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                                                                   EXHIBIT 99(a)




                                              August 14, 2002


Securities and Exchange Commission
450 Fifth Street, NW
Washington, DC 20549

         Re: CMS Energy Corporation Form 10-Q for the Period Ended June 30, 2002

To Whom It May Concern:

         As the Chief Executive Officer and the Chief Financial Officer of CMS
Energy Corporation ("CMS Energy" or the "Company"), we are submitting this
letter to the Securities and Exchange Commission to explain the facts and
circumstances due to which the Company's Quarterly Report on Form 10-Q for the
period ended June 30, 2002 (the "Report") is not accompanied by a certification
from us pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906
of the Sarbanes-Oxley Act of 2002.

         As previously disclosed, the Board of Directors of CMS Energy has
formed a special committee to investigate matters surrounding round trip trades
conducted by CMS Energy's subsidiary, CMS Marketing, Services and Trading
Company. The special committee has begun but has not yet completed its work.
(Mr. Whipple is a member of the special committee.)

         Also as previously disclosed, CMS Energy is currently in the process of
restating its 2001 year end balance sheet to adjust for offsetting receivable
and payable amounts of approximately $122 million related to round trip trades,
and restating 2001 revenue and expense of approximately $5 million inadvertently
missed in an earlier reclassification of its 2001 financial statements that
eliminated offsetting revenues and expenses attributed to other such energy
trading transactions (which earlier reclassification is already reflected in CMS
Energy's Annual Report on Form 10-K for the year ended December 31, 2001). This
restatement will also adjust the CMS Energy 2000 year end balance sheet to
eliminate approximately $1 billion of offsetting revenue and expense in that
year. Additional adjustments may be required as a result of the restatement, the
special committee investigation or the re-audit work described below.

         In addition, as has been previously disclosed, by letter dated June 10,
2002, Arthur Andersen LLP informed the Audit Committee of CMS Energy that, in
light of the uncertainty regarding (a) when the special committee will complete
its work, (b) what the results of that work will be, and (c) whether the special
committee's work will have a related impact on previously stated financial
statements, Arthur Andersen's auditor reports related to the consolidated
financial statements of CMS Energy and subsidiaries as of and for the years
ended December 31, 2000 and 2001 cannot be relied upon. While CMS Energy's new
auditor, Ernst & Young LLP, has commenced its audit work, to the extent
necessary to

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support the Company's restatement and filing of a 2001 Form 10-K/A, Ernst &
Young has advised CMS Energy that the re-audit work can only be completed
following receipt of certain assurances regarding the results of the special
committee investigation. In addition, while Ernst & Young has initiated its
review of the Company's financial statements in the Report, it cannot complete
that review until the re-audit work has been completed.  Therefore, the review
required by Section 10-01(d) of Regulation S-X has not been completed and these
financial statements cannot be represented as fully complying with Section 13(a)
of the Securities Exchange Act of 1934, as amended.

         In light of the foregoing circumstances, we have not issued a
certification to accompany the Report pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.


                                       Sincerely yours,

                                       /s/ Kenneth Whipple

                                       Kenneth Whipple
                                       Chairman and Chief Executive Officer

                                       /s/ Alan M. Wright

                                       Alan M. Wright
                                       Chief Financial Officer





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