EXHIBIT        31.1

 

**CERTIFICATIONS**

 

I, John R.        Irwin, certify that:

 

|   | 1. | I have reviewed this annual report on Form 10-K of Atwood                        Oceanics, Inc.; |
|--------|----|--------------------------------------------------------------------------------------------------|

 

|   | 2. | Based on my knowledge, this report does not contain any                        untrue statement of a material fact or omit to state a material fact                        necessary to make the statements made, in light of the circumstances under                        which such statements were made, not misleading with respect to the period                        covered by this report; |
|--------|----|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

 

|   | 3. | Based on my knowledge, the financial statements, and other                        financial information included in this report, fairly present in all                        material respects the financial condition, results of operations and cash                        flows of the registrant as of, and for, the periods presented in this                        report; |
|--------|----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

 

|   | 4. | The registrant's other certifying officer(s) and I are                        responsible for establishing and maintaining disclosure controls and                        procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and                        internal control over financial reporting (as defined in Exchange Act Rules                        13a-15(f) and 15d-15(f)) for the registrant and have: |
|--------|----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

 

(a) Designed such disclosure controls and procedures, or caused such        disclosure controls and procedures to be designed under our supervision, to ensure that        material information relating to the registrant, including its consolidated subsidiaries,        is made known to us by others within those entities, particularly during the period in        which this report is being prepared;

         

(b) Designed such internal control over financial reporting, or caused such        internal control over financial reporting to be designed under our supervision, to provide        reasonable assurance regarding the reliability of financial reporting and the preparation        of financial statements for external purposes in accordance with generally accepted        accounting principles;

         

(c) Evaluated the effectiveness of the registrant's disclosure controls and        procedures and presented in this report our conclusions about the effectiveness of the        disclosure controls and procedures, as of the end of the period covered by this report        based on such evaluation; and

         

(d) Disclosed in this report any change in the registrant's internal control        over financial reporting that occurred during the registrant's most recent

fiscal quarter (the registrant's fourth fiscal quarter in the case of an        annual report) that has materially affected, or is reasonably likely to materially affect,        the registrant's internal control over financial reporting; and

         

|   | 5. | The registrant's other certifying officer(s) and I have                        disclosed, based on our most recent evaluation of internal control over                        financial reporting, to the registrant's auditors and the audit committee                        of the registrant's board of directors (or persons performing the                        equivalent functions): |
|--------|----|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

         

(a) All significant deficiencies and material weaknesses in the design or        operation of internal control over financial reporting which are reasonably likely to        adversely affect the registrant's ability to record, process, summarize and report        financial information; and

         

(b) Any fraud, whether or not material, that involves management or other        employees who have a significant role in the registrant's internal control over financial        reporting.

         

Date:        November 29, 2007

 

/S/ JOHN R. IRWIN

John R. Irwin

Chief Executive Officer