Exhibit 10(iv)

               FORM OF AMENDMENT TO EMPLOYMENT SECURITY AGREEMENT
               --------------------------------------------------

     This Amendment, dated as of [insert date], expressly amends that certain
Employment Security Agreement, dated as of [insert date of original agreement]
[and previously amended as of [insert date]], 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;

     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.   Section 1 of the Employment Security Agreement is hereby amended by adding
     the following new clause [(f)][(g)] thereto, as follows:

     [(f)][(g)] Solely for purposes of determining the Executive's eligibility
     to participate in the Company's retiree medical care program, in the event
     that 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 deemed to have up to an additional [twenty-four
     (24)][thirty-six (36)] months of age and/or service credit with respect to
     the Qualified Pension Plan, provided, however, that such additional age
     and/or service credit will only be credited to the Executive to the extent
     that such additional credit would, as of the Executive's Employment
     Termination, enable the Executive to qualify for participation in the
     Company's retiree medical care program. The additional credit described in
     this Section 1[(f)][(g)] shall be deemed to exist only for purposes of
     determining the Executive's eligibility to participate in the Company's
     retiree medical care program and shall otherwise have no effect on the
     Executive's age and service credit under the Qualified Pension Plan. The
     provisions of this Section shall have no effect on the Company's ability to
     amend or terminate the retiree medical care



     program and shall not be construed as requiring the Company to maintain any
     such program in any manner or for any period of time.

     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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