EXHIBIT 3.1

                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                              OMNICOM GROUP INC.
              (under Section 805 of the Business Corporation Law)

FIRST:  The name of the  corporation is Omnicom Group Inc. ("the  Corporation").
The name under which the Corporation was formed is Maxwell Dane, Inc.

SECOND:  The  Certificate of  Incorporation  of the Corporation was filed by the
Department  of  State  on  November  17,  1944  and a  Restated  Certificate  of
Incorporation was filed on May 31, 1988.

THIRD: The Certificate of Incorporation of the Corporation is amended to effect
the following amendment authorized by the Business Corporation Law:

      Article  FOURTH of the  Certificate of  Incorporation  is being amended to
change  the  300,000,000  shares of common  stock at $.50 par value per share to
1,000,000,000  shares of common stock at $.15 par value per share. To accomplish
the foregoing,  the 187,086,161  issued shares of common stock at $.50 par value
per share will change into 187,086,161 issued shares of common stock at $.15 par
value per share at a rate of one for one, and the remaining 112,913,839 unissued
shares of common stock at $.50 par value per share will change into  812,913,839
unissued  shares of common stock at $.15 par value per share at a rate of 7.1994
to one.

FOURTH: To accomplish the foregoing amendment, Article FOURTH of the Certificate
of Incorporation is hereby amended to read as follows:

      "FOURTH:  The total number of shares of stock which the  Corporation  will
have authority to issue is 1,007,500,000 shares. Of these,  1,000,000,000 shares
are classified as Common Stock,  par value $.15 per share,  and 7,500,000 shares
are classified as Preferred  Stock,  par value $1.00 per share. At the effective
time of the  amendment  to this Article  decreasing  the par value of the Common
Stock to $.15 per  share,  and  without  any  further  action on the part of the
Corporation or its shareholders,  each share of Common Stock with a par value of
$.50 then issued and outstanding  shall be changed and reclassified into a fully
paid and nonassessable share of Common Stock with a par value of $.15.

      The Board of Directors is  authorized  to divide the  7,500,000  shares of
Preferred  Stock from time to time into one or more series,  and to determine or
change by resolution  for each series its  designation,  the number of shares of
the series and the  powers,  preferences  and  rights,  and the  qualifications,
limitations  or  restrictions  of the shares of the series.  The  resolution  or
resolutions of the Board



of Directors  providing for the division of Preferred Stock into series within a
class may include the following provisions:

      (1) The  distinctive  designation of each series and the maximum number of
shares of each series which may be issued, which number may be increased (except
where  otherwise  provided by the Board of  Directors in creating the series) or
decreased  (but not below the number of shares of the series  then  outstanding)
from time to time by action of the Board of Directors;

      (2) Whether the holders of the shares of each series are  entitled to vote
and, if so, the matters on which they are entitled to vote,  the number of votes
to which the holder of each share is  entitled,  and  whether  the shares of the
series are to be voted separately or together with shares of other series;

      (3) The  dividends  to which  holders  of  shares of each  series  will be
entitled; any restrictions,  conditions or limitations upon the payment of those
dividends; whether the dividends will be cumulative and, if cumulative, the date
or dates from which the dividends will be cumulative;

      (4) Whether the shares of one or more series will be subject to redemption
and, if so, whether  redemption will be mandatory or optional,  and if optional,
at whose option,  the manner of selecting shares for redemption,  the redemption
price and the manner of redemption;

      (5) The amount payable on shares of each series if there is a liquidation,
dissolution or winding up of the Corporation, which amount may vary at different
dates and depending upon whether the  liquidation,  dissolution or winding up is
voluntary or involuntary;

      (6) The  obligation,  if any, of the  Corporation  to maintain a purchase,
retirement or sinking fund for shares of each series;

      (7) Whether the shares of one or more series will be convertible  into, or
exchangeable  for,  any other types of  securities,  either at the option of the
holder  or of the  Corporation  and,  if so,  the  terms of the  conversions  or
exchanges;

      (8) Any other provisions regarding the powers, preferences and rights, and
the  qualifications,  limitations or restrictions,  of each series which are not
inconsistent with applicable law.

      All  shares of a series of  Preferred  Stock will be  identical  with each
other in all respects,  except that shares of any one series issued at different
times may  differ as to the dates  from  which  dividends  on those  shares,  if
cumulative, shall cumulate."


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FIFTH: The amendment to the Certificate of  Incorporation  was authorized by the
vote of the majority of the holders of all  outstanding  shares entitled to vote
on an amendment to the  Certificate of  Incorporation.  Said  authorization  was
subsequent to the affirmative vote of the Board of Directors.

IN WITNESS WHEREOF, this Certificate has been signed this 17th day of May, 2000,
and the  signatures of the  undersigned  shall  constitute the  affirmation  and
acknowledgement  of the  undersigned,  under  penalties  of  perjury,  that this
Certificate is the act and deed of the  undersigned and that the facts stated in
this Certificate are true.

Omnicom Group, Inc.

By: /s/ John Wren                           By: /s/ Barry J. Wagner
    ------------------------------              ------------------------------
    John Wren, President                        Barry J. Wagner, Secretary


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