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                                                               Exhibit 5 & 23(a)

[CMS ENERGY CORPORATION LETTERHEAD]


                                                     MICHAEL D. VAN HEMERT, ESQ.
                                                       ASSISTANT GENERAL COUNSEL



April 7, 1999



CMS Energy Corporation
Fairlane Plaza South, Suite 1100
330 Town Center Drive
Dearborn, MI 48126

Ladies and Gentlemen:

         I am the Assistant General Counsel of CMS Energy Corporation, a
Michigan corporation (the "Company"), and have acted as such in connection with
the Registration Statement on Form S-3 (the "Registration Statement") being
filed by the Company with the Securities and Exchange Commission (the
"Commission") under the Securities Act of 1933, as amended (the "Securities
Act") relating to the registration of $375,000,000 aggregate principal amount of
unsecured senior or subordinated debt securities (the "Debt Securities").
Capitalized terms not otherwise defined herein have the respective meanings
specified in the Registration Statement.

         In rendering this opinion, I have examined and relied upon a copy of
the Registration Statement. I have also examined, or have arranged for the
examination by an attorney or attorneys under my general supervision, originals,
or copies of originals certified to my satisfaction, of such agreements,
documents, certificates and other statements of governmental officials and other
instruments, and have examined such questions of law and have satisfied myself
as to such matters of fact, as I have considered relevant and necessary as a
basis for this opinion. I have assumed the authenticity of the documents
submitted to me as originals, the genuineness of all signatures, the legal
capacity of all natural persons and the conformity with the original documents
of any copies thereof submitted to me for examination.

         Based on the foregoing, it is my opinion that:

         1.       The Company is duly incorporated and validly existing under
                  the laws of the State of Michigan.




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         2.       The Company has the corporate power and authority to sell the
                  Senior Debt Securities pursuant to the Indenture dated
                  September 15, 1992, as supplemented, between the Company and
                  NBD Bank, as trustee (the "Senior Debt Indenture") and the
                  Subordinated Debt Securities pursuant to the Indenture dated
                  June 1, 1997, as supplemented, between the Company and The
                  Bank of New York, as trustee (the "Subordinated Debt
                  Indenture") (the Senior Debt Indenture and Subordinated Debt
                  Indenture, collectively, the "Indentures").

         3.       The Debt Securities will be legally issued and binding
                  obligations of the Company (except to the extent
                  enforceability may be limited by applicable bankruptcy,
                  insolvency, reorganization, moratorium, fraudulent transfer or
                  other similar laws affecting the enforcement of creditors'
                  rights generally and by the effect of general principles of
                  equity, regardless of whether enforceability is considered in
                  a proceeding in equity or at law) when:

                  (i)      the Registration Statement, as finally amended
                           (including any necessary post-effective amendments),
                           shall have become effective under the Securities Act
                           and the Indentures (including any necessary
                           supplemental indentures) shall have been qualified
                           under the Trust Indenture Act of 1939, as amended,
                           and duly executed and delivered by the Company and
                           the Trusteess;

                  (ii)     an appropriate Prospectus Supplement with respect to
                           the particular Debt Securities then being sold by the
                           Company shall have been filed with the Commission
                           pursuant to Rule 424 under the Securities Act;

                  (iii)    the Company's Board of Directors or a duly authorized
                           committee thereof shall have duly adopted final
                           resolutions authorizing the issuance and sale of the
                           Company as contemplated by the Registration Statement
                           and the particular Indenture; and

                  (iv)     the supplemental Indenture under which the particular
                           Debt Securities are to be issued has been duly
                           authorized, executed and delivered, and the
                           particular Debt Securities then being sold by the
                           Company shall have been duly executed and
                           authenticated as provided in the particular Indenture
                           and such resolutions, and shall have been duly
                           delivered to the purchasers thereof against payment
                           of the agreed consideration therefor.

         For purposes of this opinion, I have assumed that there will be no
changes in the laws currently applicable to the Company and that such laws will
be the only laws applicable to the Company.



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         I do not find it necessary for the purposes of this opinion to cover,
and accordingly I express no opinion as to, the application of the securities or
blue sky laws of the various states to the sale of the Debt Securities.

         I am a member of the bar of the State of Michigan and I express no
opinion as to the laws of any jurisdiction other than the State of Michigan and
the federal law of the United States of Michigan.

         I hereby consent to the filing of this opinion as an exhibit to the
Company's Registration Statement on Form S-3 relating to the Debt Securities and
to all references to me included in or made a part of the Registration
Statement.

Very truly yours,


/s/ Michael D. Van Hemert

Michael D. Van Hemert