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                                                                     Exhibit 4.2
                             STOCKHOLDERS AGREEMENT

     THIS AGREEMENT is made as of May 4, 1999 by and among True North
Communications Inc., a Delaware corporation ("True North"), Modem Media . Poppe
                                              ----------
Tyson, Inc., a Delaware corporation ("Modem Media"), and Gerald M. O'Connell and
                                      -----------
Robert C. Allen, II (together, the "Modem Stockholders" and together with True
                                    ------------------
North, collectively referred to as the "Stockholders).
                                        ------------

     WHEREAS, True North, Modem Media, the Modem Stockholders and certain other
parties are party to an Amendment and Competition Agreement dated as of February
3, 1999 (the "Amendment") which amends the Amended and Restated Acquisition
              ---------
Agreement, dated as of December 31, 1996 among such parties (the "Acquisition
                                                                  -----------
Agreement"), and an Agreement and Plan of Merger, dated as of February 3, 1999
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(the "Merger Agreement").

     WHEREAS, True North and the Modem Stockholders are parties to a Letter of
Intent dated May 20, 1998 (the "Letter of Intent").
                                ----------------

     WHEREAS, Modem Media and the Stockholders desire to enter into this
Agreement for the purposes, among others, of establishing the composition of the
Board and making changes to the Acquisition Agreement, the Amendment and the
Letter of Intent.

          NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties to this Agreement hereby agree as
follows:

     1.   The parties hereto agree to the nomination and election to the Board
of Robert H. Beeby, Don Peppers and Joseph Zimmel.

     2.   Until the earlier of (i) the date on which True North and its
affiliates no longer own in the aggregate shares of capital stock of Modem Media
representing at least 35% of the outstanding capital stock of Modem Media and
(ii) December 31, 1999 (the earlier of such date being referred to herein as the
"Expiration Date"), Modem Media shall not, and the Modem Stockholders shall
cause Modem Media to not, without the prior written consent of a majority of the
members of the Board designated by True North, directly or indirectly:

          (a) make any dividends or distributions on, or redemptions or
purchases of, any equity securities of Modem Media;

          (b) issue equity securities in excess of 22.5% of the then-outstanding
equity securities of Modem Media;

          (c) enter into any business other than the business conducted by Modem
Media, or fundamentally change the business of Modem Media, as of the date
hereof;

          (d) establish any subsidiary, partnership, corporation or any other
business enterprise or enter into any joint venture that would be material to
the business or operations of Modem Media;

          (e) sell all or substantially all of the assets of Modem Media;
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          (f) make any acquisitions of or investments in the stock, assets or
              business of any other entity in any form of transaction
              aggregating in excess of $25 million in any one transaction or $50
              million in any 12-month period;

          (g) (i) undertake a liquidation, dissolution, recapitalization or
              reorganization of Modem Media or (ii) make any amendment to Modem
              Media's Bylaws;

          (h) increase or decrease the number of Board members;

          (i) create any new committees of the Board or make any appointments to
              committees of the Board;

          (j) appoint or remove the Chief Executive Officer, Chief Financial
              Officer or President of Modem Media; or

          (k) agree to do any of the foregoing.

     3.   Until the Expiration Date, Modem Media shall not, and the Modem
Stockholders shall cause Modem Media to not, without the prior written consent
of a majority of the independent members of the Board, enter into any contract
or arrangement with any Modem Stockholder or any affiliate thereof.

     4.   Following the Expiration Date until such time as True North and its
affiliates no longer own in the aggregate shares of capital stock of Modem Media
representing at least 10% of the outstanding capital stock of Modem Media, each
Stockholder and Modem Media shall take all actions necessary in order to cause
the election to the Board of at least one director designated by True North.

     5.   Upon the earlier of (i) the date True North and its affiliates no
longer own in the aggregate shares of capital stock of Modem Media representing
at least 35% of the outstanding capital stock of Modem Media and (ii) June 30,
2000, True North agrees that it will, and will cause its affiliates to, convert
the shares of Class B Common Stock of Modem Media then owned by it and its
affiliates into shares of Class A Common Stock of Modem Media.

     6.   The parties hereto agree to enter into a Registration Rights Agreement
substantially in the form attached hereto as Exhibit A.
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     7.   (a) The parties hereto agree that, on the Expiration Date:


                (i)     the Acquisition Agreement will be amended to delete
                        Section 9.9 in its entirety;

                (ii)    the Amendment will be terminated in its entirety; and

                (iii)   the Letter of Intent will be amended to delete Section V
                        thereof in its entirety.
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          (b) After the Expiration Date, to the extent that it is in the mutual
              interest of both parties, Modem Media, FCB Worldwide and Bozell
              Worldwide will cooperate on any projects under such terms and
              conditions as both parties mutually agree.

     8.   Until the date on which True North and its affiliates no longer own in
the aggregate shares of capital stock of Modem Media representing at least 15%
of the then-outstanding capital stock of Modem Media and for the remaining
quarters and final year end results for the year in which True North's ownership
falls below 15%, Modem Media will continue to timely provide True North with all
financial or tax information which True North requests in order to comply with
its public reporting requirements, its tax and other legal requirements.


     9.   This document embodies the complete agreement and understanding among
the parties hereto with respect to the subject matter hereof and supersedes and
preempts any prior understanding, agreements or representations by or among the
parties, written or oral, with respect to such matters.

     10.  Paragraphs 2, 5 and 6 are subject to the ratification by True North's
Board of Directors at its next regularly scheduled meeting.  True North's
management agrees to recommend this document for ratification.


*     *     *     *     *
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     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
date and year first above written.

                              True North Communications Inc.

                                    /s/ Donald S. Seeley
                              By:   ____________________________

                                    Vice Chairman and CFO
                              Its:  ____________________________


                              Modem Media . Poppe Tyson, Inc.

                                    /s/ Gerald M. O'Connell
                              By:   ____________________________

                                    CEO
                              Its:  ____________________________


                              /s/ Gerald M. O'Connell
                              __________________________________
                              Gerald M. O'Connell

                              /s/ Robert C. Allen, II
                              __________________________________
                              Robert C. Allen, II