<PAGE>

[LOGO OF TRUE NORTH COMMUNICATIONS, INC.]

101 EAST ERIE STREET, CHICAGO, ILLINOIS 60611-2897, USA   PHONE 312 425 6500
FAX 312 425 6350

DAVID A. BELL
CHAIRMAN AND CHIEF EXECUTIVE OFFICER



                                 April 5, 2000

Via Overnight Mail

Mr. Donald L. Seeley
1862 N. Dayton
Chicago, IL 60614

     Re:  Continued Employment
          --------------------

Dear Don:

     The purpose of this letter is to set forth the terms and conditions of
your continued employment with True North Communications Inc. (the "Company")
and to confirm certain other aspects relating to your new position with the
Company.

1.   Employment Period.  You have resigned as Executive Vice President and Chief
     Financial Officer effective March 15, 2000.  Beginning March 16, 2000, you
     will serve as an employee of the Company for so long as that arrangement is
     mutually acceptable to both you and the Company (the "Employment Period").
     As of the date hereof, both parties contemplate that the Employment Period
     will last for at least one year.

2.   Employment Duties and Responsibilities.  During the Employment Period, you
     will serve as Advisor to the Chief Executive Officer of the Company and
     will perform employment services no less than five days each calendar
     quarter.  You will report directly to the Chief Executive Officer and will
     perform such services, consistent with your status as a former Executive
     Vice President and Chief Financial Officer, as are reasonably requested by
     the Chief Executive Officer or the Board of Directors of the Company from
     time to time.  During the Employment Period, you will also agree to
     continue to serve as one of the Company's employee representatives on the
     Company's Board of Directors and the Board of Directors of Modem Media .
     Poppe Tyson, Inc. (assuming your continued nomination to serve as such and
     your continued election by stockholders).
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Mr. Donald L. Seeley
April 5, 2000
Page 2


3.   Compensation and Benefits.  Your compensation during the Employment Period
     shall consist of the following (subject to applicable tax withholding
     obligations):

     .  Base salary at the rate of $120,000 per year, payable in accordance with
        the payroll procedures for salaried employees.

     .  Quarterly bonuses in amounts to be determined by the Chief Executive
        Officer in his sole discretion for special contributions to the Company,
        including time spent preparing for and attending special Company and
        Modem Media . Poppe Tyson, Inc. Board of Directors' and committee
        meetings as an employee representative of the Company.

     .  During the Employment Period, you will remain eligible to make pre-tax
        contributions and receive corresponding Company matching contributions
        under the True North Retirement Plan. You will not be eligible for any
        incentive compensation, fringe benefits or other employee benefits
        during the Employment Period.

     .  During the Employment Period, the Company shall reimburse you for all
        reasonable travel and other business expenses incurred by you in the
        performance of your duties hereunder in accordance with the Company's
        standard business expense reimbursement policies and procedures.

4.   Treatment of Other Employee Benefits.  Based on the transition of your
     responsibilities with the Company, the following shall apply:

     .  True North Retirement Plan.  You will not be eligible to receive a
        distribution from this Plan until the end of the Employment Period
        (subject to certain early withdrawal rights that would apply once you
        reach age 59-1/2).

     .  True North Executive Deferred Compensation Plan.  Your participation in
        this Plan will cease as of March 15, 2000, because your adjusted
        compensation will not meet the applicable thresholds for participation
        in the Plan. Distribution of your benefits from this Plan (and the
        corresponding "Integration" Plans) will be made in accordance with your
        earlier election(s).

     .  True North Stock Options.  In accordance with and subject to the terms
        of the applicable stock option agreements, you will continue to vest in
        your outstanding unvested stock options during the Employment Period. To
        recognize your past service to the Company, the Compensation Committee
        granted you a stock option for 50,000 shares in March 2000. In
        accordance with the terms and conditions of the underlying stock option
        agreement (which is attached hereto as Exhibit A), this stock
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Mr. Donald L. Seeley
April 5, 2000
Page 3


        option is fully vested and exercisable immediately, and shall remain
        exercisable until March 1, 2005.

     .  Restricted Stock.  In accordance with and subject to the terms of the
        applicable restricted stock agreement, you will continue to vest in your
        outstanding unvested restricted stock during the Employment Period.

     .  Earnings Performance Units.  All of your earnings performance units
        shall be canceled as of March 15, 2000.

     .  Executive Life Insurance.  You will receive information directly from
        Paragon regarding your option to convert this coverage to an individual
        policy.

5.   Employment Relationship; Termination.  During the Employment Period, you
     will continue to be an employee at will, and either you or the Company may
     terminate the relationship at any time with or without cause, upon 30 days'
     advance written notice.  Neither party has an obligation to base a decision
     to terminate the employment relationship on any reason other than the
     intent not to continue the relationship.  If you remain a member of the
     Board of Directors of the Company or the Board of Directors of Modem Media.
     Poppe Tyson, Inc. after the end of the Employment Period, then you will be
     compensated for such Board membership in accordance with the Company's
     standard outside director compensation programs.

6.   Resignation.  By signing the form attached as Exhibit B, you have resigned
     from the various officer and board of director positions listed, effective
     March 15, 2000.

7.   Entire Agreement.  This letter agreement constitutes the entire agreement
     between you and the Company and supersedes all prior agreements, including
     the Employment Agreement dated May 1, 1998; provided that you remain
     subject to the provisions of Sections 7, 8 and 9 of that Employment
     Agreement, and the restrictions set forth in Section 7(a)(i)-(iii) of that
     Employment Agreement shall apply during the Employment Period and during
     your membership on the Board of Directors of the Company.

8.   Confidentiality.  The economic terms and conditions set forth in this
     letter are to be kept strictly confidential; provided that you may disclose
     these terms to your legal counsel, your personal tax and financial advisors
     and to members of your immediate family.
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Mr. Donald L. Seeley
April 5, 2000
Page 4


     Please sign below to indicate that you have reviewed this letter and are in
agreement with its terms.

                                    Sincerely,

                                    /s/ David A. Bell

                                    David A. Bell

Agreed and Accepted:


/s/ Donald L. Seeley
________________________
Donald L. Seeley


Dated: 4/5/00


cc:  Kevin Smith
     Terry Peigh
     Sue Bettman
     Dan Barker
     Paul Sollitto
     Mike Oettinger
     Tom Roberts
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                                                                       EXHIBIT A
                                                                       ---------

                   [LOGO OF TRUE NORTH COMMUNICATIONS, INC.]


                        TRUE NORTH COMMUNICATIONS INC.
                            STOCK OPTION AGREEMENT

          THIS AGREEMENT is entered into as of the 1st day of March 2000 (the
"Date of Grant"), by and between TRUE NORTH COMMUNICATIONS INC. (the
"Corporation"), a Delaware corporation, and Donald L. Seeley (the "Optionee").

                                 WITNESSETH:
                                 ----------

          WHEREAS, the Optionee is currently providing key services to the
Corporation or one of its subsidiary corporations;

          WHEREAS, in recognition of the past services of the Optionee to the
Corporation and in contemplation of the key services to be performed by the
Optionee in the future, the Corporation considers it desirable and in its best
interest that the Optionee be given an inducement to acquire a proprietary
interest in the Corporation and an added incentive to advance the interests of
the Corporation in the form of an option to purchase common stock of the
Corporation ("Common Stock"); and

          WHEREAS, the Compensation Committee of the Corporation, at a duly
constituted meeting held on the Date of Grant pursuant to the provisions of the
True North Communications Inc. Stock Option Plan (the "Plan"), granted the
Optionee the option described herein.

          NOW, THEREFORE, THE PARTIES AGREE AS FOLLOWS:

          1.  This Agreement recites all the terms and conditions of the option
granted to the Optionee by the Corporation on the Date of Grant; provided,
however, that this Agreement is subject to the provisions of the Plan and shall
be interpreted in accordance therewith.  The option evidenced by this Agreement
(the "Option") is intended to be a "non-qualified stock option" and shall not be
treated as an incentive stock option within the meaning of Section 422 of the
Internal Revenue Code of 1986, as amended.

          2.  The Corporation grants to the Optionee the Option to purchase from
the Corporation 50,000 shares of Common Stock at the price of $37.00 per share,
being at least 100% of the fair market value of the stock on the Date of Grant,
in the manner and subject to the provisions hereinafter provided.

          3.  The Option herein granted shall terminate in all respects on, and
no exercise as to any shares covered by said Option shall be honored on or after
March 1, 2005 (the "Expiration Date").  Notwithstanding the foregoing, if at any
time during the term of the Option, the Optionee materially breaches any of his
obligations under Section 7 or 8 of the Employment Agreement between the
Optionee and the Corporation dated May 1, 1998, the Option shall expire
<PAGE>

and become null and void on the date of such breach.

          4.  The Option granted hereby is 100% vested and exercisable by the
Optionee at any time from the Date of Grant through the Expiration Date.  During
the lifetime of the Optionee, the Option shall be exercisable only by the
Optionee.  If at any time during the term of the Option, the Optionee shall die,
the Option shall be exercisable by the Optionee's designated beneficiary or by
his estate, as applicable, from the date of death through the Expiration Date.

          5.  (a)  The Option granted hereby shall be exercisable by the
delivery by the Optionee (or the Optionee's personal representative, as the case
may be) of a properly completed stock option exercise form to the Corporation or
its designee, attention:  Assistant Treasurer, at its office at 101 East Erie
Street, Chicago, IL 60611-2897, stating the number of shares with respect to
which the Option is being exercised and specifying a date (unless payment is to
be made in the manner provided for in subparagraph (b) of this Paragraph) on
which the shares will be taken and payment made therefor.  On or about the date
specified in the notice of election, the Corporation shall deliver, or cause to
be delivered, to the Optionee or the Optionee's designee stock certificates or
electronic shares for the number of shares with respect to which the Option is
being exercised, and for which full payment, including payment with respect to
any tax withholding obligations, has been received.

          (b) At the request of the Optionee, and if approved by the Corporation
as provided in the Plan, payment for shares as to which the Option is being
exercised and/or payment of any federal, state, local or other tax withholding
obligation may be made by transfer to the Corporation of shares of the
Corporation already owned by the Optionee, or any combination of such shares and
cash, having a fair market value determined at the close of business on the date
of Option exercise equal to, but not exceeding, the Option price and/or the tax
withholding obligation, as the case may be.  In the alternative and also at the
request of the Optionee and subject to the approval of the Corporation, the
Corporation may satisfy any such tax withholding obligation by withholding from
the number of shares to be delivered to the Optionee that number of shares
(based on the then fair market value of the shares) equal to the amount of such
tax to be withheld.  Any such request shall be made in writing, and the
Corporation shall notify the Optionee within 14 days after receipt of the
disposition of such request.  The denial of such request will not prevent the
Optionee from exercising the Option for cash or from paying the tax withholding
obligation in cash, as applicable.  If such request is approved, the Corporation
shall within five days thereafter deliver, or cause to be delivered, to the
Optionee stock certificates for the number of shares as to which the Option is
being exercised, against payment therefore in whole or in part in shares of the
Corporation.

          (c) Delivery of the shares may be made at the office of the
Corporation or at the office of a transfer agent appointed for the transfer of
shares of the Corporation, as the Corporation shall determine.  Shares shall be
registered in the name of the Optionee or the Optionee's personal
representative, as the case may be.  Neither the Optionee nor the Optionee's
personal representative shall have any of the rights of a shareholder until the
shares are issued as herein provided.  In the event of any failure to take and
pay for the number of shares specified in the notice of election on the date
stated therein, the Option shall become inoperative as to such number of shares,
but shall continue with respect to any remaining shares subject to the Option as
to which exercise has not yet been made.  Anything herein to the contrary
notwithstanding, if a law or any regulation of the Securities and Exchange
Commission or of any other body having

                                       2
<PAGE>

jurisdiction shall require the Corporation or the Optionee to take any action in
connection with the shares specified in a notice of election before such shares
can be delivered to such Optionee, then the date stated therein for the delivery
of the shares shall be postponed until the fifth business day next following the
completion of such action.

          6.  The Option granted hereby shall not be assigned, pledged or
hypothecated in any way, shall not be subject to execution and shall not be
transferable by the Optionee other than by will, the laws of descent and
distribution or to a designated beneficiary in the event of the Optionee's
death.  Any attempt at assignment, transfer, pledge, hypothecation or other
disposition of the Option granted hereby contrary to the provisions thereof, and
the levy of any attachment or similar proceeding upon the Option shall be null
and void.

          7.  If any change is made in the stock subject to the Option granted
hereby by reason of stock dividends or split-ups, appropriate actions shall be
taken by the Board of Directors of the Corporation as to the number of shares
and price per share subject to the Option in order to prevent dilution.

          8.  Upon the complete liquidation of the Corporation, any unexercised
portion of the Option shall be deemed canceled.

          9.  The Option, this Agreement and all determinations made and actions
taken pursuant thereto, to the extent otherwise not governed by the Internal
Revenue Code of 1986, as amended, the laws of the United States or the laws of
the State of Delaware, shall be governed by and construed in accordance with the
laws of the State of Illinois.

          10.  This Agreement shall be binding upon and inure to the benefit of
any successor or successors of the Corporation and any person or persons who
shall, upon the death of the Optionee, acquire any rights hereunder.

          11.  The Compensation Committee of the Corporation may, from time to
time, amend the terms and conditions of this Option, but only with the written
consent of the Optionee or the Optionee's legal representative.

          12.  The Option shall be null and void unless the Optionee shall
accept this Agreement by executing it in the space provided below and returning
this original executed Agreement to the Corporation.

          IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above mentioned.

OPTIONEE                             TRUE NORTH COMMUNICATIONS INC.



_______________________________      By: ___________________________________
Donald L. Seeley                     Name: _________________________________
                                     Title: ________________________________

                                       3
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                                                                       Exhibit B



                                March 15, 2000


     I, Donald L. Seeley, do hereby resign from each of the positions I hold
with respect to each of the entities listed below, all such resignations to be
effective as of the date hereof.


                                           /s/ Donald L. Seeley
                                           -----------------------------
                                           Donald L. Seeley

FCB Worldwide L.L.C.                       Manager
FCB Worldwide, Inc.                        Director
Market Growth Resources, Inc.              Director and Executive Vice President
True North Communications Inc.             Vice Chairman, Executive Vice
                                           President and Chief Financial Officer
True North Foundation                      Director
True North Holdings (Asia Pacific), Inc.   Executive Vice President
True North Holdings (United Kingdom)       Director
Limited
True North Management Executive            Member
Committee
True North Outside Director Stock Option   Member
Plan Administrative Committee