NORTHERN TRUST CORP
AMENDMENT TO FORM OF EMPLOYMENT SECURITY AGREEMENT
<DOCUMENT>
<TYPE>EX-10.(IV)
<SEQUENCE>10
<FILENAME>dex10iv.txt
<DESCRIPTION>AMENDMENT TO FORM OF EMPLOYMENT SECURITY AGREEMENT
<TEXT>
<PAGE>

                                                                Exhibit (10)(iv)

              FORM OF AMENDMENT TO EMPLOYMENT SECURITY AGREEMENT
              --------------------------------------------------
                              (Tier 1 Agreement)


          This Amendment, dated as of [insert date], expressly amends that
certain Employment Security Agreement, dated as of  [insert date of original
agreement], by and between Northern Trust Corporation, a Delaware corporation
(the "Company") and [insert name of executive] (the "Executive").

          WHEREAS, effective as of [insert date of original agreement], the
Company and the Executive entered into an Employment Security Agreement
concerning the provision of certain security to the Executive in connection with
any potential change in  control of the Company; and

          WHEREAS, the Company and the Executive desire to amend the Employment
Security Agreement with respect to certain definitions contained therein and
certain other matters;

          NOW, THEREFORE, the Company and the Executive agree as follows:

          Effective as of the date hereof, the Employment Security Agreement is
amended as follows:

          1. The following clause shall be added at the beginning of the first
sentence of Section 1(e) of the Agreement:

          "Whether or not there is a termination of Executive's employment
          entitling him to the other benefits described in this Section 1,"

          1. The following passage shall be added to the end of Section 1(e) of
the Agreement, as follows:

     In addition, each other outstanding equity based award (including stock
     units issued under an ISP) shall become fully vested (and, to the extent
     applicable, exercisable or distributable) upon a Change in Control (or upon
     a termination during a Period Pending a Change in Control under
     circumstances which entitle the Executive to payments and benefits
     hereunder). Notwithstanding anything to the contrary contained in an ISP or
     an option agreement issued pursuant to an ISP, following any termination of
     the Executive's employment


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     entitling him to benefits under this Section 1, (i) all outstanding non-
     qualified stock options granted to the Executive under an ISP and (ii) all
     outstanding incentive stock options granted to the Executive on or
     following September 25, 2001 shall remain outstanding and exercisable until
     the earlier of (a) the exercise of such option by the Executive, (b) the
     fifth anniversary of the Executive's Employment Termination or (c) the
     expiration date of the option term. For the avoidance of doubt, in the
     event of any conflict between the terms of this Section 1(e) and those of
     any outstanding equity based award held by the Executive, the terms of this
     Section 1(e) shall govern.

          1. A new Section 1(g) shall be added to the Employment Security
Agreement, as follows:

     "(g) In the event that the Executive is a participant in the Northern Trust
     Corporation Supplemental Pension Plan (or any successor plan thereto) (the
     "Supplemental Pension Plan"), and the Executive qualifies for neither early
     nor normal retirement benefits pursuant to the terms of The Northern Trust
     Company Pension Plan (or any successor plan thereto) (the "Qualified
     Pension Plan"), the Executive will be credited with up to an additional
     thirty-six (36) months of age and/or service credit with respect to the
     Supplemental Pension Plan, provided, however, that such additional age
     and/or service credit will only be credited to the Executive with respect
     to the Supplemental Pension Plan if and to the extent that such additional
     credit would, as of the Executive's Employment Termination, enable the
     Executive to qualify for early or normal retirement benefits pursuant to
     the terms of the Qualified Pension Plan (if such additional credit were
     taken into account under such plan). Any additional credit shall be applied
     to calculate the Executive's benefit only as specified under the terms of
     the Supplemental Pension Plan. Notwithstanding the foregoing, if the
     Executive's entire benefit under the Qualified Pension Plan is derived from
     the pension equity formula under such plan, no additional credit shall be
     awarded.

          1. Clause (i) of Section 2(a) of the Employment Security Agreement is
hereby restated as follows:

     "(i) Executive's conviction of any criminal violation involving dishonesty,
     fraud or breach of trust which involves the business of the Company or any
     of its subsidiaries;"

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          1. Section 2(a) of the Employment Security Agreement is hereby further
amended by adding the following language following the last sentence thereof:

     "For purposes of clauses (ii) and (v) of this definition, no act, or
     failure to act, on Executive's part shall be deemed "willful" unless done,
     or omitted to be done, by Executive not in good faith and without
     reasonable belief that Executive's act, or failure to act, was in the best
     interest of the Company. In the event of a dispute concerning the
     application of this provision, no claim by the Company that Good Cause
     exists shall be given effect unless the Company establishes to the Board of
     Directors of the Company by clear and convincing evidence that Good Cause
     exists."

          1. Section 2(b) of the Employment Security Agreement is hereby amended
by adding the following language following clause (v) thereof:

     "Executive's continued employment shall not constitute consent to, or a
     waiver of rights with respect to, any act or failure to act constituting
     Good Reason hereunder. For purposes of any determination regarding the
     existence of Good Reason, any claim by Executive that Good Reason exists
     shall be presumed to be correct unless the Company establishes to the Board
     of Directors of the Company by clear and convincing evidence that Good
     Reason does not exist."

          1. Section 2(c) of the Employment Security Agreement is hereby amended
and restated in its entirety, as follows:

     For all purposes under this Agreement (including, without limitation, for
     purposes of the application of the accelerated vesting provision of Section
     1(e) to equity awards granted prior to September 25, 2001), 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:

          (i) any Person is or becomes the Beneficial Owner, directly or
          indirectly, of securities of the Company (not including in the
          securities beneficially owned by such Person any securities acquired
          directly from the Company or its affiliates) representing 20% or more
          of the combined voting power of the Company's then outstanding
          securities, excluding any Person who becomes such a Beneficial Owner
          in

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          connection with a transaction described in clause (A) of paragraph
          (iii) below; or

          (ii) The election to the Board of Directors of the Company, without
          the recommendation or approval of two thirds of the incumbent Board of
          Directors of the Company, of the lesser of: (A) three directors; or
          (B) directors constituting a majority of the number of directors of
          the Company 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 Company
          will not be considered as incumbent members of the Board of Directors
          of the Company for purposes of this section; or

          (iii) there is consummated a merger or consolidation of the
          Corporation or any direct or indirect subsidiary of the Company with
          any other company, other than (A) a merger or consolidation which
          would result in the voting securities of the Company 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
          Company or such surviving entity or any parent thereof outstanding
          immediately after such merger or consolidation, or (B) a merger or
          consolidation effected to implement a recapitalization of the Company
          (or similar transaction) in which no Person is or becomes the
          Beneficial Owner, directly or indirectly, of securities of the Company
          (not including in the securities Beneficially Owned by such Person any
          securities acquired directly from the Company or its Affiliates)
          representing 20% or more of the combined voting power of the Company's
          then outstanding securities; or

          (iv) the stockholders of the Company approve a plan of complete
          liquidation or dissolution of the Company or there is consummated an
          agreement for the sale or disposition by the Company of all or
          substantially all of the Company's assets, other than a sale or
          disposition by the Company of all or substantially all of the
          Company'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 Corpora-

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<PAGE>

          tion in substantially the same proportions as their ownership of the
          Company 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 Company 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 Company immediately following such transaction or series
     of transactions.

          For purposes of the Change in Control definition set forth in this
Section 2(c) and for purposes of Section 2(h) (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 Company 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 Company in substantially the same proportions as their ownership of
     stock of the Company.

          1. Section 2(h) of the Employment Security Agreement is hereby amended
and restated, in its entirety, to read as follows:

     "Period Pending a Change in Control shall be deemed to have commenced if
     the event set forth in any one of the following shall have occurred: (A)
     the Company enters into an agreement, the consummation of which would
     result in the occurrence of a Change in Control; (B)  the Company 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 Corpo-

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     ration representing 15% or more of either the then outstanding shares of
     common stock of the Company 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
     Company or its Affiliates); or (D) the Board adopts a resolution to the
     effect that, for purposes of this Plan, a Period Pending a Change in
     Control has commenced. The Period Pending a Change in Control and shall
     lapse upon the occurrence of a Change in Control or, if earlier (i) with
     respect to a Period Pending a Change in Control occurring pursuant to
     clause (A) of the definition, immediately upon the abandonment or
     termination of the applicable agreement, (ii) with respect to a Period
     Pending a Change in Control occurring pursuant to clause (B) of the
     definition, immediately upon a public announcement by the applicable party
     that such party has abandoned its intention to take or consider taking
     actions which if consummated would result in a Change in Control or (iii)
     with respect to a Period Pending a Change in Control occurring pursuant to
     clause (C) or (D) of the definition, upon the one year anniversary of the
     commencement of the Period Pending a Change in Control (or such earlier
     date as may be determined by the Board)."

          IN WITNESS WHEREOF, Executive and, pursuant to due authorization from
its Board of Directors, the Company have caused this Amendment to be executed as
of the day and year first above written.



                                         NORTHERN TRUST CORPORATION


                                         By
                                           -----------------------------
                                         Name:
                                         Title:



                                         -------------------------------
                                         [Executive]


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