Attached files
Exhibit 31.1
I, Alan Trefler, certify that:
| 1. | I have reviewed this Annual Report on Form 10-K/A of Pegasystems 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; |
Date: April 29, 2011
| /s/ ALAN TREFLER |
| Chairman and Chief Executive Officer (principal executive officer) |