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EXHIBIT 23.1
INDEPENDENT AUDITORS' CONSENT
We consent to the incorporation by reference in this Registration Statement
of Investors Financial Services Corp. on Form S-3 of our reports dated
February 11, 2000, appearing in the Annual Report on Form 10-K of Investors
Financial Services Corp. for the year ended December 31, 1999 and to the
reference to us under the heading "Experts" in the Prospectus, which is part of
this Registration Statement.
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<C> <S>
/s/ DELOITTE & TOUCHE LLP
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Boston, Massachusetts
December 4, 2000
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