EXHIBIT NUMBER (24)
                                                             TO 2002 FORM 10-K


POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS:

     That the undersigned officers and directors of Northern Trust Corporation
hereby severally constitute and appoint William A. Osborn, Perry R. Pero and
Kelly R. Welsh, and each of them singly, our true and lawful attorneys and
agents with full power to them and each of them singly, to sign for us in our
names, in the capacities indicated below, Form 10-K, annual report pursuant to
Section 13 or 15(d) of the Securities Exchange Act of 1934, for the fiscal year
ended December 31, 2002, and to file such Form, with all exhibits thereto and
other documents in connection therewith, with the Securities and Exchange
Commission, hereby granting to such attorneys and agents, and each of them, full
power of substitution and revocation in the premises, and generally to do all
such things in our name and behalf in our capacities as officers and directors
to enable Northern Trust Corporation to comply with the provisions of the
Securities Exchange Act of 1934, as amended, and all regulations of the
Securities and Exchange Commission thereunder, hereby ratifying and confirming
our signatures as they may be signed by our attorneys, or any one of them, to
such Form, and all that our attorneys and agents, or any of them, may do or
cause to be done by virtue of these presents.

     IN WITNESS WHEREOF, the undersigned have hereunto executed this Power of
Attorney This 18th day of February, 2003.


/s/ William A. Osborn
- --------------------------------
    William A. Osborn
    Chairman of the Board, Chief
    Executive Officer, President
    and Director



/s/ Perry R. Pero                    /s/ Harry W. Short
- --------------------------------     -------------------------------------------
    Perry R. Pero                        Harry W. Short
    Vice Chairman                        Executive Vice President and Controller
    and Chief Financial Officer          (Chief Accounting Officer)



/s/ Duane L. Burnham                 /s/ Dolores E. Cross
- --------------------------------     -------------------------------------------
    Duane L. Burnham                     Dolores E. Cross
    Director                             Director



/s/ Susan Crown                      /s/ Robert S. Hamada
- --------------------------------     -------------------------------------------
    Susan Crown                          Robert S. Hamada
    Director                             Director

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/s/ Robert A. Helman                       /s/ Arthur L. Kelly
- ------------------------------             --------------------------
    Robert A. Helman                           Arthur L. Kelly
    Director                                   Director



/s/ Frederick A. Krehbiel                  /s/ Robert C. McCormack
- ------------------------------             --------------------------
    Frederick A. Krehbiel                      Robert C. McCormack
    Director                                   Director



/s/ Edward J. Mooney                       /s/ John W. Rowe
- ------------------------------             --------------------------
    Edward J. Mooney                           John W. Rowe
    Director                                   Director



/s/ Harold  B. Smith                       /s/ William D. Smithburg
- ------------------------------             --------------------------
    Harold  B. Smith                           William D. Smithburg
    Director                                   Director



STATE OF ILLINOIS                   )
                                    )   SS
COUNTY OF COOK                      )


     I, Victoria Antoni , a Notary Public, DO HEREBY CERTIFY that the above
named directors and officers of Northern Trust Corporation, personally known to
me to be the same persons whose names are subscribed to the foregoing
instrument, appeared before me this day in person, and severally acknowledged
that they signed and delivered the instrument as their free and voluntary act,
for the uses and purposes therein set forth.

     GIVEN under my hand and notarial seal this 18th day of February, 2003.


                                                       /s/ Victoria Antoni
                                                       -------------------
                                                           Victoria Antoni
                                                           Notary Public

My Commission Expires:

       7/25/03
- ----------------------

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