**Exhibit 31.1**

 

**RULE 13a-14(a)/15d-14(a) CERTIFICATION PURSUANT TO**

**SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002**

 

I, Brian Pratt, certifythat:

 

1.             I have reviewed thisQuarterly Report on Form 10-Q for the period ended September 30, 2010 ofPrimoris Services Corporation;

 

2.             Based on my knowledge, thisQuarterly Report does not contain any untrue statement of a material fact oromit to state a material fact necessary to make the statements made, in lightof the circumstances under which such statements were made, not misleading withrespect to the period covered by this Quarterly Report;

 

3.             Based on my knowledge, thefinancial statements, and other financial information included in thisQuarterly Report, fairly present in all material respects the financialcondition, results of operations and cash flows of the registrant as of, andfor, the periods presented in this Quarterly Report;

 

4.             The registrant’s othercertifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange ActRules 13a-15(e) and 15d-15(e)) and internal control over financialreporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))for the registrant and have:

 

(a)           Designed such disclosurecontrols and procedures, or caused such disclosure controls and procedures tobe designed under our supervision, to ensure that material information relatingto the registrant, including its consolidated subsidiaries, is made known to usby others within those entities, particularly during the period in which thisQuarterly Report is being prepared;

 

(b)           Designed such internalcontrol over financial reporting, or caused such internal control overfinancial reporting to be designed under our supervision, to provide reasonableassurance regarding the reliability of financial reporting and the preparationof financial statements for external purposes in accordance with generallyaccepted accounting principles;

 

(c)           Evaluated the effectivenessof the registrant’s disclosure controls and procedures and presented in thisQuarterly Report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this QuarterlyReport based on such evaluation; and

 

(d)           Disclosed in this QuarterlyReport any change in the registrant’s internal control over financial reportingthat occurred during the registrant’s most recent fiscal quarter that hasmaterially affected, or is reasonably likely to materially affect, theregistrant’s internal control over financial reporting; and

 

5.             The registrant’s othercertifying officer and I have disclosed, based on our most recent evaluation ofinternal control over financial reporting, to the registrant’s auditors and theaudit committee of the registrant’s board of directors (or persons performingthe equivalent functions):

 

(a)           All significant deficienciesand material weaknesses in the design or operation of internal control overfinancial reporting which are reasonably likely to adversely affect the registrant’sability to record, process, summarize and report financial information; and

 

(b)           Any fraud, whether or notmaterial, that involves management or other employees who have a significantrole in the registrant’s internal control over financial reporting.

 

Date:  November 9, 2010

 
| /s/ BRIAN PRATT                                                 |   |
|-----------------------------------------------------------------|--------|
| Brian Pratt                                                     |   |
| *Chairman  of the Board, Chief Executive Officer and President* |   |

 

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