**Exhibit 31.1**

**CERTIFICATE OF THE CHIEF EXECUTIVE OFFICER**

I, the Chief Executive Officer, of Witness Systems, Inc.(the “registrant”), certify that:

1.    I have reviewedthis report on Form 10-Q of the registrant for the quarter ended September 30,2005;

2.    Based on myknowledge, this report does not contain any untrue statement of a material factor omit to state a material fact necessary to make the statements made, inlight of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report;

3.    Based on myknowledge, the financial statements, and other financial information includedin this 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 report;

4.    The registrant’sother certifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as defined inExchange Act Rules 13a-15(f) and 15d-15(f))  for theregistrant and have:

(a)         designedsuch disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

(b)         Designedsuch internal control over financial reporting, or caused such internal controlover financial reporting to be designed under our supervision, to providereasonable assurance regarding the reliability of financial reporting and thepreparation of financial statements for external purposes in accordance withgenerally accepted accounting principles;

(c)         evaluatedthe effectiveness of the registrant’s disclosures controls and procedures andpresented in this report our conclusions about the effectiveness of thedisclosure controls and procedures, as of the end of the period covered by thisreport based on such evaluation; and

(d)         disclosed inthis report any change in the registrant’s internal control over financialreporting that occurred during the registrant’s most recent fiscal quarter thathas materially affected, or is reasonably likely to materially affect, theregistrant’s internal control over financial reporting.

5.    The registrant’sother certifying officer and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to the registrant’sauditors and the audit committee of the registrant’s board of directors:

(a)         allsignificant deficiencies and material weaknesses in the design or operation ofinternal control over financial reporting which are reasonably likely toadversely affect the registrant’s ability to record, process, summarize andreport financial information; and

(b)         anyfraud, whether or not material, that involves management or other employees whohave a significant role in the registrant’s internal controls over financialreporting.
| Dated: November 7, 2005 |   |                                                  |
|------------------------------|--------|-------------------------------------------------------|
|                         | BY:    | /s/  DAVID  B. GOULD                        |
|                         |   | David B. Gould                                        |
|                         |   | *Chairman of the Board and   Chief Executive Officer* |

 

1

----