# **Exhibit31.1**

**CERTIFICATIONS**

 

I, Kevin J. Sheehan, Chairman and Chief ExecutiveOfficer, certify that:

 

1.               I have reviewed this Quarterly Report on Form10-Q of Investors Financial Services Corp.;

 

2.               Based on myknowledge, this report does not contain any untrue statement of a material factor omit to state a material fact necessary to make the statements made, inlight of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report;

 

3.               Based on myknowledge, the financial statements, and other financial information includedin this report, fairly present in all material respects the financialcondition, results of operations and cash flows of the registrant as of, andfor, the periods presented in this report;

 

4.               The registrant’sother certifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e)and 15d-15(e)) for the registrant and have:

 

(a)          Designed such disclosure controls and procedures,or caused such disclosure controls and procedures to be designed under oursupervision, to ensure that material information relating to the registrant,including its consolidated subsidiaries, is made known to us by others withinthose entities, particularly during the period in which this report is beingprepared;

 

(b)         [Paragraph omitted in accordance with SECtransition instruction contained in SEC Release 34-47986.]

 

(c)          Evaluated the effectiveness of the registrant’sdisclosure controls and procedures and presented in this report our conclusionsabout the effectiveness of the disclosure controls and procedures, as of theend of the period covered by this report based on such evaluation; and

 

(d)         Disclosed in this reportany change in the registrant’s internal control over financial reporting thatoccurred during the registrant’s most recent fiscal quarter (the registrant’sfourth fiscal quarter in the case of an annual report) that has materiallyaffected, or is reasonably likely to materially affect, the registrant’sinternal control over financial reporting; and

 

5.               The registrant’sother certifying officer and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to the registrant’sauditors and the audit committee of the registrant’s board of directors (orpersons performing the equivalent functions):

 

(a)          All significant deficiencies and materialweaknesses in the design or operation of internal control over financial reportingwhich are reasonably likely to adversely affect the registrant’s ability torecord, process, summarize and report financial information; and

 

(b)         Any fraud, whether or not material, that involvesmanagement or other employees who have a significant role in the registrant’sinternal control over financial reporting.

 

Date: August 11, 2003

 
|   | /s/ Kevin J.Sheehan                   |   |
|--------|---------------------------------------|--------|
|   | Chairman and Chief Executive  Officer |

 

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