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Exhibit 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-4) and related joint prospectus/proxy statement
of Rational Software Corporation for the registration of shares of its common
stock and to the incorporation by reference therein of our report dated April
18, 2000, with respect to the consolidated financial statements and schedule of
Rational Software Corporation included in its Annual Report (Form 10-K) for the
year ended March 31, 2000 filed with the Securities and Exchange Commission.
/s/ Ernst & Young LLP
Palo Alto, California
December 29, 2000
