDENTIAL

   2.4        Subdistributors. Siemens shall be entitled to distribute the
              Products through those Subdistributors engaged to so distribute
              the Products as of the Effective Date of this Agreement; provided,
              however, that Siemens shall ensure that each Subdistributor
              acknowledges, adheres to, and does not perform any act
              inconsistent with, the terms and conditions of this Agreement, and
              provided further that Siemens shall remain responsible for the
              full compliance by each Subdistributor with the provisions of this
              Agreement. Siemens shall ensure that all Subdistributors cease
              distribution of Products upon termination of Siemens' rights to do
              so hereunder. ***

   2.5        Labeling. In the event that Siemens markets or distributes any
              Product under any Siemens Mark, name or logo, other than those
              authorized for use with the Product as set forth in Exhibit A,
              Siemens shall not use or display any IMPAC Mark in connection with
              the Product without IMPAC's prior written approval.

   2.6        Feedback by Siemens. Siemens shall use commercially reasonable
              efforts to provide IMPAC with prompt written notification of
              any comments or complaints about the Products that are made by
              End Users, and ***.

3. Pricing and Payment.

   3.1        Pricing. Beginning on the Effective Date and continuing through
              September 30, 2001, the pricing of the Products shall remain at
              those prices delineated pursuant to that certain Software
              Development and OEM License Agreement between the parties, dated
              as of October 1, 1992, as subsequently amended. Thereafter, IMPAC
              shall supply Products and training to Siemens at prices in
              accordance with the price list set forth in Exhibit A. Unless
              otherwise set forth therein, the prices in Exhibit A shall remain
              in effect for a period beginning October 1, 2001 and extending for
              ***. Thereafter IMPAC may modify the prices in its discretion no
              more frequently than ***.

   3.2        ***.

              3.2.1   ***.

              3.2.2.  Distribution Rights to New Radiation Oncology Products.
                      Subject to the terms of this Agreement, ***, Siemens shall
                      be entitled to distribute all those new products developed
                      by IMPAC the primary functionality of which specifically
                      addresses the planning, verification, or delivery of
                      radiation treatments, ***.

   3.3        Payment. Siemens shall pay for Products supplied hereunder within
              *** following Siemens' receipt of the Products and IMPAC's invoice
              thereof in accordance with this Agreement. Any payments due from
              Siemens hereunder which are not paid by Siemens within *** after
              becoming due and payable shall incur a late charge ***.

*** 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.

                                       5



                                  CONFIDENTIAL

4. Forecasts, Orders, and Delivery of Products

   4.1        Forecasts. During the term of this Agreement, Siemens shall
              provide IMPAC with a good faith rolling twelve (12) month
              forecast, updated quarterly, for units of the Products requested
              to be provided by IMPAC to Siemens hereunder during each month in
              this twelve (12) month period.

   4.2        Orders. All Product orders placed by Siemens shall be accompanied
              by ***. In the event of any conflict or inconsistency between the
              terms and conditions of any Purchase Order and this Agreement, the
              terms and conditions of this Agreement shall prevail.

              4.2.1   Order Processing. Upon receipt by IMPAC of *** sent by
                      Siemens, IMPAC shall verify the order, *** and return to
                      Siemens *** the following ***. IMPAC shall exercise
                      commercially reasonable efforts to complete the order
                      processing within *** of receipt of an accurate and
                      complete *** from Siemens. Notwithstanding the foregoing
                      sentence, the parties agree to work together to limit the
                      time for completion of order processing ***.

              4.2.2   Order Cancellation or Termination. In the event any
                      customer of Siemens cancels or terminates its order for or
                      agreement to obtain Products from Siemens ***. The
                      cancellation or termination procedures outlined in this
                      subsection 4.2.2 shall not apply to any third-party
                      products supplied by IMPAC to Siemens.

              4.2.3.  Order ***. In the event any customer of Siemens cancels or
                      terminates its order for or agreement to obtain Products
                      from Siemens, ***. If, ***, then on a case-by-case basis,
                      IMPAC shall review Siemens' request for an exception to
                      the *** process as set out in this subsection 4.2.3, and
                      if, in IMPAC's sole discretion, the exception is
                      warranted, then IMPAC may allow Siemens to ***.

   4.3        Product *** Delivery.

              4.3.1   *** Products. To facilitate Siemens' distribution of the
                      Products to its End-Users, IMPAC shall *** or by other
                      means specified from time to time by IMPAC in its sole
                      discretion.

              4.3.2   End-User ***. Subject to the terms of this Agreement, upon
                      receipt by IMPAC of *** required under section 4.2.1, and
                      otherwise as may be specified from time to time in IMPAC's
                      sole discretion, IMPAC shall transfer to Siemens ***.

5. Packing, Shipping and Returns.  For those products ***, the following
   provisions shall apply.

*** 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.

                                       6




                                  CONFIDENTIAL

    5.1  Packing and Documentation. Unless otherwise specified in the applicable
         Purchase Order, IMPAC shall use commercially reasonable efforts to pack
         all Products to be delivered hereunder: (a) to ensure safe arrival at
         their ultimate destination, (b) to secure the lowest transportation
         costs, and (c) to comply with requirements of the common carrier
         selected. Siemens' order numbers and symbols must be plainly marked on
         all invoices, packages, bills of lading and shipping orders. Shipping
         memos or packing lists must accompany all Products to be delivered
         hereunder, and bills of lading or shipping receipts must accompany each
         invoice. Siemens' count shall be final and conclusive on shipments not
         accompanied by shipping memos or packing lists. Shipments shall be
         routed in accordance with Siemens' instructions.

    5.2  Shipping and Risk of Loss. IMPAC shall ship Products ordered by Siemens
         within ***, unless a delayed shipment or delivery date is specified in
         the Purchase Order, in which case IMPAC shall ship Products for
         delivery as specified in the Purchase Order. Shipping shall be FOB
         IMPAC's facility (or, for shipments to be made outside of the United
         States, EXW IMPAC's facility per Incoterms 2000). Unless otherwise
         specified in the applicable Purchase Order, all freight charges shall
         be added to the invoices. Risk of loss of or damage to Products shall
         pass to Siemens at the time the Products leave the loading dock of
         IMPAC's facility.

    5.3  Inspection and Acceptance. Siemens' Inspection Period shall be ***
         after delivery of Product shipped by IMPAC to Siemens. If Siemens
         determines that any Product fails to meet the applicable Documentation
         in any material way, Siemens may reject the Product by notifying IMPAC
         in writing of the rejection and requesting a Returned Material
         Authorization ("RMA") number; provided, that the written notification
         and request for an RMA number must be received by IMPAC during the
         Inspection Period. IMPAC shall provide the RMA number within *** after
         its receipt of this request by Siemens. Within *** after receipt of the
         RMA number, Siemens shall return the defective units to IMPAC, insured
         and with transportation prepaid, in the same condition as at the time
         of delivery to Siemens, in the same or equivalent shipping container,
         and with a written description of the defect. If IMPAC confirms the
         defect, Siemens shall ***.

6. IMPAC Licenses, Restrictions and Ownership.

    6.1  End User Licenses. With respect to each copy of the Object Code for
         each Product provided to Siemens by IMPAC hereunder, and subject to the
         provisions of this Agreement, IMPAC hereby grants to Siemens a ***,
         non-exclusive, *** license to distribute the Object Code copy to an
         End-User within the Territory solely for the End-User's own internal
         use, and to permit the End-User to make one (1) back-up or archival
         copy of the Object Code. All sublicenses shall be made subject to the
         End-User Agreement. Upon execution of any End-User Agreement, Siemens
         shall *** in accordance with the *** procedures established, from time
         to time, by IMPAC. These *** procedures shall *** require Siemens to
         provide IMPAC with the applicable Purchase Order number, the name and
         address of the End-User, the Products and the corresponding number of
         seats licensed, if applicable. In the event

*** 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.

                                        7





                                  CONFIDENTIAL

         Siemens upgrades the operating system of any End-User for whom one or
         more Products were previously ***, which End-User desires to continue
         the sublicense under the same terms and conditions, Siemens shall ***.
         Siemens may sublicense its right hereunder to its Affiliates and
         Subdistributors, subject to all of the provisions and restrictions of
         this Agreement; provided, however, that Siemens shall remain
         responsible for the full compliance of each Affiliate and
         Subdistributor with the provisions of this Agreement.

    6.2  Limited *** License. Subject to the provisions of this Agreement, IMPAC
         hereby grants to Siemens a ***, worldwide, ***, and non-exclusive
         license, which, may be sublicensed to Affiliates and Subdistributors of
         Siemens only in accordance with the provisions of Section 2 of this
         Agreement, ***.

    6.3  Restrictions. Neither Siemens, nor any of its Affiliates or
         Subdistributors shall remove or obscure any proprietary notice in
         connection with any of the Products. Siemens and its Affiliates and
         Subdistributors shall reproduce and include those proprietary notices
         on any copies of the Products permitted under this Agreement. Except as
         expressly set forth in this Agreement, neither Siemens, nor any of its
         Affiliates or Subdistributors shall use, reproduce, distribute,
         sublicense, sell, encumber, modify or create derivative works of the
         Products in whole or in part. Neither Siemens, nor any of its
         Affiliates or Subdistributors shall copy, translate, disassemble,
         decompile, or otherwise attempt to discover the Source Code for the
         Products. Neither Siemens, nor any of its Affiliates or Subdistributors
         shall authorize any third party to take any action that Siemens is
         prohibited from taking under this subsection 6.3.

    6.4  Product Ownership. Siemens acknowledges and agrees that, except for the
         licenses expressly granted under this Agreement, IMPAC retains all
         right, title and interest in and to the Products, including without
         limitation all Intellectual Property Rights therein and the tangible
         medium in which the Products are embodied.

7. *** Further Agreements from Siemens.

    7.1  ***.

    7.2  ***.

8. Training.

    8.1  Continuing Training. IMPAC shall provide to Siemens instructors and
         materials for product and service training for all releases provided
         pursuant to this Agreement that IMPAC in its sole discretion designates
         as significant functional improvements. Releases subject to this
         training requirement generally shall include ***. The parties agree to
         exercise reasonable efforts to complete this training within ***. This
         training shall consist of *** of applications training and *** of sales
         and service

*** 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.

                                        8




                                  CONFIDENTIAL

         training ***. IMPAC shall provide this training at locations ***, at
         times mutually agreed upon by IMPAC and Siemens ***.

    8.2  Other Training. In the event Siemens desires IMPAC to provide any
         training in addition to that provided in Section 8.1, Siemens shall
         request this training in writing and IMPAC shall provide the training
         at the rates set forth in Exhibit A, at locations to be designated by
         Siemens and at times mutually agreed upon by IMPAC and Siemens (in
         their reasonable discretion). Travel, room and board expenses shall be
         borne and paid as provided in Section 8.1.

9. Support and Maintenance.

    9.1  Support Services. During the term of this Agreement, IMPAC shall supply
         support to Siemens for the Products as set forth in subsections 9.1.1
         and 9.1.2 below. In addition, for each individual Product for which
         Siemens provides its End-Users with support, IMPAC shall supply support
         for ***.

         9.1.1 Enhancements and Maintenance Modifications. IMPAC shall provide
               to Siemens *** Enhancements and Maintenance Modifications to the
               Products *** consistent with the testing, evaluation, and review
               provisions of section 11 of this Agreement.

         9.1.2 Telephone Support. IMPAC shall provide to Siemens reasonable
               levels of telephone support with respect to the Products between
               the hours of *** and *** Pacific Time, *** through ***, IMPAC
               holidays excepted.

         9.1.3 Investigative or Corrective Action. IMPAC shall initiate
               commercially reasonable investigative or corrective action to (1)
               rectify a *** discrepancy or *** discrepancy within *** of
               receipt by IMPAC of Siemens' written notice of the discrepancy;
               (2) rectify a *** discrepancy within *** of receipt by IMPAC of
               Siemens' written notice to IMPAC of the discrepancy; or (3)
               rectify a *** discrepancy within *** of receipt by IMPAC of
               Siemens' written notice of such discrepancy. Any written notices
               provided by Siemens under this section shall include a detailed
               description of such discrepancy, a description of the operating
               environment, and if known, the actions required to reproduce the
               discrepancy. The parties agree to work together in good faith to
               establish any necessary additional processes or procedures to
               further the intent of this section. The parties further agree to
               commence a review of current processes and procedures within
               ninety (90) days of the Effective Date of this Agreement.

    9.2  Support Fees. Within *** following the beginning of a Support Year as
         full consideration for the support provided during that Support Year,
         Siemens shall pay IMPAC the following amounts: ***.




*** 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.

                                        9



                                  CONFIDENTIAL

    9.3  *** Support. During the applicable Maintenance Period for each Product,
         IMPAC shall:


         9.3.1 supply patient safety related error correction releases for each
              Product to Siemens at no additional cost;

         9.3.2 offer to license to Siemens for sublicense to End-Users any
              Maintenance Modifications for each Product that IMPAC offers to
              IMPAC's End-Users at a price to be determined solely by IMPAC.
              ***. All sublicenses to Siemens's End-Users shall be subject to
              terms not less restrictive than those set forth in Exhibit B of
              the Agreement; and

         9.3.3 provide ongoing telephone support to Siemens's application and
              service personnel from *** to *** (PST), *** through ***, IMPAC
              holidays excepted.

    9.4. Failure to Pay. Except for IMPAC's obligations under subsection 9.3.1,
         IMPAC shall not be obligated to perform as set forth in subsections
         9.1, 9.2 or 9.3 above ***.

10.  Records and Audits. During the term of this Agreement and for a period of
     ***, Siemens shall maintain true and accurate books and records of all
     sublicenses made by it to End Users in sufficient detail to calculate the
     amounts due under this Agreement, for the *** immediately preceding the
     date of the audit. During the term of this Agreement and for a period of
     ***, at IMPAC'S request and sole expense, at mutually agreeable times, but
     not more frequently than ***, an accounting firm *** shall be provided
     reasonable access, during Siemens' normal business hours, to the books,
     records and employees of Siemens for purposes of auditing records of
     Products ordered from and shipped by Siemens and verification of Siemens'
     compliance with other obligations under this Agreement. The accounting firm
     conducting the audit shall be required to execute a written confidentiality
     agreement for the benefit of Siemens, substantially in the form attached to
     this Agreement as Exhibit D, prior to commencing the audit. The cost of any
     such audit shall be borne by IMPAC unless the audit reveals an aggregate
     underpayment by Siemens for the period being audited of greater than ***,
     in which case Siemens shall promptly reimburse IMPAC for the cost of the
     audit.

11.  Siemens Product Testing, Evaluation, and Review.

    11.1 Siemens shall, at IMPAC's discretion and at no charge, *** provide
         testing and evaluation information as requested by IMPAC with respect
         to any new Products and Enhancements developed during the term of this
         Agreement. Siemens shall treat all new Products, Enhancements, and
         descriptions and evaluations thereof as Confidential Information of
         IMPAC. In addition, IMPAC shall use commercially reasonable efforts to
         consider all proposals provided by Siemens in connection with the new
         Products and proposed Modifications and Enhancements to the Products,
         and shall provide reports to Siemens from time to time with respect to
         Siemens proposals. These proposals and reports shall constitute
         Confidential Information of IMPAC.

*** 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.

                                       10



                                  CONFIDENTIAL

    11.2 IMPAC shall grant Siemens access to ***. Use, testing, evaluation, and
         review by Siemens of those releases shall be in accordance with (a) the
         definitions of those releases as set forth in section 1 of this
         Agreement, (b) ***, and (c) *** other restrictions or guidelines
         established by IMPAC in its sole discretion. With each *** Release to
         which Siemens is granted access, IMPAC shall supply that Documentation
         available for that particular release of that product. If Siemens
         requests training for a release, it shall be conducted in accordance
         with the training provisions of this Agreement.

12. Source Code Escrow.

    12.1 During the term of this Agreement, IMPAC shall maintain a copy of the
         Source Code for the Products set forth in Appendix A and all
         documentation thereto (collectively, the "Escrowed Materials") with
         ***, pursuant to the Source Code Escrow Agreement between IMPAC and
         Siemens entered into on or about December 5, 2000, as it may be
         modified to reflect the terms set forth in this Agreement. In the event
         of a conflict between the Source Code Escrow Agreement and this section
         12, the Source Code Escrow Agreement shall govern. The Escrowed
         Materials shall be deemed Confidential Information and shall be subject
         to the confidentiality restrictions set forth in Section 14. IMPAC
         shall update the Escrowed Materials *** during the term of this
         Agreement. The escrow agreement shall continue until the expiration of
         the ***. Siemens shall bear all escrow fees incurred pursuant to this
         section. The parties acknowledge that the escrow agreement is an
         agreement supplementary to this Agreement, as provided under Section
         365(n) of the Bankruptcy Code.

    12.2 Escrowed Materials shall be released to Siemens upon the occurrence of
         the following events (each, a "Release Condition"):

         12.2.1 A proceeding relating to the liquidation or insolvency of IMPAC
                is commenced and is not dismissed within *** of commencement;

         12.2.2 During the term of the Agreement, IMPAC materially fails to
                provide support in accordance with subsection 9.1.2 within ***
                of receipt by IMPAC of Siemens' written notice of such a failure
                (which notice shall specify in detail the manner in which IMPAC
                is failing to provide this support);

         12.2.3 During the term of the Agreement, IMPAC materially fails to
                provide support in accordance with subsection 9.1.3; or

         12.2.4 During the Maintenance Period, IMPAC materially fails to perform
                the obligations set forth *** in which IMPAC is failing to
                perform).

    12.3 Upon the release of the Escrowed Materials pursuant to a Release
         Condition set forth in subsection 12.2 above, Siemens shall have a
         non-exclusive, non-transferable right, subject to the restrictions set
         forth in this Agreement to use, modify, and make working copies of the
         Escrowed Materials for the sole purpose of supporting and

*** 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.

                                       11



                                  CONFIDENTIAL

         maintaining *** the Products (the "Escrow Support License"); provided,
         however, that the Escrow Support License for each Product shall
         automatically terminate at the end of the applicable Maintenance Period
         for each such Product. Upon the release of the Escrowed Materials
         pursuant to subsection 12.2.1, Siemens shall have a non-exclusive,
         non-transferable right, subject to the restrictions set forth in this
         Agreement to use, reproduce, sublicense, and distribute the Products to
         End-Users in object code form only (the "Escrow Distribution License");
         provided, however, that (1) all such End-User sublicenses shall be
         subject to terms not less restrictive than those set forth in Exhibit B
         of this Agreement; (2) Siemens shall pay a royalty to IMPAC on each
         unit of Product reproduced and distributed to End-Users, which royalty
         shall be equivalent to IMPAC's then-current transfer price for each
         such Product as set forth in the then-current Exhibit A; and (3) the
         Escrow Distribution License shall terminate automatically upon the
         termination or expiration of the then-current term of the Agreement. In
         the event that the source code is released to Siemens pursuant to
         subsections 12.2.2, 12.2.3, or 12.2.4, and ***, Siemens shall have an
         Escrow Distribution License, subject to the terms set forth above.
         Except for sublicensing the right to use the Products to End-Users,
         Siemens shall have no right to sublicense any of the rights granted
         pursuant to this Section 12. Upon the cessation or cure of either of
         the Release Conditions specified in subsection 12.2 above, both the
         Escrow Support License and Escrow Distribution License (if any) shall
         terminate, and Siemens promptly return all copies of the Escrowed
         Materials, or any portion thereof, to ***.

13.Marks.

    13.1 Siemens Marks. Siemens shall own and have sole control of the use of
         all Siemens Marks. IMPAC acknowledges all right, title and interest of
         Siemens in and to the Siemens Marks. IMPAC has no license to or right
         in the Siemens Marks and shall not use them in its marketing or sales
         literature or in any other way, without the prior written consent of
         Siemens. Notwithstanding the foregoing, IMPAC may apply the Siemens
         Marks to Products if requested to do so under any Purchase Order
         accepted by IMPAC, which request shall constitute the prior written
         consent of Siemens. IMPAC may not represent in its marketing and sales
         literature and oral presentations that the Products are compatible with
         Siemens's equipment and that Siemens is a distributor of Products
         without the prior written consent of Siemens, which consent shall not
         be unreasonably withheld.

    13.2 IMPAC Marks. IMPAC shall own and have sole control of the use of all
         IMPAC Marks. Siemens acknowledges all right, title and interest of
         IMPAC in and to the IMPAC Marks. Siemens has no license to or right in
         the IMPAC Marks and shall not use them in its marketing or sales
         literature or in any other way, without the prior written consent of
         IMPAC, which consent shall not be unreasonably withheld.

*** 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.

                                       12



                                  CONFIDENTIAL

14. Confidentiality.

    14.1 Treatment of Confidential Information. Each Recipient receiving
         Confidential Information from a Discloser pursuant to this Agreement
         shall (and shall cause its Affiliates to): (a) hold confidential and
         not disclose to persons or entities other than Recipient's Affiliates
         having a reasonable need to know the Confidential Information in
         connection with the permitted purposes hereunder, without the prior
         written consent of the Discloser, all Confidential Information provided
         by the Discloser or the Discloser's Affiliates; (b) use the
         Confidential Information only for the purposes for which it is
         delivered to the Recipient, and for no other purposes whatsoever,
         except with the prior written consent of the Discloser; and (c) return
         the Confidential Information (with all copies thereof and all portions
         of documents prepared by or for the Receiving Party or Recipient's
         Affiliates which contain Confidential Information) to the Discloser
         (or, at the option of the Recipient, destroy all Confidential
         Information, including all copies thereof and all portions of the
         documents containing Confidential Information, and provide the
         Discloser with a certificate of an officer of the Recipient stating
         that the destruction has occurred) within *** of receipt by the
         Recipient of a written request therefor from the Discloser except to
         the extent the Recipient shall have a continuing right to retain the
         Confidential Information pursuant to this Agreement or other written
         agreement entered into between parties.

    14.2 Exceptions. The obligations imposed by subsection 14.1 hereof shall not
         apply, or shall cease to apply, to any Confidential Information if or
         when, and to the extent that, the Confidential Information: (a) was
         known to the Recipient or the Recipient's Affiliates prior to the
         receipt of the Confidential Information from the Discloser or
         Discloser's Affiliates; (b) was, or becomes through no breach of the
         Recipient's (or any of its Affiliates') obligations hereunder, known to
         the public; (c) becomes known to the Recipient or Recipient's
         Affiliates from sources other than the Discloser or Discloser's
         Affiliates under circumstances not involving any breach of any
         confidentiality obligation between the source and the Discloser or
         Discloser's Affiliates; (d) is independently developed by the Recipient
         or the Recipient's Affiliates, without any use of or reference to the
         Discloser's Confidential Information; or (e) is required to be
         disclosed by law or applicable legal process, provided that the
         Recipient or the Recipient's Affiliates making the disclosure shall (i)
         give the Discloser as much prior notice thereof as is reasonably
         practicable so that the Discloser may seek such protective orders or
         other confidentiality protection as it, in its sole discretion and at
         its sole expense, may elect, and (ii) reasonably cooperate(s) with the
         Discloser in protecting the confidential or proprietary nature of the
         Confidential Information that must be so disclosed (with this duty of
         cooperation not requiring the Recipient or Recipient's Affiliates to
         initiate or participate in any litigation or incur more than de minimis
         out-of-pocket costs).

    14.3 Equitable Relief. Each Recipient acknowledges and agrees that due to
         the unique nature of the Discloser's Confidential Information, there
         can be no adequate remedy at law for any breach of the Recipient's
         confidentiality and use-restriction obligations under this Agreement,
         that any such breach may result in irreparable harm 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.

                                       13



                                  CONFIDENTIAL

         Discloser, and that therefore, upon any such breach or threat thereof,
         the Discloser shall be entitled to appropriate equitable relief,
         including injunctive relief, in addition to any remedies it may have
         available at law. Each party hereby waives any right it may have to
         assert that the other party has one or more adequate remedies available
         at law with respect to any breach of this Agreement in connection with
         Confidential Information.

15. Warranties and Disclaimers.

    15.1 Limited Product Warranties. IMPAC warrants to Siemens (and not to any
         third party) that each release of the Products, as delivered to Siemens
         by IMPAC, shall operate substantially in conformance with the
         Documentation for a period of *** from the date of first delivery to
         Siemens of the release. IMPAC further warrants that all Products
         provided by IMPAC to Siemens hereunder shall be free from defects in
         material and workmanship for a period of *** from the date of delivery
         to Siemens. Siemens' sole remedy for breach of the foregoing warranty
         with respect to material and workmanship shall be to return defective
         Products for replacement by IMPAC, or if IMPAC determines that repair
         and replacement is not commercially feasible, IMPAC shall refund the
         amounts paid by Siemens for the same in accordance with the provisions
         of subsection 4.2 of this Agreement.

    15.2 Product Rights. IMPAC warrants that it is the author of the Products
         and owner of all right, title and interest in and to the Products,
         except with respect to those products licensed from Siemens or third
         parties. IMPAC further warrants that it has and shall have at all times
         all rights with respect to the Products necessary to grant the
         licenses, proprietary interests and other rights granted hereunder and
         to meet all obligations hereunder. During the term of this Agreement,
         Siemens shall have uninterrupted and peaceful enjoyment of its rights
         hereunder so long as Siemens performs its obligations hereunder. To the
         extent IMPAC has obtained licenses of any third party software, IMPAC
         agrees to promptly advise Siemens of any conditions, events, or changes
         that may affect or pertain to the continuation of this enjoyment of its
         rights under this Agreement. Notwithstanding the foregoing, the only
         remedies available to Siemens, and the sole liability of IMPAC, for any
         breach of this Section 15.2 relating to the violation or infringement
         of any Intellectual Property Right shall be as provided in Section 17
         below.

    15.3 Infringement. IMPAC warrants, any information provided to Siemens
         regarding existing or past claims or disputes not withstanding, that no
         part of the Product infringes or will infringe any patent, copyright,
         trade secret, trademark or other proprietary right of any third party;
         provided, however, that the only remedies of Siemens for breach of the
         foregoing warranty shall be as provided in Section 17. Except as
         disclosed in writing to Siemens at or prior to execution of this
         Agreement, IMPAC represents that, to the best of its knowledge, no
         claim or action relating to the infringement of any patent, copyright,
         trade secret, trademark or other proprietary right has been made
         against IMPAC, or against any entity from which IMPAC has obtained
         rights, with respect to any part of the Products.

*** 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.

                                       14



                                  CONFIDENTIAL

    15.4 IMPAC Services. IMPAC warrants that (i) the personnel of IMPAC
         originally assigned to perform any specific services will be so
         assigned throughout the performance of such services, so long as such
         personnel remain employed by IMPAC and to the extent reasonably
         necessary for the timely completion thereof and (ii) all services of
         IMPAC relating to the Products shall be performed in a timely
         (commensurate with the nature and degree of the reasonable needs of
         Siemens and its customers) and professional manner by qualified
         personnel of IMPAC familiar with the Products and shall conform in all
         material respects to quality standards generally observed in the
         industry for similar services.

    15.5 Compliance. Each party warrants that (i) it shall furnish all services
         and materials hereunder in compliance with applicable law and in the
         course of rendering the same, shall not violate or in any way infringe
         upon the rights of the other party or third parties, including
         property, contractual, employment, trade secret, proprietary
         information and nondisclosure rights, or any trademark, copyright or
         patent rights and (ii) all employees, servants and agents of each
         party, whenever on the other party's premises, shall obey all
         reasonable instructions issued by the other party, including work
         schedule and security procedures. Notwithstanding the foregoing, the
         only remedies available to Siemens, and the sole liability of IMPAC,
         for any breach of this Section 15.5 relating to the violation or
         infringement of any Intellectual Property Right shall be as provided in
         Section 17 below.

    15.6 Disclaimer. EXCEPT AS EXPRESSLY SET FORTH IN SECTION 15 ABOVE AND TO
         THE EXTENT PERMITTED BY APPLICABLE LAW, IMPAC DISCLAIMS ALL WARRANTIES,
         EXPRESS, IMPLIED AND STATUTORY, WITH RESPECT TO ANY PRODUCTS,
         INFORMATION, MATERIALS OR SERVICES PROVIDED BY IMPAC HEREUNDER,
         INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY, FITNESS FOR
         A PARTICULAR PURPOSE, ACCURACY, COMPLETENESS, ERROR-FREE SERVICE,
         UNINTERRUPTED SERVICE, NON-INFRINGEMENT, TITLE AND NON-INTERFERENCE.

16. Quality Assurance and Control.

    16.1 Inspection and Testing. Products supplied to Siemens under this
         Agreement shall be inspected by IMPAC (using representative sampling
         where appropriate) and, with respect to each new release, tested in
         accordance with the U.S. FDA and the MDD Quality System Requirements.
         IMPAC shall keep a record of the test results for a period of *** after
         delivery of each Product and provide Siemens with copies of these
         records on request. IMPAC shall supply to Siemens only Products that
         conform in all material respects to the Documentation and that have
         passed all IMPAC inspections. IMPAC shall supply *** with each Product
         supplied. IMPAC shall give Siemens' Project Manager written notice, not
         less than *** in advance of anticipated testing dates and telephone
         notice no less than *** in advance of actual testing, for Enhancements
         of the Products, and Siemens shall have the option of being present at
         its own expense for such testing.

*** 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.

                                       15



                                  CONFIDENTIAL

    16.2 Medical Device Compliance. The VMI Software, SEQUENCER, ViewStation,
         MLC Fit subsystems of the Products shall be marketed and distributed by
         IMPAC as medical devices as defined in the United States Food, Drug,
         and Cosmetic Act and the regulations thereunder (and similar laws in
         other countries) to the extent permitted by applicable law. IMPAC shall
         comply with all statutes and regulations applicable to design,
         manufacture, and distribution of the Products as medical devices,
         including those relating to the Quality System Regulations,
         establishment registration, device listing, pre-market approval or
         notification and medical device reporting. Siemens may, upon request,
         inspect and audit at IMPAC's facility the quality control procedures
         and methods employed by IMPAC in development and manufacture of the
         Products. IMPAC agrees also to obtain *** any additional approval or
         clearances necessary for the Product to be distributed ***. The parties
         shall mutually cooperate with respect to any reporting or approvals
         required by law or this subsection 16.2 in connection with the
         Products.

17. Indemnities; Intellectual Property Infringement.

    17.1 Personal Injury, Property Damage. Subject to subsection 17.3 below,
         IMPAC agrees to defend, indemnify and hold Siemens and its directors,
         employees, agents and Affiliates harmless from and against any and all
         damages, liability, costs and expenses (including without limitation
         reasonable attorneys' fees) arising under any third party action to the
         extent arising out of personal injury or death of a person or damage to
         tangible property (specifically excluding data and other intellectual
         property) caused or alleged to have been caused by defects in the
         Products or their manufacture or design (except to the extent that the
         defects are caused by modifications to the Products not performed or
         authorized by IMPAC). Subject to subsection 17.3 below, Siemens agrees
         to defend, indemnify and hold IMPAC and its directors, employees,
         agents and Affiliates harmless from and against any and all damages,
         liability costs and expenses (including without limitation reasonable
         attorneys' fees) in connection with any third party action to the
         extent arising out of personal injury or death of a person or damage to
         tangible property (specifically excluding data and other intellectual
         property) caused or alleged to have been caused by defects in the
         equipment and/or other products with which Siemens sublicenses or
         otherwise distributes the Products.

    17.2 Infringement Indemnity. Subject to subsection 17.3 below, IMPAC agrees
         to defend, indemnify and hold Siemens and its directors, employees,
         agents and Affiliates harmless from and against any and all damages,
         liability, costs and expenses (including without limitation reasonable
         attorneys' fees) arising under any third party action to the extent
         that the action alleges or proves that any Product, as provided by
         IMPAC to Siemens hereunder, infringes any United States patent,
         copyright, trademark or trade secret, except to the extent that any
         infringement arises from: (a) any modification to any Product after
         being provided to Siemens by IMPAC, or (b) the combination of any
         Product with any other product or equipment distributed by Siemens or
         its sublicensees. Subject to subsection 17.3 below, Siemens agrees to
         defend, indemnify and hold IMPAC and its directors, employees, agents
         and

*** 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.

                                       16



                                  CONFIDENTIAL

         Affiliates harmless from and against any and all damages, liability,
         costs and expenses (including without limitation reasonable attorneys'
         fees) arising under any third party action to the extent that the
         action alleges or proves that any Product infringes any United States
         patent, copyright, trademark or trade secret due to: (a) any
         modification to the Product after being provided to Siemens by IMPAC,
         or (b) the combination of the Product with any other product or
         equipment distributed by Siemens or its sublicensees.

    17.3 Conditions of Indemnification. In connection with any claims for which
         indemnification may be sought under this Section 17, the indemnified
         party shall give the indemnifying party prompt written notice of the
         claim, reasonable information and assistance (at the indemnifying
         party's request and expense) in connection with the defense and/or
         settlement of the claim and, subject to the provisions of this section,
         the sole right to control and direct the investigation, preparation,
         defense and settlement of the claim. In the event that the indemnified
         party fails to provide this notice or reasonable information or
         assistance, the indemnifying party shall not be relieved of its
         obligations under this Section 17 except to the extent that it is
         prejudiced by the failure. The indemnified party shall have the right
         to participate in the defense and/or settlement of the claim with
         counsel of its choosing at the indemnified party's expense. The
         indemnifying party shall not enter into any settlement adversely
         affecting any of the indemnified party's rights or obligations without
         the indemnified party's prior written consent, which shall not be
         unreasonably withheld.

    17.4 Infringement Options. If all or any part of a Product is, or in the
         reasonable opinion of IMPAC may become, the subject of any claim, suit
         or proceeding for infringement of any United States or foreign patent,
         trademark, copyright or trade secret, then without limiting any other
         remedy to which Siemens may be entitled under this Section 17, IMPAC
         may, and in the event of any adjudication that a Product or any part
         thereof infringes any United States or foreign patent, trademark,
         copyright or trade secret or if the licensing or use of a Product or
         any part thereof is enjoined, IMPAC shall, at its expense, do one of
         the following things: (a) procure for Siemens the right under the
         affected patent, trademark, copyright or trade secret to use or
         sublicense, as appropriate, the Product or the affected part thereof;
         (b) replace the Product or affected part thereof with other
         non-infringing software which satisfies the Documentation and other
         requirements of this Agreement; (c) suitably modify the Product or
         affected part thereof, without material loss of performance or
         functionality, to make it non-infringing; or (d) if Siemens determines
         that none of the foregoing remedies is commercially practicable, refund
         the payments paid by Siemens for the Product, ***.

    17.5 Exclusive Remedies. SECTIONS 17.2, 17.3 AND 17.4 STATE THE ENTIRE
         LIABILITY AND OBLIGATION OF THE PARTIES AND THEIR AFFILIATES AND THE
         EXCLUSIVE REMEDIES OF THE PARTIES AND THEIR AFFILIATES WITH RESPECT TO
         ANY ALLEGED INFRINGEMENT OF PATENT, TRADEMARK, COPYRIGHT, TRADE SECRET
         OR OTHER


*** 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.

                                       17



                                  CONFIDENTIAL

         INTELLECTUAL PROPERTY RIGHT BY THE PRODUCTS OR ANY PART THEREOF.

18. Limitations of Liability. EXCEPT WITH RESPECT TO THE INDEMNIFICATION
    OBLIGATIONS UNDER THIS AGREEMENT AND TO THE MAXIMUM EXTENT PERMITTED BY
    APPLICABLE LAW: (A) NEITHER PARTY SHALL BE LIABLE TO THE OTHER OR ITS
    AFFILIATES UNDER THIS AGREEMENT OR IN CONNECTION WITH ITS SUBJECT MATTER FOR
    SPECIAL, INDIRECT, PUNITIVE OR CONSEQUENTIAL DAMAGES (INCLUDING BUT NOT
    LIMITED TO LOSS OF BUSINESS GOODWILL, REVENUE OR PROFITS); AND (B) EXCEPT
    FOR SIEMENS' FEE PAYMENT OBLIGATIONS HEREUNDER, NEITHER PARTY SHALL BE
    LIABLE TO THE OTHER OR ITS AFFILIATES UNDER THIS AGREEMENT OR IN CONNECTION
    WITH ITS SUBJECT MATTER FOR ANY AMOUNTS IN EXCESS OF THE AGGREGATE AMOUNTS
    RECEIVED BY IMPAC UNDER THIS AGREEMENT. THIS SECTION CONSTITUTES AN
    ESSENTIAL TERM OF THIS AGREEMENT AND SHALL BE EFFECTIVE EVEN IN THE EVENT OF
    THE FAILURE OF ANY REMEDY HEREUNDER, EXCLUSIVE OR OTHERWISE.

19. Term and Termination.

    19.1 Term. The term of this Agreement shall be for a period of five (5)
         years commencing upon the Effective Date, unless earlier terminated in
         accordance herewith.

    19.2 Termination. In addition to any other remedies it may have, either
         party may terminate this Agreement at any time, without any liability
         arising from the termination, by providing written notice of
         termination to the other party following the occurrence of one or more
         of the following circumstances:

         19.2.1 the commencement of any proceeding by the other party for relief
                under the United States Bankruptcy Code (or similar law of any
                foreign jurisdiction), any assignment by the other party for the
                benefit of any of its creditors, or the appointment of a
                receiver for all or a substantial part of the other party's
                business or assets; or

         19.2.2 the other party's failure to pay money due in accordance with
                this Agreement, this failure remaining uncured *** after the
                other party's receipt of written notice thereof; or

         19.2.3 the breach of any agreement, obligation, covenant or
                representation of the other party under this Agreement, this
                breach remaining uncured in any material respect *** thereof
                from the first party.

    19.3 Effects of Termination. Upon expiration or termination of this
         Agreement for any reason, except as expressly provided in this
         Agreement, the license rights granted hereunder shall immediately
         terminate. Each party shall return to the other all copies


*** 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.

                                       18



                                  CONFIDENTIAL

         of any and all Confidential Information of the other party in its
         possession or shall certify to the other party that all of this
         Confidential Information has been destroyed, except that Siemens shall
         not be required to return or certify the destruction of any
         Confidential Information of IMPAC that is necessary for ongoing support
         by Siemens of the Products distributed by Siemens in accordance with
         this Agreement. Except in the event of termination of this Agreement by
         IMPAC pursuant to subsection 19.2 above, for a period of *** following
         the expiration or termination of this Agreement, IMPAC shall supply
         Products to Siemens (and Siemens shall have the right to sub-license
         End-Users as provided in subsection 6.1) to the extent necessary to
         fulfill any purchase order accepted by Siemens prior to expiration or
         termination of the Agreement, in accordance with the following
         conditions:

         19.3.1 In the first *** following the effective date of termination or
                expiration of the Agreement (the "Termination Date"), Products
                covered by accepted Purchase Orders in effect as of the
                Termination Date shall be supplied to Siemens at prices in
                effect as of the Termination Date; provided, however, that
                Siemens shall provide a written list to IMPAC of all these
                Purchase Orders no later than *** after the Termination Date,
                which list shall contain the customer name, quantities for each
                Product ordered, and estimated dates of delivery; and

         19.3.2 During the period beginning *** after the Termination Date and
                ending *** following the Termination Date, Products covered by
                accepted Purchase Orders in effect as of the Termination Date
                shall be supplied to Siemens at prices which shall not exceed
                *** in effect as of the Termination Date; provided, however,
                that Siemens shall provide a written list to IMPAC of all these
                Purchase Orders no later than *** after the Termination Date,
                which list shall contain the customer name, quantities for each
                Product ordered, and estimated dates of delivery.

    19.4 Additional Product Copies. During the post-termination period set forth
         in subsection 19.3 above, Siemens shall be entitled to make *** of any
         new releases of the Products provided by IMPAC for Siemens's internal
         archival, back-up, training and support purposes, which copies are to
         be retained at all times only at Siemens's facilities. Siemens shall
         erase or destroy all copies of previous releases superseded thereby
         other than not more than one (1) copy to be used only for archival
         purposes.

    19.5 Survival. The following provisions shall survive the termination or
         expiration of this Agreement: Sections ***.



20. Governing Law, Jurisdiction and Venue. This Agreement shall be governed by
    and construed under applicable U.S. federal law and the laws of the State of
    California, without regard to conflicts of laws principles and without
    regard to the United Nations Convention on Contracts for the International
    Sale of Goods. The parties agree that the California state and U.S. federal
    courts situated in Contra Costa County in the State of California shall have
    exclusive jurisdiction to resolve any disputes with respect to this
    Agreement, with each party

*** 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.

                                       19



                                  CONFIDENTIAL

    irrevocably consenting to the jurisdiction thereof for any actions, suits or
    proceedings arising out of or relating to this Agreement. Each party waives
    any right that it may have to assert that any of the foregoing forums is not
    convenient.

21. General.

    21.1 Independent Contractors. In performing their respective obligations
         hereunder, each party shall act at all times as an independent
         contractor. Nothing in this Agreement shall be construed or applied to
         create a relationship of principal and agent or employer and employee
         between the parties, and neither of them shall make any commitment,
         take any action or incur any expense in the name of or purporting to
         bind the other party or its Affiliates.

    21.2 Further Assurances. The parties shall, and shall cause their respective
         employees, agents and representatives to, prepare and execute and
         deliver, at the request and expense of any party hereto, any and all
         documents or instruments reasonably necessary or appropriate to create,
         evidence, or confirm the grant, discharge or release, as the case may
         be, of any right, interest or obligation required by the provisions of
         this Agreement.

    21.3 Entire Agreement and Amendment. This Agreement represents the entire
         understanding and agreement of the parties with respect to the
         particular subject matter hereof and supersedes all prior
         communications, agreements and understandings between the parties
         relating to the subject matter hereof, including without limitation
         that certain Software Development and OEM License Agreement between the
         parties, dated as of October 1, 1992, as subsequently amended. In the
         event of a conflict between this Agreement and any exhibit or purchase
         order, this Agreement shall govern. This Agreement may not be modified
         or amended except by a written instrument duly executed by both
         parties.

    21.4 Costs and Attorneys' Fees. The prevailing party in any action to
         enforce this Agreement shall be entitled to recover reasonable costs
         and expenses in connection with the enforcement, including without
         limitation reasonable attorneys' fees and expenses.

    21.5 Cumulative Remedies. Except as otherwise expressly set forth herein,
         all remedies available to either party for breach of this Agreement are
         cumulative and may be exercised concurrently or separately, and the
         exercise of any one remedy shall not be deemed an election of that
         remedy to the exclusion of any other remedy.

    21.6 Waivers. No right under this Agreement or breach hereof may be waived
         except in writing signed by the parties hereto. The failure of either
         party to require performance of any provision of this Agreement shall
         not be construed as a waiver of that party's rights to insist on
         performance of the provision or any other provision at some other time.


                                       20



                                  CONFIDENTIAL

    21.7  Assignment and Binding Effect. This Agreement may not be assigned by
          either Party without the prior written consent of the other; provided,
          however, that either party may assign this Agreement in its entirety
          to an Affiliate or successor in interest to the business of the party,
          after written notice to the other party, if the Affiliate or successor
          is able to and does fulfill the obligations of the assigning party.
          This Agreement shall be binding on, and inure to the benefit of, the
          respective successors of the parties thereto.

    21.8  Counterparts. This Agreement may be signed in duplicate originals,
          each of which shall constitute an original document.

    21.9  Notices. Any notice in connection with this Agreement shall be in
          writing and delivered by hand or after being mailed, postage prepaid,
          certified or registered mail, return receipt requested, addressed as
          set forth on the signature page below, to the attention of "Legal
          Department," or any other address as a party designates by giving
          notice to the other party in accordance with this section. Notices
          shall be effective only upon receipt.

    21.10 Force Majeure. Neither party shall be responsible for any failure to
          perform or delay in performing any of its obligations hereunder where
          and to the extent that the failure or delay results from causes
          outside the reasonable control of the party.

    21.11 Foreign Reshipment Liability. Notwithstanding anything contained in
          this Agreement, Siemens shall not export or re-export any Product or
          information pertaining thereto in violation of any United States law
          applicable to the export or re-export of the Product or information.

    21.12 Exhibits. The following Exhibits are attached hereto and made a part
          of this Agreement:


              Exhibit A: Products and Training with Pricing

              Exhibit B: Form of End-User Agreement

              Exhibit C: Affidavit of Destruction or Re-Registration and
                         Indemnity Agreement


              Exhibit D: Form of Confidentiality Agreement

                                       21



                                  CONFIDENTIAL

         The parties have caused their duly authorized representatives to
execute and deliver this Agreement as of the Effective Date.




                                                          
IMPAC Medical Systems, Inc.                                  Siemens Medical Systems, Inc.

By: /s/ Joseph K. Jachinowski                                By: /s/ Patrick W. Boyle
    ----------------------------------                           --------------------

Name: Joseph K. Jachinowski                                  Name: Patrick W. Boyle
     -----------------------------------                          -----------------

Title: CEO                                                   Title: President, OCS
       -----------------------------                                ------------------------------


Address:                                                     Address:
100 West Evelyn Avenue                                       4040 Nelson Avenue
Mountain View, California 94041                              Concord, California 94520

Tel 650-623-8800                                             Tel 925-602-8040
    --------------------------------                            ----------------------------------

Fax 650-623-8911                                             Fax 925-602-8041
    --------------------------------                            ----------------------------------





                                                          
4-25-01

                                                             /s/ Bernd Haetzel
                                                             VP Finance & Administration

                                                             4-25-01

                                       22



                    Exhibit A, Product and Training, with Pricing
                                       ***

- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***       ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                        ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                        ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***
- --------------------------------------------------------------------------------
   ***           ***                               ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------

***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.

IMPAC Medical Systems, Inc. Confidential


- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***       ***
- --------------------------------------------------------------------------------
   ***           ***                  ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***                         ***    ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***                               ***                     ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------

***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.

IMPAC Medical Systems, Inc. Confidential


- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***             ***     ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***                                ***
- --------------------------------------------------------------------------------
   ***                                ***
- --------------------------------------------------------------------------------

 Notes:
   1 ***



   2 ***

   3 ***

***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.

IMPAC Medical Systems, Inc. Confidential






                 Exhibit A, Product and Training, with Pricing
                                       ***

- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***       ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                        ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                        ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***
- --------------------------------------------------------------------------------
   ***           ***                               ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------

***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.

IMPAC Medical Systems, Inc. Confidential


- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***       ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***                         ***    ***
- --------------------------------------------------------------------------------
   ***           ***                                             ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***           ***
- --------------------------------------------------------------------------------
   ***           ***                               ***                     ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------

***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.

IMPAC Medical Systems, Inc. Confidential


- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***         ***         ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***                                  ***
- --------------------------------------------------------------------------------
   ***                                                                     ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***           ***           ***    ***          ***
- --------------------------------------------------------------------------------
   ***                                ***
- --------------------------------------------------------------------------------
   ***                                ***
- --------------------------------------------------------------------------------

 Notes:

    1 ***



    2 ***

    3 ***


***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.

IMPAC Medical Systems, Inc. Confidential















                                    EXHIBIT B

                          MINIMUM END-USER RESTRICTIONS

         Each End-User Agreement shall contain provisions at least as protective
of IMPAC as those set forth in this Exhibit B.

1.   Restrictions. End-User may not: (i) reproduce or copy any of the Products
     other than to make a reasonable number of copies for back-up and/or
     archival purposes; (ii) modify or create any derivative works of any of the
     Products; (iii) decompile, disassemble, reverse engineer, or otherwise
     attempt to derive the source code for any of the Products; (iv) disclose,
     redistribute, encumber, sell, rent, lease, sublicense, or otherwise
     transfer rights to any of the Products, except that End-User may transfer
     all of End-User's rights in such Products to a third party who agrees in
     writing to be bound by all of the provisions of this Agreement; or (v)
     remove or alter any trademark, logo, copyright or other proprietary
     notices, legends, symbols or labels in any of the Products.

2.   Ownership. Except for the licenses expressly set forth in this Agreement,
     all right, title and interest in and to the Products shall remain with
     Distributor and its licensor(s). End-User acknowledges such ownership and
     intellectual property rights and will not take any action to jeopardize,
     limit or interfere in any manner with Distributor's or its licensors'
     ownership of or rights with respect to the Products.

3.   Disclaimers. EXCEPT AS EXPRESSLY PROVIDED IN THIS AGREEMENT, THE PRODUCTS
     (INCLUDING WITHOUT LIMITATION THE RELATED DOCUMENTATION) ARE PROVIDED ON AN
     "AS IS" BASIS, WITHOUT WARRANTY OF ANY KIND, INCLUDING WITHOUT LIMITATION
     THE WARRANTIES THAT THEY ARE FREE OF DEFECTS, ERROR-FREE, MERCHANTABLE, FIT
     FOR A PARTICULAR PURPOSE OR NON-INFRINGING.

4.   Limitation of Liability. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW,
     IN NO EVENT WILL DISTRIBUTOR OR ITS LICENSORS BE LIABLE FOR ANY INDIRECT,
     SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF OR
     INABILITY TO USE THE PRODUCTS, INCLUDING, WITHOUT LIMITATION, DAMAGES FOR
     LOSS OF GOODWILL, WORK STOPPAGE, EQUIPMENT FAILURE OR MALFUNCTION, OR COST
     OF SUBSTITUTE GOODS OR SERVICES, EVEN IF ADVISED OF THE POSSIBILITY
     THEREOF, AND REGARDLESS OF THE LEGAL OR EQUITABLE THEORY (CONTRACT, TORT OR
     OTHERWISE) UPON WHICH THE CLAIM IS BASED.




                            [SIEMENS LOGO GOES HERE]
                                    EXHIBIT C
             AFFIDAVIT OF DESTRUCTION OR RE-REGISTRATION OF COMPUTER
                        SOFTWARE AND INDEMNITY AGREEMENT

THIS IS TO CERTIFY that the undersigned says that he is an authorized officer of
Siemens Medical Systems Oncology Care Systems, a DELAWARE corporation
("SMS-OCS"), and that SMS-OCS has discontinued the use of software ordered from
IMPAC Medical Systems, Inc., a CALIFORNIA corporation, ("IMPAC") which was
installed upon a CPU system for the purpose designated below.

The undersigned hereby represents that the statements made herein are made as an
inducement to IMPAC to accept this affidavit, to take the action designated
below, and to update its records accordingly as an acknowledgement of the
discontinuation of use of said software. The undersigned agrees as follows:

   1. To indemnify IMPAC against any losses or damages that IMPAC may in
      any way sustain, incur or become liable for as a consequence of the
      acceptance of this Affidavit and Indemnity Agreement.

   2. To take any other steps and to perform any and all further acts
      necessary to ensure that only one Copy of licensed software is in
      use. SMS-OCS hereby states that it has caused the previously
      registered IMPAC software to be erased and destroyed from said CPU
      system and disabled the program so that it may not be used by the
      owner of the said CPU system or by anyone else.


                  PURPOSE                                            ACTION
                  -------                                            ------
                                           
      a) [] NetWare license change             -  re-register existing software at no additional charge.
      b) [] DOS license change                 -  re-register existing software at no additional charge.
      c) [] Stand alone to network upgrade     -  re-register existing software at no additional charge.

                                                                 OR

   3. To take any other steps and to perform any and all further acts
      necessary to prevent any further use of said software. SMS-OCS
      hereby states that it has caused the IMPAC software to be erased and
      destroyed from said CPU systems and disabled the program so that it
      may not be used by the owner of the CPU system of by anyone else.



                          PURPOSE                                                     ACTION
                          -------                                                     ------
                                   
      a) [] Demonstration/testing     -  reduce total count of demonstration/testing licenses in use.
      b) [] Incorrect software order  -  issue credit or refund if payment for said software has been received

      Signed this  day of

      SIEMENS MEDICAL SYSTEMS ONCOLOGY CARE SYSTEMS, Inc.

      Signature:  _____________________________________________________________

      Name/Title: _____________________________________________________________

      Site/User: ____________________________   Old Registration Key:__________

                                                New Registration Key:__________

      Previous Software Installed:    New Software Installed (if applicable):

      _________________________________________________________________________

      _________________________________________________________________________

      _________________________________________________________________________


                                    Exhibit D

                        FORM OF CONFIDENTIALITY AGREEMENT

         THIS CONFIDENTIALITY AGREEMENT (the "Agreement") is entered into this
______ day of __________, 20__, by and between Siemens Medical Systems, Inc.,
the "Disclosing Party") and _________________________________________, (the
"Receiving Party") for the purpose of preventing the unauthorized disclosure of
Confidential Information (as defined below) of the Disclosing Party which may be
disclosed to the Receiving Party as an auditor retained in connection with an
audit of the Disclosing Party's books, records and employees pursuant to that
certain Software Distribution Agreement between Siemens Medical Systems, Inc.,
and IMPAC Medical Systems, Inc. ("the Distribution Agreement").

         For purposes of this Agreement, Confidential Information shall mean all
confidential or proprietary (written, recorded or oral) information or data (i)
marked or identified by the Disclosing Party as being confidential or
proprietary or (ii) which the Receiving Party should reasonably understand to be
confidential or proprietary. By way of example, Confidential Information
includes research, developmental, engineering, manufacturing, technical,
marketing, sales, financial, operating, performance, cost, business and process
information or data, know-how, and computer programming and other software and
software techniques.

         In consideration of the Disclosing Party's disclosure of Confidential
Information of the Receiving Party, the Receiving party hereby agrees as
follows:

         1. The Receiving Party shall hold and maintain the Confidential
Information in strict confidence and in trust for the sole and exclusive benefit
of the Disclosing Party.

         2. The Receiving party shall not, without the prior written approval of
the Disclosing Party, use for its own benefit, publish or otherwise disclose to
others, or permit the use by others for their benefit for to the detriment of
the Disclosing Party, any of the Confidential Information except only to the
extent that it is necessary for the Receiving Party to disclose any part of the
Confidential Information to a party to the Distribution Agreement in connection
with performing the Receiving Party's functions as an auditor pursuant to the
terms of the Distribution Agreement.

         3. The Receiving Party shall carefully restrict access to the
Confidential Information to those of its officers, directors, employees and
professional advisors who clearly need such access in order to participate on
behalf of the Receiving Party in the audit of the Disclosing Party's books,
records and employees as provided for in the Distribution Agreement. The
Receiving Party further warrants and represents that it will advise each of the
persons to whom it provides access to any of the Confidential Information
pursuant to the foregoing sentence that such persons are strictly prohibited
from making any use, publishing or otherwise disclosing to others or permitting
others to use for their benefit or to the detriment of the Disclosing Party, any
of the Confidential Information.

         4. This Agreement shall continue in full force and effect for a period
of two (2 ) years from the date hereof and the obligations of confidentiality
set forth herein shall survive in perpetuity, except that the Receiving Party's
obligations hereunder shall not extend to any of the




         Confidential Information which the Receiving Party can demonstrate (i)
was in the public domain on the date of this Agreement, (ii) comes into the
public domain after the date of this Agreement without fault of the Receiving
Party, or (iii) is rightfully received by Receiving Party from a party under no
duty of confidentiality to the Disclosing Party.

         5. The Receiving Party agrees that the Disclosing Party shall have the
right to apply to a court of competent jurisdiction for an order restraining any
disclosure or misappropriation of any of the Confidential Information in
violation of this Agreement and for such other relief as the Disclosing Party
shall deem appropriate, such right of the Disclosing Party to be in addition to
the remedies otherwise available to the Disclosing Party at law or in equity.

         6. The Receiving Party shall return to the Disclosing Party any and all
records, notes and other written, printed or tangible materials pertaining to
the Confidential Information immediately upon the written request of the
Disclosing Party.

         7. This Agreement and the Receiving Party's obligations hereunder shall
be binding upon the representatives, assigns and successors of the Receiving
Party and shall inure to the benefit of the assigns and successors of the
Disclosing Party.

         8.       This Agreement shall be governed by and construed in
accordance with the internal laws of the State of California.

         9. If any action at law or in equity is brought to enforce or interpret
the provisions of this Agreement, the prevailing party in such action shall be
entitled to reasonable attorney's fees.

         10. This Agreement constitutes the sole understanding of the parties
with respect to the subject matter hereof and may not be amended or modified
except in a writing signed by each of the parties.

         IN WITNESS WHEREOF, the parties hereto have entered into this Agreement
on the date set forth above.

Siemens Medical Systems, Inc.                            RECEIVING PARTY:

________________________                    ___________________________


By:______________________                   By:________________________

Its:_____________________                   Its:_______________________




                                  CONFIDENTIAL

                           IMPAC MEDICAL SYSTEMS, INC.

                               FIRST AMENDMENT TO
                         SOFTWARE DISTRIBUTION AGREEMENT

         This First Amendment (First Amendment) to the Software Distribution
Agreement (Agreement) is entered into by and between IMPAC Medical Systems,
Inc., a California corporation (IMPAC), and Siemens Medical Systems, Inc., a
Delaware corporation (Siemens).

                                   Background

         The parties entered into a Software Distribution Agreement on April 25,
2001 that provided for the distribution of IMPAC Products by Siemens. The
Agreement set out specific transfer prices for the Products that included
certain third-party products.

         The parties desire to amend and modify the Agreement to ***.

         Accordingly, the parties agree as follows:

1. The following sentence is added to the end of Section 3.1 of the Agreement:

         This limitation on price modification frequency and the cap on annual
         price increases shall not apply to ***.


2. Exhibit A to the Agreement is deleted in its entirety and is replaced with
the new Exhibit A attached to this First Amendment.


         In all other respects the Agreement shall remain unmodified and in full
force and effect. In the event of any inconsistency between the terms and
conditions of this First Amendment and the terms and conditions of the
Agreement, the terms and conditions of this First Amendment shall govern and
control.

         This First Amendment may be executed in two or more counterparts, each
of which shall be deemed an original, but all of which together will constitute
one and the same instrument.


         The parties have caused this First Amendment to be signed by their duly
authorized representatives.


*** 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.




IMPAC Medical Systems, Inc.                       Siemens Medical Systems, Inc.

By: /s/ Joseph K. Jachinowski                     By: /s/ Ajit Singh
    -----------------------------------               --------------

Name: Joseph K. Jachinowski                       Name: Ajit Singh
      ---------------------------------                 ----------

Title: CEO                                        Title: President, OCS
       --------------------------------                  --------------

Date: 9/23/01                                     Date: 9/13/01
      ---------------------------------                 -------

Address:                                          Address:
100 West Evelyn Avenue                            4040 Nelson Avenue
Mountain View, California 94041                   Concord, California 94520

Tel (650) 623-8800                                Tel (925) 602-8040

Fax (650) 623-8911                                Fax (925) 602-8041






IMPAC--Siemens First Amendment to Software Distribution Agreement 8-1-01    2

EX-10.2

                                                                    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.



       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.



    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
    the omitted portions.



    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.



           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.



Exhibit A                       US Oncology Sites



- ------------------------------------------------------------------------------------------------------------------------------------
     AZ            CO             Portland         ugene           WA               OK                    NY               NV
- ------------------------------------------------------------------------------------------------------------------------------------
                                                                                               
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
- ------------------------------------------------------------------------------------------------------------------------------------



- ------------------------------------------------------------------------------------------------------------------------------------
          TOPA                       IL               IN                  OH                      KS             MN          MO
- ------------------------------------------------------------------------------------------------------------------------------------
                                                                                                     
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




Exhibit B
                               US Oncology, Inc.
                         IMPAC Software Product Package

- --------------------------------------------------------------------------------

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

   ---------------------------------------------------------------

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


   ***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.



Exhibit C                   Hardware Product Package

                                      IMPAC
                                  ASP Hardware
                         Base System with View Station*



- --------------------------------------------------------------------------------------------
                 2/15/2002 Submission
- --------------------------------------------------------------------------------------------
                                                              Part #               Qnty
- --------------------------------------------------------------------------------------------
                                                                              
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            ***
- --------------------------------------------------------------------------------------------


*          ***

*** 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.



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.



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.



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
                                                                            1/10



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
                          T/800.623.8800 F/650.6238911
                                                                            2/10



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
                          T/800.623.8800 F/650.6238911
                                                                            3/10



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
                          T/800.623.8800 F/650.6238911                      4/10



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



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
                          T/800.623.8800 F/650.6238911                     6/10



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
                          T/800.623.8800 F/650.6238911                      7/10




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



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



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



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.

EX-10.3.1

                                                                  EXHIBIT 10.3.1

                                  ADDENDUM TWO

     The Lease made and entered into on September 1, 1999, by and between GORDON
A. CAMPBELL and MARIA LIGETI, TRUSTEES OF THE REVOCABLE LIVING TRUST DATED MARCH
23, 1987; HILLVIEW MANAGEMENT, INC.; AND IMPAC MEDICAL SYSTEMS AND SUBSIDIARY, a
California Corporation, is hereby Amended as follows:

Paragraph 2.01(b) shall be amended as follows:

     Tenant will pay full base rent of $118,201.40 effective as of May 7, 2000.

     Tenant will take occupancy on March 24, 2000.

     All other conditions remain.

TENANT:                     IMPAC MEDICAL SYSTEMS AND SUBSIDARY
                            A California Corporation


                            By    /s/ Joseph K. Jachinowski  3/23/00
                              --------------------------------------------------
                                  Joseph K. Jachinowski, President & CEO

LANDLORDS:                  GORDON CAMPBELL AND MARIA LIGETI,
                            TRUSTEES OF THE REVOCABLE LIVING TRUST
                            DATED MARCH 23, 1987


                            By    /s/ Maria Ligeti   3/23/00
                              --------------------------------------------------
                                  Maria Ligeti, Trustee

                            HILLVIEW MANAGEMENT, INC.
                            A California Corporation


                            By    /s/ George P. Eshoo  3/23/00
                              --------------------------------------------------
                                  George P. Eshoo
                                  Its: President