| EXHIBIT                31.1                              |
|----------------------------------------------------------|
|                                                     |
| I,                Michael W. Laphen, certify that:  |
|                                                     | 1. | I                have reviewed this quarterly report on Form 10-Q of Computer Sciences                Corporation;  |
|                                                     | 2. | Based                on my knowledge, this quarterly 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 quarterly report;  |
|                                                     | 3. | Based                on my knowledge, the consolidated financial statements, and other                financial information included in this quarterly 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                quarterly report;  |
|                                                     | 4. | The                registrant’s other certifying officers 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 15-d-15(f)) for the registrant and we 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 quarterly                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 evaluations; and  |
|                                                     |   | d) | Disclosed                in this report any change in the registrant’s internal control over                financial reporting that occurred during the registrant’s second fiscal                quarter 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 officers 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 registrant’s board of                directors (or persons performing the equivalent function):  |
|                                                     |   | 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, summarized 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                controls over financial reporting.  |

| Date:                January 11, 2008 | By:    |  /s/                Michael W.                Laphen                                     |
|---------------------------------------|--------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|                                  |   |      Michael                W. Laphen                                                                                                                                                                                                                    |
|                                  |   |      Chairman                and Chief Executive                Officer                                                                                                                                                                                  |