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Exhibit 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENDT AUDITORS
We consent to the reference of our firm under the caption "Experts" in Amendment
No. 1 to the Registration Statement (Form S-3, No. 333-36128) and related
Prospectus of Rational Software Corporation for the registration of $500,000,000
of 5% Subordinate Notes due February 1, 2007 and 6,998,880 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
July 19, 2000
