Exhibit 31.1
CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER
I, Steven W. Alesio, certify that:
1. I have reviewed this Quarterly Report on Form 10-Q/A of The Dun & Bradstreet Corporation; and
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.
| By: | /s/ Steven W. Alesio | |
| Steven W. Alesio | ||
| Chairman and Chief Executive Officer | ||
| Date: | October 8, 2009 | |
