EXHIBIT 23.3
                                                                    ------------


                        CONSENT OF INDEPENDENT AUDITORS

We consent to the incorporation by reference in this Registration Statement on
Form S-8 pertaining to the 1997 Employee Stock Purchase Plan of Peritus Software
Services, Inc. of our report dated October 29, 1997, with respect to the
financial statements of Millennium Dynamics, Inc. as of December 31, 1995 and
1996 and September 30, 1997 and for each of the two years ended December 31,
1996 and for the nine months ended September 30, 1997, included in the Peritus
Software Services, Inc. Current Report on Form 8-K/A, filed with the Securities
and Exchange Commission on February 17, 1998.


                              /s/ Ernst & Young LLP
                              Ernst & Young LLP


Cincinnati, Ohio
July 22, 1998