EXHIBIT 8

January 31, 2005

CMS Energy Corporation
One Energy Plaza
Jackson, MI 49201

Ladies and Gentlemen:

      Reference is made to the prospectus (the "Prospectus"), which constitutes
part of the pre-effective amendment to the registration statement on Form S-3
(Registration No. 333-119255) (the "Registration Statement"), to be filed by CMS
Energy Corporation with the Securities and Exchange Commission on or about the
date hereof pursuant to the Securities Act of 1933, as amended for the
registration for resale of its 3.375% Convertible Senior Notes due 2023, Series
B (the "Notes").

      I am of the opinion that the statements set forth under the caption
"Material United States Federal Income Tax Considerations" in the Prospectus
constitute an accurate description, in general terms, of certain United States
federal income tax considerations that may be relevant to the prospective
holders of the Notes.

      I hereby consent to the filing of this opinion as an exhibit to the
Company's Registration Statement.

                                                 Very truly yours,

                                                 /s/ Jay M. Silverman
                                                     ------------------------
                                                 Jay M. Silverman
                                                 Director of Tax Planning and
                                                 Assistant Tax Counsel