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                                                                   Exhibit 10(i)

                           NORTHERN TRUST CORPORATION

                             ANNUAL PERFORMANCE PLAN

                                      2003

I.   Purpose of Plan

     The purpose of the Annual Performance Plan (the "Plan") is to promote the
     achievement of superior financial and operating performance of the Northern
     Trust Corporation (the "Corporation") and its subsidiaries (collectively,
     the Corporation and its subsidiaries, "Northern Trust"), and further the
     objective of delivering unrivaled service quality to its clients and
     partners through the awarding of cash incentive payments to selected
     officers.

II.  Plan Year/Effective Date/Termination

     The Plan Year for this Plan will be the calendar year from January 1, 2003
     to December 31, 2003. The Plan is effective as of January 1, 2003 and
     automatically terminates on December 31, 2003.

III. Eligibility and Participation

     Eligibility to participate in the Plan is restricted to officers with the
     title of Vice President and above who are not eligible for participation in
     a Specialized Incentive Plan. Plan participation is reviewed each year, and
     participation in one year does not automatically indicate participation in
     subsequent Plan years. Participation in the Plan is based upon
     recommendation from the respective Business Unit Head.

IV.  Award Funding

     At the beginning of the Plan year, the Compensation and Benefits Committee
     of the Board of Directors of the Corporation will determine a Corporate
     Earnings Target and profit plan funding for awards under the Annual
     Performance Plan. The allocation of the plan award funding to each
     respective Business Unit will be based on the salaries of the eligible
     officers within the Business Unit. Within each Business Unit, one-half of
     the available funding for awards under the Plan will be based on the
     Northern Trust's financial achievement versus the Corporate Earnings
     Target. The other half of the award funding is based on the financial
     achievement of the Business Unit versus the Business Unit's earnings
     target. For staff support units, the available funding for awards will be
     based entirely on the financial achievement of Northern Trust versus the
     Corporate Earnings Target. Management reserves the right to either increase
     or decrease the original funding amount. A guideline showing potential
     adjustments to award funding based on Corporate and Business Unit
     performance is provided in Attachment I.

V.   Individual Award Determination

     Individual participant awards will be discretionary. They will be
     determined by Business Unit Management based on an assessment of individual
     performance relative to performance expectations, contribution to financial
     and operating goals, competitive level of total compensation, and available
     award pool funding.


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VI.   Payment of Awards

      Awards will be paid in cash as soon as practicable following the
      completion of the Plan year. Awards payable because of a Change in Control
      of the Corporation pursuant to Paragraph IX shall be paid in cash as soon
      as practicable following such Change in Control.

VII.  Administration

      The Plan shall be administered by the Management Committee of the
      Corporation (the "Committee"). Subject to the provisions of the Plan, the
      Committee shall be authorized to interpret the Plan, to establish, amend,
      and rescind any rules and regulations relating to the Plan, and to make
      all other determinations necessary or advisable for the administration of
      the Plan. The determinations of the Committee in the effective
      administration of the Plan, as described herein, shall be final and
      conclusive.

      The Compensation and Benefits Committee of the Board of Directors of the
      Corporation, by written resolution, may amend, suspend, or terminate any
      or all provisions of the Plan at any time.

VIII. Other Provisions

      The following miscellaneous provisions are applicable to the Plan:

(a)   None of the provisions of this Plan will override general Corporate
      Policy.

(b)   Termination of employment by a participant during the Plan Year, either
      voluntary or involuntary with cause, and for reasons other than death,
      disability, or retirement shall result in immediate exclusion from the
      Plan. For purposes of this Plan, "Retirement" means the termination of the
      participant's employment with Northern Trust by reason of participant
      having attained the age of 65 years or older or after the participant has
      qualified for an Early Retirement Pension under The Northern Trust Company
      Pension Plan. For purposes of this Plan, "Disability" means a participant
      has been receiving short-term and long-term disability benefits under
      Northern Trust's Managed Disability Program for 12 consecutive months.

(c)   Except in the event of the death of a participant, the rights and
      interests of a participant under the Plan shall not be assigned,
      encumbered, or transferred.

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(d)   No employee or other person shall have any claim or right to be granted an
      award under the Plan. Neither the Plan, nor any action taken thereunder,
      shall be construed as giving any employee or other person any right to be
      retained in the employ of the Corporation for any length of time.
      Participants in the Plan will remain at-will employees for all purposes.

(e)   The Corporation shall have the right to deduct from all payments made
      under the Plan any taxes required by law to be withheld with respect to
      such payment.

(f)   All questions pertaining to the validity, construction and administration
      of the Plan and any award hereunder shall be determined in conformity with
      the laws of the State of Illinois.

(g)   Each participant shall designate a beneficiary (the "Designated
      Beneficiary") to receive the award, if any, allocated to a participant, in
      the event of such participant's death. If no Designated Beneficiary
      survives the participant, it shall be the surviving spouse of the
      participant or, if there is no surviving spouse, it shall be the
      participant's estate.

IX.   Change in Control

      Notwithstanding any other terms contained herein, in the event of a Change
      in Control of the Corporation, funding for awards under the Plan shall be
      determined as if the Corporation and Business Units had achieved the
      respective earnings targets, as described in Section IV. Discretionary
      awards shall be paid to participants as soon as practicable. For purposes
      of this paragraph, a "Change in Control" shall be deemed to have occurred
      if

          (1) any Person is or becomes the Beneficial Owner, directly or
          indirectly, of securities of the Corporation (not including in the
          securities beneficially owned by such Person any securities acquired
          directly from the Corporation or its affiliates) representing 20% or
          more of the combined voting power of the Corporation's then
          outstanding securities, excluding any Person who becomes such a
          Beneficial Owner in connection with a transaction described in clause
          (i) of paragraph (3) below; or

          (2) the election to the Board of Directors of the Corporation, without
          the recommendation or approval of two thirds of the incumbent Board of
          Directors of the Corporation, of the lesser of: (A) three directors;
          or (B) directors constituting a majority of the number of directors of
          the Corporation then in office, provided, however, that directors
          whose initial assumption of office is in connection with an actual or
          threatened election contest, including but not limited to a consent
          solicitation, relating to the election of directors of the Corporation
          will not be considered as incumbent members of the Board of Directors
          of the Corporation for purposes of this section; or

          (3) there is consummated a merger or consolidation of the Corporation
          or any direct or indirect subsidiary of the Corporation with any other
          company, other than (i) a merger or consolidation which would result
          in the voting securities of the Corporation outstanding immediately
          prior to such merger or consolidation continuing to represent (either
          by remaining outstanding or by being converted into voting securities
          of the surviving entity or any parent thereof), at least 60% of the
          combined voting power of the securities of the Corporation or such
          surviving entity or any parent thereof outstanding immediately after
          such merger or consolidation, or (ii) a merger or consolidation
          effected to implement a recapi-

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          talization of the Corporation (or similar transaction) in which no
          Person is or becomes the Beneficial Owner, directly or indirectly, of
          securities of the Corporation (not including in the securities
          Beneficially Owned by such Person any securities acquired directly
          from the Corporation or its Affiliates) representing 20% or more of
          the combined voting power of the Corporation's then outstanding
          securities; or

          (4) the stockholders of the Corporation approve a plan of complete
          liquidation or dissolution of the Corporation or there is consummated
          an agreement for the sale or disposition by the Corporation of all or
          substantially all of the Corporation's assets, other than a sale or
          disposition by the Corporation of all or substantially all of the
          Corporation's assets to an entity, at least 60% of the combined voting
          power of the voting securities of which are owned by stockholders of
          the Corporation in substantially the same proportions as their
          ownership of the Corporation immediately prior to such sale.

Notwithstanding the foregoing, a "Change in Control" shall not be deemed to have
occurred by virtue of the consummation of any transaction or series of
integrated transactions immediately following which the record holders of the
common stock of the Corporation immediately prior to such transaction or series
of transactions continue to have substantially the same proportionate ownership
in an entity which owns all or substantially all of the assets of the
Corporation immediately following such transaction or series of transactions.

For purposes of the foregoing, the following definitions shall apply:

     "Affiliate" shall have the meaning set forth in Rule 12b-2 under Section 12
     of the Exchange Act; "Beneficial Owner" shall have the meaning set forth in
     Rule 13d-3 under the Exchange Act, except that a Person shall not be deemed
     to be the Beneficial Owner of any securities with respect to which such
     Person has properly filed a Form 13-G; "Exchange Act" shall mean the
     Securities Exchange Act of 1934, as amended from time to time; and "Person"
     shall have the meaning given in Section 3(a)(9) of the Exchange Act, as
     modified and used in Sections 13(d) and 14(d) thereof, except that such
     term shall not include (i) the Corporation or any of its Affiliates, (ii) a
     trustee or other fiduciary holding securities under an employee benefits
     plan of the Corporation or any of its subsidiaries, (iii) an underwriter
     temporarily holding securities pursuant to an offering of such securities
     or (iv) a corporation owned, directly or indirectly, by the stockholders of
     the Corporation in substantially the same proportions as their ownership of
     stock of the Corporation.

Notwithstanding anything in this Plan to the contrary, in the event of a
Potential Change in Control and for a period of six (6) months following the
Potential Change in Control, neither the Board nor the Committee may terminate
this Plan or amend this Plan in a manner that adversely affects the rights of
any participant of the Plan.

A "Potential Change in Control" shall be deemed to have occurred if the event
set forth in any one of the following paragraphs shall have occurred:

          (a)  the Corporation enters into an agreement, the consummation of
               which would result in the occurrence of a Change in Control;

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          (b)  the Corporation or any Person publicly announces an intention to
               take or to consider taking actions which, if consummated, would
               constitute a Change in Control;

          (c)  any Person becomes the Beneficial Owner, directly or indirectly,
               of securities of the Corporation representing 15% or more of
               either the then outstanding shares of common stock of the
               Corporation or the combined voting power of the Corporation's
               then outstanding securities (not including in the securities
               beneficially owned by such Person any securities acquired
               directly from the Corporation or its Affiliates); or

          (d)  the Board adopts a resolution to the effect that, for purposes of
               this Plan, a Potential Change in Control has occurred.

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                                                                    Attachment I

                ANNUAL PERFORMANCE PLAN - POOL FUNDING GUIDELINE

                      CORPORATE AND BUSINESS UNIT EARNINGS

2003 Corporate and Business Unit Earnings Target

The 2003 Annual Performance Plan Corporate Earnings Target and the respective
Business Unit Earnings Target include the accrual for payments which may be made
under the Plan's provisions.

Corporate and Business Unit Performance

The distribution of the Annual Performance Plan award pool within the Business
Unit is fully discretionary and will be determined by Business Unit Management.

The pool of funds available will be divided into two equal amounts. One-half of
the pool is based on the Corporate Earnings Target, and the other half is based
on Business Unit performance. Management reserves the right to either increase
or decrease the funding amounts and may reference the following as a general
guideline:

For each percent change in net income above/below the respective earnings
target, the pool amount shall change by: 1% for each percent between 0% - 5%, 2%
for each percent between 5.1% - 10%, 3% for each percent between 10.1% - 15%,
and 4% for each percent between 15.1% - 20%.

          ==========================================================
             % of Net Income Target       % of Pool Amount Funded
          ----------------------------------------------------------
                      120%                          150%
          ----------------------------------------------------------
                      115%                          130%
          ----------------------------------------------------------
                      110%                          115%
          ----------------------------------------------------------
                      107%                          109%
          ----------------------------------------------------------
                      105%                          105%
          ----------------------------------------------------------
                      103%                          103%
          ----------------------------------------------------------
                      100%                          100%
          ----------------------------------------------------------
                       97%                           97%
          ----------------------------------------------------------
                       95%                           95%
          ----------------------------------------------------------
                       93%                           91%
          ----------------------------------------------------------
                       90%                           85%
          ----------------------------------------------------------
                       85%                           70%
          ----------------------------------------------------------
                       80%                           50%
          ==========================================================

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