SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K

                            Current Report Pursuant
                         to Section 13 or 15(d) of the
                        Securities Exchange Act of 1934


                                January 3, 1997
                 Date of Report (Date earliest event reported)


                               OMNICOM GROUP INC.
             (Exact Name of Registrant as Specified in Its Charter)


                                    NEW YORK
                 (State or Other Jurisdiction of Incorporation)


               1-10551                                  13-1514814
        (Commission File Number)           (I.R.S. Employer Identification No.)


                               437 MADISON AVENUE
                            NEW YORK, NEW YORK 10022
                    (Address of Principal Executive Offices)

                                 (212) 415-3600
              (Registrant's Telephone Number, Including Area Code)


- --------------------------------------------------------------------------------
         (Former Name of Former Address, if Changed Since Last Report)



Item 9. Sales of Equity Securities Pursuant to Regulation S.
        ----------------------------------------------------

     One January 3, 1997,  Omnicom Group Inc. (the "Company") sold  $218,500,000
aggregate  principal  amount of 4 1/4% Convertible  Subordinated  Debentures due
2007  (the  "Debentures").   Morgan  Stanley  &  Co.  Incorporated,  a  Delaware
corporation ("Morgan Stanley"), acted as placement agent and received $4,643,125
in commissions  within the United States,  (i) $208,920,000  principal amount of
Debentures were distributed to "Qualified  Institutional  Buyers" (as defined in
Rule 144A under the Securities Act of 1933, as amended (the  "Securities  Act"))
in compliance with Rule 144A and (ii) $2,330,000  principal amount of Debentures
were  distributed  to  a  limited  number  of  other  institutional  "Accredited
Investors" (as defined in Rule  501(A)(1),  (2), (3) or (7) under the Securities
Act) that,  prior to their purchase of the Debentures,  delivered to the Company
and Morgan Stanley a letter containing certain  representations  and agreements.
Outside the United States in compliance  with  Regulation S under the Securities
Act,  $7,250,000  principal amount of Debentures were  distributed to purchasers
other than "U.S.  Persons" as defined in  Regulation S. The  Debentures  and the
shares of the  Company's  common  stock,  par value $0.50 per share (the "Common
Stock"),  into which the Debentures  may be converted were not registered  under
the Securities Act.

     The Debentures are convertible into Common Stock of the Company at any time
after 90 days  following the latest date of original  issuance  thereof  through
maturity,  unless previously  redeemed or repaid, at a conversion rate of 15.873
shares per bond (initially  representing a conversion price of $63),  subject to
adjustment in certain events.

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                                   SIGNATURES

     Pursuant to the  Securities  Exchange Act of 1934,  the registrant has duly
caused this report to be signed on its behalf by the  undersigned  hereunto duly
authorized.


                                          OMNICOM GROUP INC.                 
                                          
                                          
                                          By:  /s/ Barry J. Wagner
                                               --------------------------
                                               Barry J. Wagner, Secretary

        

Dated: January 17, 1997

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