POWER OF ATTORNEY LETTER

POWER OF ATTORNEY

Know all by these present, that the undersigned hereby constitutes and
appoints each of Dana A. Gordon and Vincent A. Mercaldi, signing singly,
the undersigned's true and lawful attorney-in-fact to:

1 execute for and on behalf of the undersigned, in the undersigned's cap
acity as a director and/or officer of Quanta Services,
Inc. the "Company", Forms 3, 4, and 5 in accordance
with Section 16(a) of the Securities Exchange Act of
1934 and the rules thereunder;

2 do and perform any and all acts for and on behalf of the undersigned w
hich may be necessary or desirable to complete and
execute any such Form 3, 4, or 5, complete and execute
any amendment or amendments thereto, and timely file
such form with the United States 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 by, the
undersigned, it being understood that the documents
executed by such attorney-in-fact on behalf of the
undersigned pursuant to this Power of Attorney shall be
in such form and shall contain such terms and
conditions as such attorney in fact may approve in such
attorney in fact's discretion.

The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever
requisite, necessary, or proper to be done in the exercise of any
of the rights and powers herein granted, as fully to all intents
and purposes as the undersigned might or could do if personally
present, with full power of substitution or revocation, hereby
ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do
or cause to be done by virtue of this power of attorney and the
rights and powers herein granted. The undersigned acknowledges
that the foregoing attorneys-in-fact, in serving in such capacity
at the request of the undersigned, are not assuming, nor is the
Company assuming, any of the undersigned's responsibilities to
comply with Section 16 of the Securities Exchange Act of 1934.
This Power of Attorney shall remain in full force and effect until the undersign
ed is no longer required to file Forms 3, 4, and 5 with respect
to the undersigned's holdings of and transactions in securities
issued by the Company, unless earlier revoked by the undersigned
in a signed writing delivered to the foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 27tn day of May 2005.


/s/ Vincent D Foster