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                                                                    EXHIBIT 31.1

           PRINCIPAL EXECUTIVE OFFICER AND PRINCIPAL FINANCIAL OFFICER
                 REQUIRED BY RULE 13A-14(A) OR RULE 15D-14(A) OF
   THE SECURITIES EXCHANGE ACT OF 1934, AS ADOPTED PURSUANT TO SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Nigel P. Ekern, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Net Perceptions, Inc.;

2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the registrant as
of, and for, the periods presented in this report;

4. I am responsible for establishing and maintaining disclosure 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 my supervision, to
     ensure that material information relating to the registrant, including its
     consolidated subsidiaries, is made known to me by others within those
     entities, particularly during the period in which this report is being
     prepared;

     (b) Evaluated the effectiveness of the registrant's disclosure controls and
     procedures and presented in this report my conclusions about the
     effectiveness of the disclosure controls and procedures, as of the end of
     the period covered by this report based on such evaluation; and

     (d) Disclosed in this report any change in the registrant's internal
     control over financial reporting that occurred during the registrant's most
     recent fiscal quarter (the registrant's fourth fiscal quarter in the case
     of an annual report) that has materially affected, or is reasonably likely
     to materially affect, the registrant's internal control over financial
     reporting; and

5. I have disclosed, based on my most recent evaluation of internal control over
financial reporting, to the registrant's auditors and the audit committee of the
registrant's board of directors (or persons performing the equivalent
functions):

     (a) All significant deficiencies and material weaknesses in the design or
     operation of internal control over financial reporting which are reasonably
     likely to adversely affect the registrant's ability to record, process,
     summarize and report financial information; and

     (b) Any fraud, whether or not material, that involves management or other
     employees who have a significant role in the registrant's internal control
     over financial reporting.

Date: August 16, 2004

                                                /s/ Nigel P. Ekern
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                                                Nigel P. Ekern
                                                Chief Administrative Officer
                                                (Principal Executive Officer and
                                                Principal Financial Officer)
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