Exhibit Number (10)(i)
                                                            To 3/31/97 Form 10-Q


                           NORTHERN TRUST CORPORATION

                            ANNUAL PERFORMANCE PLAN

                                      1997

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 and its subsidiaries (hereinafter referred to as the
     "Corporation"), 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
     --------

     The Plan is effective from January 1, 1997 to December 31, 1997.

III. Eligibility and Participation
     -----------------------------

     Eligibility to participate in the Plan is restricted to officers with the
     title of Vice President and above and 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 and Determination
     -------------------------------

     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
     Corporation'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 personnel, the available funding for awards will be based entirely
     on the financial achievement of the Corporation versus the Corporate
     Earnings Target. The formula determining the pool level funding based on
     Corporate and Business Unit performance is described 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,
     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 VIII (h) 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 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)  Awards paid under the provisions of the Plan are considered 
          pensionable earnings when paid.

     (b)  Termination of employment by a participant during the Plan year,
          either voluntary or involuntary with case, and for reasons other than
          death, disability, or retirement shall result in immediate exclusion
          from the Plan.

     (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.

     (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.

     (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.

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     (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.

     (h)  Notwithstanding any other terms contained herein, in the event of a
          Change in Control of the Corporation, discretionary awards shall be
          paid to participants in accordance with the last sentence of Section
          VI of this Plan and as if the Corporation and Business Units had
          achieved the respective earnings targets, as described in Section IV.
          For purposes of this paragraph, a "Change in Control" of the
          Corporation shall be deemed to occur on the earliest of:

          (i)   The receipt by the Corporation of a Schedule 13D or other
                statement filed under Section 13(d) of the Securities Exchange
                Act of 1934, as amended (the "Exchange Act"), indicating that
                any entity, person, or group has acquired beneficial ownership,
                as that term is defined in Rule 13d-3 under the Exchange Act, or
                more than 30% of the outstanding capital stock of the
                Corporation entitled to vote for the election of directors
                ("voting stock");

          (ii)  The commencement by an entity, person or group (other than the
                Corporation or a subsidiary of the Corporation) of a tender
                offer or an exchange offer for more than 20% of the outstanding
                voting stock of the Corporation;

          (iii) The effective time of (A) a merger or consolidation of the
                Corporation with one or more other corporations as a result of
                which the holders of the outstanding voting stock of the
                Corporation immediately prior to such merger or consolidation
                hold less than 60% of the voting stock of the surviving or
                resulting corporation, or (B) a transfer of substantially all of
                the property of the Corporation other than to an entity of which
                the Corporation owns at least 80% of the voting stock; or

          (iv)  The election of the Board of Directors of the Corporation,
                without the recommendation or approval of the incumbent Board of
                Directors of the Corporation, or the lesser of (A) three
                directors or (B) directors constituting a majority of the number
                of directors of the Corporation then in office.

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