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                                                                 Exhibit (31)(a)


                        CERTIFICATION OF KENNETH WHIPPLE


I, Kenneth Whipple, certify that:

       1.  I have reviewed this annual report on Form 10-K of CMS Energy
           Corporation;

       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.  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:

                  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;

                  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

                  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

       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 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.



Dated:  March 11, 2004               By:        /s/ Kenneth Whipple
                                        ----------------------------------------
                                                    Kenneth Whipple
                                               Chairman of the Board and
                                               Chief Executive Officer