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Exhibit 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference of our firm under the caption "Independent Auditors"
in Amendment No. 1 to the Registration Statement (Form S-3, No. 333-37506) and
related Prospectus of Rational Software Corporation for the registration of
371,385 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
