Exhibit 3

                                SECOND AMENDMENT

                                       TO

                                RIGHTS AGREEMENT

                  SECOND AMENDMENT TO RIGHTS AGREEMENT (this "Amendment"), dated
as of August 17, 2001 by and among Varian Medical Systems, Inc., a Delaware
corporation (the "Company"), and First Chicago Trust Company of New York,
("First Chicago").

                              W I T N E S S E T H:


                  WHEREAS, the Company and First Chicago entered into a Rights
Agreement, dated as of November 20, 1998 and amended effective April 2, 1999
(the "Rights Agreement"), under which First Chicago, or its successors pursuant
to Section 4.2 of the Rights Agreement, was appointed the Rights Agent;

                  WHEREAS, the Board of Directors of the Company, pursuant to
Section 5.4 of the Rights Agreement, deems it appropriate to further amend the
Rights Agreement to adjust the Exercise Price of the Rights in order to
adequately protect the interests of holders of Rights;

                  NOW, THEREFORE, in consideration of the premises and the
mutual agreements herein set forth, the parties hereby agree as follows:

                  Section 1. Amendment of Rights Agreement. Effective as of
August 17, 2001 the Rights Agreement shall be, and hereby is, amended as
follows:

                  (a) Section 1.1 is hereby amended by deleting the dollar
amount "$110.00" in the definition of Exercise Price and substituting in lieu
thereof the dollar amount $420.00.

                  (b) Each reference in the Rights Agreement to "this
Agreement," and each use in the Rights Agreement of terms such as "herein,"
"hereof" and "hereunder," shall mean and be a reference to the Rights Agreement
as amended hereby.

                  Section 2. Full Force and Effect. Except as specifically
provided in this Amendment, the Rights Agreement shall remain in full force and
effect and shall in no way be amended, modified or affected.

                  Section 3. Governing Law. The Rights Agreement and this
Amendment shall be deemed to be contracts made under the laws of the State of
Delaware and for all purposes shall be governed by and construed and enforced in
accordance with the laws of such state applicable to contracts to be made and
performed entirely within such state.

                  Section 4. Definitions. Terms used in this Amendment and not
defined herein shall have the meanings assigned to such terms by the Rights
Agreement.

                  Section 5. Severability. If any term or provision of this
Amendment or the application thereof to any circumstance shall, in any
jurisdiction and to any extent, be invalid or unenforceable, such term or
provision shall be ineffective as to such jurisdiction to the extent of such
invalidity or unenforceability without invalidation or rendering unenforceable
the remaining terms and provisions of this Amendment or the application of such
term or provision to circumstances other than those as to which it is held
invalid or unenforceable.

                  Section 6. Counterparts. This Amendment may be executed in any
number of counterparts and each of such counterparts shall for all purposes be
deemed to be an original, and all such counterparts shall together constitute
one and the same instrument.

                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be duly executed by officers thereof thereunto duly authorized, all
as of the day and year first above written.

                                        VARIAN MEDICAL SYSTEMS, INC.

                                        By: /s/ Joseph B. Phair
                                        ----------------------------------------
                                        Name:    Joseph B. Phair

                                        Title:   Vice President, Administration,
                                                 General Counsel and Secretary


                                        FIRST CHICAGO TRUST COMPANY OF NEW YORK

                                        By:  /s/ Anthony Milo
                                        ----------------------------------------
                                        Name:    Anthony Milo
                                        Title:   Managing Director


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