Exhibit 10(iii)

                               SECOND AMENDMENT
                                OF THE RESTATED
                          NORTHERN TRUST CORPORATION
                      SUPPLEMENTAL THRIFT-INCENTIVE PLAN

          WHEREAS, the Northern Trust Corporation (the "Corporation") sponsors
the Restated Northern Trust Corporation Supplemental Thrift-Incentive Plan (the
"Plan"); and

          WHEREAS, pursuant to Section 7.1 of the Plan, the Corporation has the
right to amend the Plan when the Corporation deems such amendment to be
advisable; and

          WHEREAS, the Corporation deems it advisable to amend the Plan;

          NOW, THEREFORE, the Plan is hereby amended as follows:

          1.   Section 1.3 is hereby amended and restated in its entirety, as
follows:

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

               (1)  any Person is or becomes the Beneficial Owner, directly or
               indirectly, of securities of Northern Trust Corporation (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 recapitalization 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

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         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 this Section 1.3 and 1.24 (where applicable) 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.

         2.    Article 1 is amended by redesignating Subsection 1.24 as
               Subsection 1.25.

         3.    Article 1 is amended by adding the following new Section 1.24 as
               follows:

               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;

               (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;

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               (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.

         4.    Section 3.4 is hereby amended by deleting the third sentence
               thereof.

         5.    Section 4.1 is hereby amended by adding the following new
               subparagraph, after the last subparagraph thereof, to read as
               follows:

               Notwithstanding anything in this Plan to the contrary, for a
               period of two years after the date of an occurrence of a Change
               in Control, the Corporation shall not eliminate any of the
               investment elections and choices which were in effect immediately
               prior to the Change in Control and shall not decrease the
               frequency with which Participants may change such investment
               elections. Notwithstanding the foregoing, in the event that an
               investment election is discontinued by its sponsor and therefore
               becomes unavailable to Participants, the Corporation shall
               provide a substitute election with substantially similar
               investment objectives and policies.

         6.    Section 7.1 is hereby amended by adding the following new
               sentence after the last sentence thereof, to read as follows:

               Notwithstanding the foregoing, (i) for a period of two years
               after the date of an occurrence of a Change in Control or (ii) 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. In addition, after the date of the
               occurrence of a Change in Control, no amendment of Section 5.1 of
               the Plan shall be effective with respect

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               to any Participant who is a Participant as of the occurrence of a
               Change in Control without the consent of such Participant.

         This First Amendment to the Plan shall be effective from and after May
16, 2000.


                                               NORTHERN TRUST CORPORATION



                                               By: /s/ Peter L. Rossiter
                                                   ---------------------------
                                               Name: Peter L. Rossiter
                                               Title: Executive Vice President

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