Power of Attorney

I, Timothy E. Guertin, hereby constitute and appoint Elisha
W. Finney, Crisanto C. Raimundo, Franco N. Palomba,
Tai-Yun Chen, John W. Kuo, Kimberley E. Henningsen,
Mary O'Byrne, Alan D. Palter, Keith G. Askoff,
S. Andrew Motozaki, Heather F. Harner, and each of them
individually, as my true and lawful attorney-in-fact to:

1. Complete and execute on my behalf as an officer and/or
director of Varian Medical Systems, Inc. (the "Company")
any Forms 3, 4, or 5, and any amendment thereto,
required to be filed by me under Section 16(a) of the Securities
Exchange Act of 1934 and the rules and regulations thereunder.

2. Do and perform any and all acts for and on my behalf which
may be necessary or desirable to complete any such
Form 3, 4 or 5, and any amendment thereto, and timely
file such form or amended form with the U.S. Securities and
Exchange Commission and any stock exchange or similar
authority; and

3. Take any other action of any type whatsoever in connection
with the foregoing, which in the opinion of such
attorney-in-fact may be of benefit to, in the best interest of,
or legally required of me, it being understood that the documents
executed by such attorney-in-fact on my behalf pursuant to this
Power of Attorney shall be in such form and shall contain such
information as such attorney-in-fact may approve
in such attorney-in-fact's discretion.

I hereby grant to each of such attorneys-in-fact full power and
authority to do and perform any and every act which is necessary
or desirable to be done in the exercise of any of the powers
and authority granted in this Power of Attorney, with full power
of substitution and revocation, and  I ratify and confirm every
act that such attorney-in-fact lawfully performs or causes to be
done by virtue of this Power of Attorney and the powers
and authority granted herein.

I acknowledge that the attorneys-in-fact appointed in this
Power of Attorney, in serving in such capacity at my request,
are not assuming, and the Company is not assuming, any of my
responsibilities to comply with Section 16 of the Securities
and Exchange Act of 1934 or the rules or regulations thereunder.

This Power of Attorney shall remain in full force and effect until
I am no longer required to file Forms 3, 4 or 5 with respect to my
holding or transactions in securities issued by the Company, unless
I earlier revoke this Power of Attorney in a signed writing
delivered to the foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has executed this power of
attorney as of this 11th day of December, 2006 at Palo Alto,
California.

					/s/ Timothy E. Guertin
					_______________________
					Timothy E. Guertin