Exhibit 31.2

# CERTIFICATIONS

I, Samuel E. Reinkensmeyer, certify
that: 1. I have reviewed this Form 10-Q of CNS, 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;
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|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;
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|4. |  | The registrants other certifying officer(s) and I are 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:
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| | (a)
Designed such disclosure controls and procedures, or caused such disclosure controls and
procedures to be designed under our supervision, to ensure that material information
relating to the registrant, including its consolidated subsidiaries, is made known to us
by others within those entities, particularly during the period in which this report is
being prepared;
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| | (b)
Evaluated the effectiveness of the registrants disclosure controls and procedures
and presented in this report our 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
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| | (c) 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
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|5. |  | The registrants other certifying officer(s) and I have disclosed, based on
               our 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):
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| | (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
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| | (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.
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Date: November 6, 2003

/s/ Samuel E. ReinkensmeyerSamuel E. ReinkensmeyerVice President of Finance, Chief Financial Officer and Treasurer

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