Exhibit 5.2

                         PILLSBURY WINTHROP LLP
                         ONE BATTERY PARK PLAZA
                           NEW YORK, NY 10004




June 6, 2002

Ameren Corporation
1901 Chouteau Avenue
St. Louis, Missouri 63103


Ladies and Gentlemen:

         We have acted as New York counsel to Ameren Corporation, a Missouri
corporation (the "COMPANY"), in connection with the filing by the Company with
the Securities and Exchange Commission (the "COMMISSION") of the Registration
Statement on Form S-3 (the "REGISTRATION STATEMENT") with respect to up to
$1,500,000,000 maximum aggregate offering price of (1) Senior Debt Securities
(the "SENIOR DEBT SECURITIES") to be issued by the Company, (2) Subordinated
Debt Securities (the "SUBORDINATED DEBT SECURITIES") to be issued by the
Company, (3) Trust Preferred Securities to be issued by one or more Delaware
business trusts (the "TRUST PREFERRED SECURITIES"), (4) the Company's guarantees
(the "GUARANTEES") relating to the Trust Preferred Securities, (5) Common Stock,
$.01 par value (the "COMMON STOCK"), to be issued by the Company, (6) contracts
to purchase shares of Common Stock (the "STOCK PURCHASE CONTRACTS") and (7)
units, each comprised of a Stock Purchase Contract and either Senior Debt
Securities or Subordinated Debt Securities, debt obligations of third parties
(including U.S. Treasury securities) or Trust Preferred Securities, in each such
case pledged to secure the holder's obligations to purchase Common Stock under
the Stock Purchase Contract (the "STOCK PURCHASE UNITS" and, together with the
foregoing securities, the "SECURITIES"), in each case, to be issued and sold
from time to time pursuant to Rule 415 under the Securities Act of 1933, as
amended (the "SECURITIES ACT").

         The Senior Debt Securities will be issued pursuant to an Indenture
dated as of December 1, 2001 between the Company and The Bank of New York, as
trustee (the "SENIOR INDENTURE"), the Subordinated Debt Securities will be
issued pursuant to an indenture and the trustee named therein (the "SUBORDINATED
INDENTURE") and the Guarantees will be issued pursuant to one or more guarantee
agreements between the Company and the trustee named therein (each, a "GUARANTEE
AGREEMENT"), in each case as filed or in the respective forms filed or to be
filed as exhibits to the Registration Statement.

         In so acting, we have reviewed originals (or copies certified or
otherwise identified to our satisfaction) of the Registration Statement
(including the exhibits thereto), the Restated Articles of Incorporation and
By-Laws of the Company as in effect



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on the date hereof, corporate and other documents, records and papers and
certificates of public officials. We are members of the Bar of the State of New
York and, for purposes of this opinion, do not hold ourselves out as experts of
the laws of any jurisdiction other than the State of New York.

         On the basis of such review and assuming that (i) the applicable
provisions of the Securities Act, the Trust Indenture Act of 1939, as amended,
and the securities or "blue sky" laws of various states shall have been complied
with, (ii) appropriate resolutions have been adopted by the Board of Directors
of the Company (or a duly appointed committee or representative thereof) and
(iii) the applicable Securities have been issued and sold upon the terms
specified in such resolutions and in any required orders of the Commission or
other applicable regulatory approvals, we are of the opinion that:

         1.       When (i) the supplemental indenture or other instrument under
the Senior Indenture to be entered into, or otherwise executed or adopted, in
connection with the issuance of the Senior Debt Securities, (ii) the
Subordinated Indenture and any supplemental indenture or other instrument
thereunder to be entered into, or otherwise executed or adopted, in connection
with the issuance of the Subordinated Debt Securities or (iii) the Guarantee
Agreements, as applicable, have been duly executed and delivered by the proper
officers of the Company and the trustees named therein, and when the Senior Debt
Securities, the Subordinated Debt Securities and the Guarantees, as the case may
be, have been duly executed, authenticated, delivered and paid for in accordance
with the terms of the Senior Indenture, the Subordinated Indenture and the
Guarantee Agreements, respectively, and on the terms and conditions set forth in
the Registration Statement, the prospectus contained therein and the applicable
supplement thereto, the Senior Debt Securities, the Subordinated Debt Securities
and the Guarantees will be legally issued and will constitute the valid and
binding obligations of the Company, subject to bankruptcy, insolvency,
fraudulent conveyance, reorganization, moratorium and other similar laws
affecting creditors' rights, to general equitable principles (whether considered
in a proceeding in equity or at law) and to an implied covenant of
reasonableness, good faith and fair dealing.

         2.       When (i) the applicable Trust has been duly created under the
Business Trust Act of the State of Delaware, (ii) the Trust Agreement for such
Trust has been duly executed and delivered by the proper officers of the
Company, as sponsor, and the trustees of the Trust named therein and (iii) the
Trust Preferred Securities of such Trust have been executed, delivered and paid
for in accordance with the terms of such Trust Agreement and on the terms and
conditions set forth in the Registration Statement, the



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prospectus contained therein and the applicable supplement thereto, the Trust
Preferred Securities of such Trust will represent valid, fully paid and
nonassessable undivided beneficial interests in the assets of such Trust. We
note, however, that holders of such Trust Preferred Securities may be obligated
to make payments as set forth in the related Trust Agreement.

         3.       When (i) the Stock Purchase Contracts or Stock Purchase Units
have been issued and sold on the terms and conditions set forth in the
Registration Statement, the prospectus contained therein and the applicable
supplement thereto and (ii) the applicable purchase contract agreement and any
related pledge agreement have been duly authorized, executed and delivered by
the parties thereto, the Stock Purchase Contracts or Stock Purchase Units will
be valid and binding obligations of the Company, subject to bankruptcy,
insolvency, fraudulent conveyance, reorganization, moratorium and other similar
laws affecting creditors' rights, to general equitable principles (whether
considered in a proceeding in equity or at law) and to an implied covenant of
reasonableness, good faith and fair dealing.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the references to us under the heading "Legal
Matters" in the related prospectus. In giving this consent, we do not thereby
admit that we are within the category of persons whose consent is required under
Section 7 of the Securities Act or the rules and regulations of the Commission
thereunder.


                                                      Very truly yours,

                                                      Pillsbury Winthrop LLP