

                                                                  Exhibit 23.1 

                       CONSENT OF INDEPENDENT AUDITORS 

   We consent to the reference to our firm under the captions "Experts" and 
"Selected Consolidated Financial Data" and to the use of our report dated May 
6, 1996 (except for Notes 10 and 11, as to which the date is      , 1996), in 
the Registration Statement on Form S-1 and the related Prospectus of 
Pegasystems Inc. for the registration of 3,910,000 shares of its common 
stock. 

   Our audits also included the financial statement schedule of Pegasystems 
Inc. located at Exhibit 99.1. This schedule is the responsibility of the 
Company's management. Our responsibility is to express an opinion based on 
our audits. In our opinion, the financial statement schedule referred to 
above, when considered in relation to the basic financial statements taken as 
a whole, presents fairly in all material respects the information set forth 
therein. 

ERNST & YOUNG LLP 
Boston, Massachusetts 

   The foregoing consent is in the form that will be signed upon the 
completion of the restatement of capital accounts described in Note 10 to the 
financial statements. 

ERNST & YOUNG LLP 
Boston, Massachusetts 
May 14, 1996 

