Exhibit 31.1

# CERTIFICATION PURSUANT
TO SECTION 302 (a) OF THE SARBANES  OXLEY ACT OF 2002

I, Charles W. Berger, Chief Executive
Officer of Nuance Communications, Inc. certify that:

|1.                                                                                                                                                                                                                                                                                                                                                                                                      | I have reviewed this quarterly
report of Nuance communications, Inc. on Form 10-Q;                                                                                                                                                                                                                                          
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|                                                                                                                                                                                                                                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                                                             
|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)) 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)   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                                                                                                    
|                                                                                                                                                                                                                                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                                                             
|(c)   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.                                                                                                                                                                                                              

| |  | /s/ Charles W. Berger                                   
| |  | --------------------------------------------------------
| |  | Charles W. Berger ,President and Chief Executive Officer
| |  | August 6, 2004