EXHIBIT 5.01

                                        June 20, 2006

Citigroup Inc.
399 Park Avenue
New York, New York 10043

Ladies and Gentlemen:

     I am the General Counsel, Finance and Capital Markets of Citigroup Inc., a
Delaware corporation (the "Company"). I refer to the filing by the Company with
the Securities and Exchange Commission (the "Commission") of a Registration
Statement on Form S-3 (the "Registration Statement") relating to junior
subordinated debt securities (the "Junior Subordinated Debt Securities") issued
in connection with the offering by certain affiliated business trusts of the
Company of enhanced capital securities, certain payments in respect of which
will be guaranteed by the Company (the "Guarantees"). The Junior Subordinated
Debt Securities being registered under the Registration Statement will be
offered on a continued or delayed basis pursuant to the provisions of Rule 415
under the Securities Act of 1933, as amended (the "Act").

     Unless otherwise provided in any prospectus forming a part of the
Registration Statement, the Junior Subordinated Debt Securities will be issued
under an Indenture to be entered into (the "Junior Indenture"), between the
Company and JPMorgan Chase Bank, N.A. (the "Junior Trustee"), as Trustee. The
form of Junior Indenture is attached as an exhibit to the Registration
Statement.

     I, or attorneys under my supervision, have examined and are familiar with
originals, or copies certified or otherwise identified to my satisfaction, of
such corporate records of the Company, certificates or documents as I have
deemed appropriate as a basis for the opinions expressed below. In such
examination, I (or such persons) have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to me (or such persons) as originals, the conformity to original
documents of all documents submitted to me (or such persons) as certified or
photostatic copies and the authenticity of the originals of such copies.

     Based upon and subject to the foregoing and assuming that (i) a Prospectus
and/or term sheet will have been prepared and filed with the Commission
describing the Junior Subordinated Debt Securities offered thereby and will
comply with all applicable laws; (ii) all Junior Subordinated Debt Securities
will be issued and sold in compliance with applicable federal and state laws and
in the manner stated in the Registration Statement and the Prospectus Supplement
and/or term sheet; (iii) the Junior Indenture and a definitive purchase,
underwriting or similar agreement and any other necessary agreement with respect
to the Junior Subordinated Debt Securities offered or issued will have been duly
authorized and validly executed and delivered by the parties thereto; (iv) the
Junior Subordinated Debt Securities will be sold and delivered at the price and
in accordance with the terms of such agreement and as set forth in the
Registration Statement and the Prospectus or term



sheet(s) referred to therein; and (v) the Company will authorize the offering
and issuance of the Junior Subordinated Debt Securities and the terms and
conditions thereof and will take any other appropriate additional corporate
action, I am of the opinion that:

     1. The Company is a duly incorporated and existing corporation under the
laws of the State of Delaware.

     2. Assuming the due authorization, execution, and delivery of the Junior
Indenture by the Junior Trustee, and due execution, authentication and delivery
of the Junior Subordinated Debt Securities in accordance with the terms of the
Junior Indenture, when such Junior Subordinated Debt Securities have been issued
and sold in the manner contemplated by the Registration Statement, such Junior
Subordinated Debt Securities will be legal, valid and binding obligations of the
Company and will be entitled to the benefits of the Junior Indenture.

     Insofar as my opinion relates to the validity, binding effect or
enforceability of any agreement or obligation of the Company, it is subject to
applicable bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or other similar laws affecting creditors' rights generally from time
to time in effect and subject to general principles of equity, regardless of
whether such is considered in a proceeding in equity or at law.

     My opinion is limited to matters governed by the Federal laws of the United
States of America, the laws of the State of New York and the General Corporation
Law of the State of Delaware (including the applicable provisions of the
Delaware Constitution and the reported judicial decisions interpreting the
General Corporation Law of the State of Delaware and such applicable provisions
of the Delaware Constitution). I am not admitted to the practice of law in the
State of Delaware.

     I consent to the use of this opinion in the Registration Statement and to
the reference to my name in the Prospectus constituting a part of such
Registration Statement under the heading "Legal Matters." In giving such
consent, I do not thereby admit that I come within the category of persons whose
consent is required under Section 7 of the Act, or the rules and regulations of
the Securities and Exchange Commission thereunder.

                                        Very truly yours,


                                        /s/ Michael S. Zuckert
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