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                                                                   EXHIBIT 5(a)




                                                  March 30, 1998





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

Ladies and Gentlemen:

         I am the Assistant General Counsel of CMS Energy Corporation, a
Michigan corporation ("CMS Energy" or 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 not to exceed $200,000,000
of: (i) CMS Energy Common Stock, $.01 par value ("CMS Energy Common Stock");
(ii) CMS Energy Class G Common Stock, no par value ("Class G Common Stock");
(iii) Subordinated Debentures of the Company ("Debentures"); (iv) Trust
Preferred Securities of CMS Energy Trust II (the "Trust"); (v) the guarantee by
the Company of the obligations of the Trust to holders of the Trust Preferred
Securities ("Trust Preferred Securities Guarantee"); (vi) Stock Purchase
Contracts of the Company; and (vii) Stock Purchase Units of the Company. The
offered securities are collectively referred to as the "Securities". The Trust
Preferred Securities Guarantee is to be issued pursuant to a Trust Preferred
Securities Guarantee Agreement (the "Trust Preferred Securities Guarantee
Agreement") to be entered into between the Company and The Bank of New York, as
trustee (the "Guarantee Trustee"). The Debentures are to be issued under an
Indenture to be entered into between the Company and The Bank of New York, as
trustee (the "Indenture Trustee"), and one or more supplemental indentures
thereto (collectively, the "Indenture"). 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



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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 all 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.

         I note that the issuance of the Trust Preferred Securities is governed
by the laws of the State of Delaware. Any matters relating to Delaware law will
be opined upon by Skadden, Arps, Slate, Meagher & Flom.

           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.

           2.   The Company has the corporate power and authority: (i) to
                execute and deliver the Indenture, the Trust Preferred
                Securities Guarantee, and any Stock Purchase Contract or Stock
                Purchase Unit; and (ii) to authorize and sell the Debentures
                pursuant to the Indenture, the CMS Energy Common Stock and the
                Class G Common Stock, and the CMS Energy Common Stock and Class
                G Common Stock.

           3.   The Trust Preferred Securities Guarantee will be a legally 
                issued and binding obligation 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; (ii) the Trust Preferred Securities
                Guarantee shall have been qualified under the Trust Indenture
                Act of 1939, as amended (the "Trust Indenture Act"), and duly
                executed and delivered by the Company and the Guarantee Trustee;
                (iii) the Trust Preferred Securities shall have been legally
                issued; and (iv) the Trust Preferred Securities Guarantee shall
                have been duly executed and delivered as provided in the Trust
                Preferred Securities Guarantee Agreement.

           4.   The Debentures 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; (ii) the Indenture
                shall have been qualified under



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                the Trust Indenture Act and duly executed and delivered by the
                Company and the Indenture Trustee; (iii) an appropriate
                prospectus supplement with respect to the particular Debentures
                then being sold by the Company shall have been filed with the
                Commission pursuant to Rule 424 under the Securities Act; (iv)
                the Company's Board of Directors or duly authorized committee
                thereof shall have duly adopted final resolutions authorizing
                the issuance and sale of the Debentures, as contemplated by the
                Registration Statement and Indenture; (v) the supplemental
                indenture under which the particular Debentures are to be issued
                shall have been duly executed and authenticated as provided in
                the Indenture and such resolutions; and (vi) the Debentures
                shall have been duly delivered to the purchasers thereof against
                payment of the agreed consideration therefor.

           5.   The Stock Purchase Contracts and the Stock Purchase Units, when 
                issued and sold, 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; (ii) an appropriate
                prospectus supplement with respect to the particular Stock
                Purchase Contracts and the particular Stock Purchase Units then
                being sold by the Company shall have been filed with the
                Commission pursuant to Rule 424 under the Securities Act; and
                (iii) the Stock Purchase Contracts under which the CMS Energy
                Common Stock are to be purchased shall have been duly executed
                and delivered as provided in the Stock Purchase Contracts.

           6.   The CMS Energy Common Stock and the Class G Common Stock will 
                be legally issued, fully paid and non-assessable when: (i) the
                Registration Statement, as finally amended, shall have become
                effective under the Securities Act; (ii) 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 Class G Common Stock, the CMS Energy Common Stock, Trust
                Preferred Securities or Debentures to be converted into CMS
                Energy Common Stock or Stock Purchase Contracts pursuant to
                which CMS Energy Common Stock or Class G Common Stock may be
                purchased, as contemplated by the Registration Statement and
                prospectus supplement relating thereto; and (iii) upon delivery,
                purchase or conversion, as the case may be, certificates
                representing the CMS Energy Common Stock or Class G Common Stock
                shall have been duly executed, countersigned and registered and
                duly delivered to the purchasers thereof against payment of the
                agreed consideration therefor.




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           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.

           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 execution and delivery of the Trust
Preferred Securities Guarantee or the sale of the 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 America. I note that the rights, duties
and obligations of the Indenture Trustee under the Indenture are stated to be
governed and construed in accordance with the laws of the State of New York.
However, for purposes of paragraph 4 above, I have assumed that the Indenture,
as to the rights, duties and obligations of the Indenture Trustee, is stated to
be governed by the laws of the State 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 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