I, the
undersigned, do hereby make, constitute and appoint Timothy E. Guertin, Elisha
W. Finney and John W. Kuo, and each of them, my true and lawful
attorneys-in-fact and agents, each with power of substitution, in any or all of
my offices and capacities with Varian Medical Systems, Inc. as shown below, to
execute for me and on my behalf a registration statement on Form S-8 (the
“Registration Statement”) and any and all amendments and supplements thereto,
including post-effective amendments, relating to the Varian Medical Systems,
Inc. Second Amended and Restated 2005 Omnibus Stock Plan and to file the
Registration Statement, with all exhibits thereto, and any other documents in
connection therewith, with the Securities and Exchange Commission pursuant to
the Securities Act of 1933, as amended, and the rules and regulations
promulgated thereunder, and do hereby grant unto said attorneys-in-fact and
agents full power and authority to do and perform each and every act and thing
requisite and necessary to be done, as fully to all intents and purposes as the
undersigned might or could do in person, and ratify and confirm all that said
attorneys-in-fact and agents, or their substitutes, may lawfully do or cause to
be done by virtue hereof.