SecProbe.io

UNITED STATES
SECURITIES AND E XCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010
         DIVISION OF
CORPORATION FINANCE

June 22, 2007

Mail Stop 7010

By U.S. Mail and facsimile to (713) 629-7676

Tana L. Pool
Vice President and General Counsel
Quanta Services, Inc.
1360 Post Oak Boulevard, Suite 2100
Houston, Texas 77056

Re:  Quanta Services, Inc.
 Amendment No. 1 to Registrati on Statement on Form S-4
Filed May 29, 2007
 File No. 333-142279
  Quanta Services, Inc., Form  10-K for the year ended 12/31/2006
Filed February 28, 2007
File No. 001-13831

Dear Ms. Pool:

We have reviewed your filings and have the following comments.  We welcome
any questions you may have about our comments or any other aspect of  our review.  Feel
free to call us at the telephone numbers  listed at the end of this letter.

General

1. We note your response to comment 2 of our letter dated May 17, 2007.  Please
advise us as to why the pr ojections are not material.

Comparative Quanta and Infrasource Market Price Data, page 23

2. Please provide equivalent per share data  for InfraSource stock as of March 16,
2007, as required by Item 3(g) of Form S-4.

The Merger, page 33
Background of the Merger, page 33

3. We note your response to comment 17 of our letter dated May 17, 2007.  Please
revise your disclosure regarding the December 8, 2005, meeting to clarify that no

Tana L. Pool
Quanta Services, Inc.
June 22, 2007 Page 2
specific acquisition proposal was made at  that time.  Please also revise your
discussion to disclose the parameters of the “possible acquisition of InfraSource by Quanta” that were discu ssed at the board meeting.

4. We note your response to comment 19 of our letter dated May 17, 2007.  Please revise your discussion to disclose that you were not involved in  discussions with
any alternative parties to Quanta after February 2006.

Opinion of Quanta’s Financial Advisor, page 46
Selected Company Analysis, page 50

5. We note your response to comment 26 of our letter dated May 17, 2007.  Please revise your discussion to disclose whet her other companies meeting the stated
criteria (publicly traded, similar indust ry with similar lines of business, and
market value between $550 million and $1.1 billion) were identified by Credit
Suisse in its analysis.  If so, please revise to name these companies and to disclose
why each was determined to be inco mparable to InfraSource or Quanta.

Opinion of InfraSource’s Financial Advisor, page 51
Analysis of InfraSource, page 53
Comparable Public Companies Analysis, page 54

6. Please respond to prior comment 26 with  respect to the comparable public
companies analysis performed by Citigroup in its evaluation of InfraSource.

Analysis of Quanta, page 55
Comparable Public Companies Analysis, page 55

7. We note your response to comment 26 of our  earlier comment letter with respect
to Citigroup’s comparable public companie s analysis of Quanta.  Please briefly
expand the discussion of Quanta’s unique characteristics that set it apart from the
companies included in Citigroup’s analysis  of InfraSource.  In addition, please
briefly discuss the utility  of a comparable public companies analysis that
evaluates only the part ies to the transaction.

Discounted Cash Flow Analysis, page 56

8. We note the statement that the selected  terminal EBITDA multiple range “was
based on the historical and current ra nge of multiples for publicly traded
companies.”  Please revise to clarif y whether the companies included in
calculating the range were the same as in the Comparable Public Companies Analysis or in another analysis perfor med by Citigroup.  If companies other than
InfraSource and Quanta were used, pleas e briefly address why such companies

Tana L. Pool
Quanta Services, Inc.
June 22, 2007 Page 3
terminal 2011E EBITDA multiples were useful to this analysis in light of such companies’ exclusion from the Comparable Public Companies Analysis due to “Quanta’s unique growth characteristic s, operations profile and end markets
served.”

Financial Statements
Notes to Unaudited Pro Forma combined Financial Statements
Note 2(a) – Purchase Price, page F-6

9. We note your response to our previous co mment 38 and appreciate the additional
information about acquired backlog.  We have the following additional comments:
• Pro forma Note 2(f) states that the acquired backlog has a weighted
average life of 2.28 years.  However, we read on page 6 of InfraSource’s
December 31, 2006 Form 10-K that they expected to complete about two-
thirds of their backlog during 2007.  Please tell us whether your
calculation of weighted average lif e for backlog differs from what
InfraSource relied upon in creating its 10-K disclosure, and if so, please
explain how and why.  In this regard , we read in your response that you
assigned a 19 year useful life to acquired backlog related to Telecommunications Services, and it is  unclear to us why such a long life
would be appropriate.
• Please explain to us in more detail how you considered InfraSource’s
master service agreements in calc ulating acquired backlog.  If your
methodology differs from the disclosure s on page 6 of InfraSource’s 10-K,
please explain how and why.  In this regard, we note your response to our
prior comment 42.
• Please provide us with a more detail ed explanation of how you calculated
the future cash flows associated w ith InfraSource’s backlog.  If your
valuation included any consideratio n of whether the acquired backlog
contracts were favorable or unfavor able compared to the market or
compared to “normal” margins, pleas e explain this to us in reasonable
detail.  Refer to paragraphs B171 through B174 of SFAS 141.

10. We note your response to prior co mments 38 and 39 concerning acquired
customer relationships and have the following comments:
• We read in your response that you exp ect the estimated attrition rates of
InfraSource’s customers to be “relatively low.”  Please explain to us in
more detail how you estimated this at trition rate, including whether it is
based on InfraSource’s historic attrition rate.
• Please provide us with a more detail ed explanation of how you calculated
the future cash flows associated with InfraSource’s customer relationships.
If your valuation included any consider ation of whether the resulting cash
flows were favorable or unfavorable compared to the market or compared

Tana L. Pool
Quanta Services, Inc.
June 22, 2007 Page 4
to “normal” margins, please explai n this to us in more detail.
• Please tell us whether you and InfraS ource have any overlap in customers,
and if so, please tell us how or if th is overlap affected your valuation of
acquired customer relationships.  Plea se refer to the guidance on valuing
customer related intangible assets in  Chad Kokenge’s speech at the 2003
AICPA National Conference on Curren t SEC Developments, available on
our website at www.sec.gov/news/speech/spch121103cak.htm, and Pam Schlosser’s speech at the 2005 AICP A National Conference on Current
SEC and PCAOB Developments, available on our website at www.sec.gov/news/speech/spch120505ps.htm.

11. We read in Note 1 to InfraSource’s D ecember 31, 2006, financial statements that
InfraSource’s historic intangible assets include acquired volume agreements.
Please tell us if or how these volume agr eements are included in your valuation of
InfraSource’s backlog or other customer relationships.

Item 22. Undertakings, page II-3

12. We note your response to comment 41 of our letter dated May 17, 2007.  Please revise to also provide the undertaking re quired by Items 512(a)(5)(ii) and (6) of
Regulation S-K.

Quanta Services, Inc., Form 10-K for the year ended 12/31/2006
Management’s Discussion and Analysis
Results of Operations, page 27

13. We note your response to our prior comme nt 44.  Since you state that you do not
separately track gross margins for each of  your electric power and gas customers,
telecommunications and cable television cu stomers, and ancillary services, if you
provide disclosure in future filings similar to that provided in your 10-K such that you separately address the gross margin s for these types of customers and
services, please revise to briefly explain how you derived your information on gross margins.  We believe this provid es important context to your readers.

Critical Accounting Policies – Valuation of Intangibles and Long-Lived Assets, page 36

14. We note your response to our prior comment  47.  Please refer to paragraph 47 of
SFAS 142 and to our Release 33-8350.  Your 2006 impairment of goodwill had a
significant impact on your income statemen t and therefore merits a reasonably
detailed explanation to your investors.  Revise future filings, either here or in the
footnotes to your financial statements, to provide greater context around this
impairment and more insight into whether or how this impairment impacts the likelihood of future impairments.  We continue to believe that it provides useful

Tana L. Pool
Quanta Services, Inc.
June 22, 2007 Page 5
information to your readers to disclose  that $30.2 million of goodwill remains at
this reporting unit and to briefly ex plain why that goodwill balance was not
impacted by the current impairment.  Give n your disclosure at the top of page 37
and in Note 2 to your financial statemen ts that the impairment was associated
with a business that has hi storically served the ca ble television industry, we
continue to believe that it provides useful information to your readers to provide
context as to whether management belie ves the current impairment signals an
increased likelihood of future similar im pairments at your other businesses that
serve the cable television i ndustry.  In this regard, information similar to that
provided in your response concerning the other industries served by these
reporting units would appear appr opriate for this disclosure.

Notes to Consolidated Financial Statements
Note 2 – Summary of Significant Accounti ng Policies – Revenue Recognition, page 52

15. We note your response to our prior comment  49 and the disclosures in your 10-K.
Based on your response, it a ppears that you recognize re venue for non-fixed price
design and/or installation contracts as  services are provided and not under the
percentage of completion method.  Furt hermore, the final sentence of your
response appears to indicat e that when you recognize re venue as services are
provided, you may calculate the amount of revenue to be recognized using some
form of input-based approach, such as co sts or time and materials.  Since you are
not accounting for these non-fixed pri ce construction contracts under the
percentage of completio n method, please help us to understand how you
determined that it was appropriate to use an input-based approach to measure
revenue recognition, and the accounting guidance that you are relying upon.
Refer to Section 2(F)(2) of our Outline  of Current Accounting and Disclosure
Issues, available on our website at
www.sec.gov/divisions/corpfin /cfacctdisclosureissues.pdf .

16. Your response to our prior comment 49 also appears to indicate that you
recognize revenue from maintenance contra cts as services are provided, and that
you may measure this using some form of input-based approach, such as costs or
time and materials.  It is unclear to us how you determin ed that it was appropriate
to use an input-based approach to measure revenue recognition for maintenance services.  Refer to Section 2(F)(2) of  our Outline of Current Accounting and
Disclosure Issues, available on our website at
www.sec.gov/divisions/corpfin /cfacctdisclosureissues.pdf .  Please advise, or
demonstrate to us that there is no mate rial difference between this method and
measuring revenues using proportional performance or output-based measures, and revise your accounting policy in future filings.

17. We read in your response to our prior comment 49 that you enter into contracts
that contain both installation and maintenan ce obligations.  Please explain to us in

Tana L. Pool
Quanta Services, Inc.
June 22, 2007 Page 6
more detail how you determine the amount  of revenue related to each and the
accounting guidance that you are relying upon.

18. We read in your response to our pr ior comment 50 that substantially all
significant materials on contracts th at you account for under percentage of
completion are provided by the customer.  Please revise your accounting policy in future filings to disclose this fact and to clarify whether these customer-furnished materials are included in your contract revenues and costs.  Refer to paragraph 60 of SOP 81-1.

You may contact Mindy Hooker, Staff Acc ountant, at (202) 551-3732 or Jennifer
Thompson, Senior Staff Account ant, at (202) 551-3737 if yo u have questions regarding
comments on the financial statements and rela ted matters.  Please contact Matt Franker,
Staff Attorney, at (202) 551-3749  or Andy Schoeffler, Senior  Staff Attorney, at (202) 551-
3748 with any other questions.  Alternativel y, you may contact me  at (202) 551-3760.

Sincerely,

Pamela A. Long
Assistant Director

cc: Christine B. LaFollette ( via facsimile  713/236-0822)
 Mark Zvonkovic
 John Goodgame
Akin Gump Strauss Hauer & Feld LLP
1111 Louisiana Street, 44th Floor
Houston, Texas 77002