Exhibit 5


                                               January 18, 2000
Citigroup Inc.
153 East 53rd Street
New York, NY  10043

Ladies and Gentlemen:

      I am General  Counsel-Corporate  Law and Assistant  Secretary of Citigroup
Inc., a Delaware  corporation  (the  "Company").  I have acted as counsel to the
Company  in  connection  with  the  preparation  and  filing  of a  Registration
Statement on Form S-8 (the "Registration Statement") under the Securities Act of
1933, as amended,  for the  registration  of 50,000,000  shares of common stock,
$.01 per  share  par  value  (the  "Shares"),  of the  Company  relating  to the
plans listed on the attached Exhibit A (collectively, the "Plans").

      In connection with the foregoing, I or attorneys under my supervision have
examined  the  minute  books and stock  records  of the  Company,  the  Restated
Certificate  of  Incorporation  and  By-Laws of the  Company,  as  amended,  the
Registration  Statement,  the Plans and resolutions duly adopted by the Board of
Directors  of the Company  relating to the Plans.  In  addition,  I or attorneys
under my supervision have reviewed such other documents and instruments and have
conferred  with  various   officers  and  directors  of  the  Company  and  have
ascertained  or  verified to my  satisfaction  such  additional  facts as I have
deemed  necessary  or  appropriate  for the  purposes of this  opinion.  In such
examination,  I have  assumed the legal  capacity of all  natural  persons,  the
genuineness of all signatures,  the  authenticity of all documents  submitted as
originals,  the conformity to original  documents of all documents  submitted as
certified,  photostatic  or  facsimile  copies,  and  the  authenticity  of  the
originals of such latter documents.

      Based upon the  foregoing I am of the opinion that the Shares to be issued
under the Plans have been duly  authorized  and,  when issued and  delivered  in
accordance with the terms of the Plans,  will be legally issued,  fully paid and
non-assessable.

      My  opinion is limited to  matters  governed  by the  Federal  laws of the
United  States  of  America  and the  General  Corporation  Law of the  state of
Delaware. I am not admitted to the practice of law in the state of Delaware.


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      I hereby  consent  to the  filing of this  opinion  as an  exhibit  to the
Registration  Statement.  In giving this consent,  I do not thereby admit that I
come within the category of persons whose consent is required under Section 7 of
the  Securities  Act of 1933, as amended,  or the Rules and  Regulations  of the
Securities and Exchange Commission thereunder.


                                                 Very truly yours,


                                                 /s/ Stephanie B. Mudick
                                                 -----------------------
                                                 Stephanie B. Mudick
                                                 General Counsel-Corporate Law


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                                   Exhibit A
                                   ---------

Citicorp 1988 Stock Incentive Plan
Citicorp 1997 Stock Incentive Plan
Citicorp Executive Incentive Compensation Plan
Citigroup 2000 Stock Purchase Plan
Travelers Group Capital Accumulation Plan