<PAGE>

                                           Registration Statement No. 333-
                                                                      ----------
                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                               __________________
                                    FORM S-8
                             REGISTRATION STATEMENT

                                     Under
                           The Securities Act of 1933
                           Northern Trust Corporation
               (Exact name of issuer as specified in its charter)

        Delaware                                       36-2723087
(State of Incorporation)                   (IRS Employer Identification No.)

                50 South LaSalle Street, Chicago, Illinois 60675

         Northern Trust Corporation Supplemental Thrift-Incentive Plan
                              (Full Title of Plan)
                               Peter L. Rossiter,
                  Executive Vice President and General Counsel
                            50 South LaSalle Street
                            Chicago, Illinois 60675
                    (Name and Address of Agent for Service)
                                 (312) 630-6000
  ____________________________________________________________________________



CALCULATION OF REGISTRATION FEE

                                       Proposed      Proposed
                                       Maximum       Maximum
                         Amount        Offering      Aggregate    Amount of
Title of Securities      To Be         Price Per     Offering     Registration
to be Registered (1)     Registered    Share         Price (2)    Fee


Deferred Compensation   $10,000,000      100%       $10,000,000      $2,780
Obligations


(1)  The Deferred Compensation Obligations are unsecured obligations of Northern
     Trust Corporation to pay deferred compensation in the future in accordance
     with the terms of the Northern Trust Corporation Supplemental Thrift-
     Incentive Plan.

(2)  Estimated solely for the purpose of determining the registration fee.
<PAGE>

                                    PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3.  Incorporation of Documents by Reference.

         The following documents are incorporated herein by reference:

         (a)  The Annual Report on Form 10-K of Northern Trust Corporation (the
              "Registrant") for the fiscal year ended December 31, 1998;

         (b)  The Registrant Quarterly Report on Form 10-Q for the quarter ended
              March 31, 1999;

         (c)  The Registrant's Current Reports on Form 8-K filed on January 19,
              April 19, and July 19, 1999; and

         (d)  All other reports filed pursuant to Section 13 of the Securities
              Exchange Act of 1934, as amended (the "1934 Act") since the end of
              the fiscal year referred to in (a) above.

     All documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14
and 15(d) of the Securities Exchange Act of 1934 (the "1934 Act") subsequent to
the date hereof and prior to the termination of the offering of the securities
registered pursuant to this Registration Statement shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of filing of such documents. Any statement contained in a
document incorporated or deemed to be incorporated by reference herein shall be
deemed to be modified or superseded for purposes of this Registration Statement
to the extent that a statement contained herein or in any other subsequently
filed document which also is or is deemed to be incorporated by reference herein
modifies or supersedes such statement. Any such statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of this Registration Statement.

Item 4.  Description of Securities.

     The Northern Trust Corporation Deferred Compensation Obligations
("Obligations") are general unsecured obligations of the Registrant to pay
deferred compensation in the future in accordance with the terms of the Northern
Trust Corporation Supplemental Thrift-Incentive Plan ("Plan") from the general
assets of the Registrant, and rank pari passu with other unsecured and
unsubordinated indebtedness of the Registrant from time to time outstanding.

     The Obligations are not subject to redemption, in whole or in part. The
amount of compensation to be deferred by each participating employee (each a
"Participant") will be determined in accordance with the Plan based on elections
by each Participant. Each
<PAGE>

Obligation will be payable in accordance with the terms of the Plan. The
Obligations will be invested in one or more investment vehicles selected by the
Participant. Each Participant's Obligation will be adjusted to reflect the
investment experience, whether positive or negative, of the selected vehicles,
including any appreciation or depreciation. The Obligations will be denominated
and be payable in United States dollars.

     The Registrant reserves the right to amend or terminate the Plan at any
time, provided that no amendment or termination may directly or indirectly
reduce the balance of any Obligations as of the effective date of the amendment
or termination.

     The Obligations are not convertible into any other obligations of the
Participant. The Obligations will not have the benefit of a negative pledge or
any other affirmative or negative covenant on the part of the Registrant. The
Obligations will be funded by means of a "rabbi trust" for which U.S. Trust
Company, National Association, an independent corporate trustee will serve as
trustee. The trustee will not have the authority for, and each Participant will
be responsible for acting independently with respect to, among other things, the
giving of notices, responding to any requests for consents, waivers or
amendments pertaining to the Obligations, enforcing covenants and taking action
upon a default.

Item 5.  Interests of Named Experts and Counsel.

     Peter L. Rossiter, Executive Vice Present and General Counsel of the
Registrant, has furnished the opinion attached as Exhibit 5 to this registration
statement with respect to the validity of the securities being registered
hereunder. As of July 1, 1999, Mr. Rossiter owned 223,218 shares of Common Stock
of the Registrant, which includes 190,364 shares issuable pursuant to stock
options.

Item 6.  Indemnification of Directors and Officers.

     Section 145 of the Delaware General Corporation Law and Article Eighth of
the Corporation's Restated Certificate of Incorporation provide for
indemnification of the Corporation's directors and officers in a variety of
circumstances, which may include liabilities under the Securities Act of 1933,
as amended (the "1933 Act"). The general effect of these provisions is to
provide that the Corporation shall indemnify its directors and officers against
all liabilities and expenses reasonably incurred in connection with the defense
or settlement of any judicial or administrative proceedings in which they become
involved by reason of their status as corporate directors or officers, if they
acted in good faith and in the reasonable belief that their conduct was neither
unlawful (in the case of criminal proceedings) nor inconsistent with the best
interests of the Corporation. With respect to legal proceedings by or in the
right of the Corporation in which a director or officer is adjudged liable for

                                      -2-
<PAGE>

improper performance of his duty to the Corporation, indemnification is limited
by such provisions to that amount which is permitted by the court. In addition,
the Corporation has purchased insurance as permitted by Delaware law on behalf
of directors, officers, employees or agents, which may cover liabilities under
the 1933 Act.


Item 7.   Exemption from Registration Claimed.

          Not applicable.


Item 8.   Exhibits.

          The Exhibits filed herewith are set forth on the Exhibit Index filed
as part of this registration statement.


Item 9.   Undertakings.

          (a)  The undersigned Registrant hereby undertakes:

               (1)  To file, during any period in which offers or sales are
                    being made, a post-effective amendment to this registration
                    statement:

                    (i)    To include any prospectus required by Section
               10(a)(3) of the 1933 Act;

                    (ii)   To reflect in the prospectus any facts or events
               arising after the effective date of the registration statement
               (or the most recent post-effective amendment thereof) which,
               individually or in the aggregate, represent a fundamental change
               in the information set forth in the registration statement.
               Notwithstanding the foregoing, any increase or decrease in volume
               of securities offered (if the total dollar value of securities
               offered would not exceed that which was registered) and any
               deviation from the low or high and of the estimated maximum
               offering range may be reflected in the form of prospectus filed
               with the Commission pursuant to Rule 424(b) if, in the aggregate,
               the changes in volume and price represent no more than 20 percent
               change in the maximum aggregate offering price set forth in the
               "Calculation of Registration Fee" table in the effective
               registration statement; and

                    (iii)  To include any material information with respect to
          the plan of distribution not previously disclosed in the registration
          statement or any material change to such information in the
          registration statement;

                                      -3-
<PAGE>

          provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
          apply if the registration statement is on Form S-3, Form S-8 or
          Form F-3, and the information required to be included in a post-
          effective amendment by those paragraphs is contained in periodic
          reports filed with or furnished to the Commission by the Registrant
          pursuant to Section 13 or 15(d) of the 1934 Act that are incorporated
          by reference in the registration statement.

               (2)  That, for the purpose of determining any liability under the
          l933 Act, each such post-effective amendment shall be deemed to be a
          new registration statement relating to the securities offered therein,
          and the offering of such securities at that time shall be deemed to be
          the initial bona fide offering thereof.

               (3)  To remove from registration by means of a post-effective
     amendment any of the securities being registered which remain unsold at the
     termination of the offering.

          (b)  The undersigned Registrant hereby undertakes that, for purposes
     of determining any liability under the 1933 Act, each filing of the
     Registrant's annual report pursuant to Section 13(a) or Section 15(d) of
     the 1934 Act that is incorporated by reference in the registration
     statement shall be deemed to be a new registration statement relating to
     the securities offered therein, and the offering of such securities at that
     time shall be deemed to be the initial bona fide offering thereof.

          (c)  Insofar as indemnification for liabilities arising under the 1933
     Act may be permitted to directors, officers and controlling persons of the
     Registrant pursuant to the foregoing provisions, or otherwise, the
     Registrant has been advised that in the opinion of the Securities and
     Exchange Commission such indemnification is against public policy as
     expressed in the 1933 Act and is, therefore, unenforceable. In the event
     that a claim for indemnification against such liabilities (other than the
     payment by the Registrant of expenses incurred or paid by a director,
     officer or controlling person of the Registrant in the successful defense
     of any action, suit or proceeding) is asserted by such director, officer or
     controlling person in connection with the securities being registered, the
     Registrant will, unless in the opinion of its counsel the matter has been
     settled by controlling precedent, submit to a court of appropriate
     jurisdiction the question whether such indemnification by it is against
     public policy as expressed in the 1933 Act and will be governed by the
     final adjudication of such issue.

                                      -4-
<PAGE>

                                   SIGNATURES

The Registrant

     Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all the
requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Chicago and State of Illinois on the 30th day of
July, 1999.

                          NORTHERN TRUST CORPORATION

                          By    /s/ Peter L. Rossiter
                             -------------------------
                                Peter L. Rossiter
                                Executive Vice President and General Counsel

     Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed below by the following persons in the
capacities indicated on the 30th day of July, 1999.


Signature                 Title


WILLIAM A. OSBORN*        Chairman of the Board
------------------        President, Chief Executive
William A. Osborn         Officer and Director


PERRY R. PERO*            Senior Executive Vice President
------------------        and Chief Financial Officer
Perry R. Pero

HARRY W. SHORT*           Senior Vice President
------------------        and Controller
Harry W. Short

DUANE L. BURNHAM*         Director
------------------
Duane L. Burnham

DOLORES E. CROSS*         Director
------------------
Dolores E. Cross

SUSAN CROWN*              Director
------------------
Susan Crown

ROBERT S. HAMADA*         Director
------------------
Robert S. Hamada

                                      -5-
<PAGE>

Signature                 Title


BARRY G. HASTINGS*        Director
---------------------
Barry G. Hastings


ROBERT A. HELMAN*         Director
---------------------
Robert A. Helman


ARTHUR L. KELLY*          Director
---------------------
Arthur L. Kelly


WILLIAM G. MITCHELL*      Director
---------------------
William G. Mitchell


EDWARD J. MOONEY*         Director
---------------------
Edward J. Mooney


HAROLD B. SMITH*          Director
---------------------
Harold B. Smith


WILLIAM D. SMITHBURG*     Director
---------------------
William D. Smithburg


BIDE L. THOMAS*           Director
---------------------
Bide L. Thomas



     *Peter L. Rossiter, pursuant to powers of attorney duly executed by each of
the above Directors and Officers of Northern Trust Corporation and filed with
the Securities and Exchange Commission in Washington, D.C., hereby executes this
registration statement on behalf of each of the persons named above in the
capacity set forth opposite his or her name.


 /s/ Peter L. Rossiter                      July 30, 1999
------------------------
     Peter L. Rossiter
     (Attorney-in-fact)

                                      -6-
<PAGE>

                                 EXHIBIT INDEX



Exhibit
Number        Description                                               Page No.
------        -----------                                               --------


4.1           Restated Certificate of Incorporation
              (Incorporated by reference to Registrant's
              Quarterly Report on Form 10-Q for
              the quarter ended March 31, 1997)

4.2.          By-laws, as amended
              (Incorporated by reference to Registrant's
              Form 8-K dated July 21, 1998)

5.            Opinion of Counsel

23.1          Consent of Counsel
              (Contained in its opinion filed as Exhibit 5)

23.2          Consent of Independent Public Accountants

24.           Powers of Attorney


                                      -7-
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 16693}]
{"company-data": {"conformed-name": "NORTHERN TRUST CORP", "cik": "0000073124", "assigned-sic": "6022", "irs-number": "362723087", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-84085", "film-number": "99674199"}, "business-address": {"street1": "50 S LASALLE ST", "city": "CHICAGO", "state": "IL", "zip": "60675", "phone": "3126306000"}, "former-company": {"former-conformed-name": "NORTRUST CORP", "date-changed": "19780525"}}
Registration Statement No. 333-
                                                                      ----------
                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                               __________________
                                    FORM S-8
                             REGISTRATION STATEMENT

                                     Under
                           The Securities Act of 1933
                           Northern Trust Corporation
               (Exact name of issuer as specified in its charter)

        Delaware                                       36-2723087
(State of Incorporation)                   (IRS Employer Identification No.)

                50 South LaSalle Street, Chicago, Illinois 60675

         Northern Trust Corporation Supplemental Thrift-Incentive Plan
                              (Full Title of Plan)
                               Peter L. Rossiter,
                  Executive Vice President and General Counsel
                            50 South LaSalle Street
                            Chicago, Illinois 60675
                    (Name and Address of Agent for Service)
                                 (312) 630-6000
  ____________________________________________________________________________

CALCULATION OF REGISTRATION FEE

                                       Proposed      Proposed
                                       Maximum       Maximum
                         Amount        Offering      Aggregate    Amount of
Title of Securities      To Be         Price Per     Offering     Registration
to be Registered (1)     Registered    Share         Price (2)    Fee

Deferred Compensation   $10,000,000      100%       $10,000,000      $2,780
Obligations

(1)  The Deferred Compensation Obligations are unsecured obligations of Northern
     Trust Corporation to pay deferred compensation in the future in accordance
     with the terms of the Northern Trust Corporation Supplemental Thrift-
     Incentive Plan.

(2)  Estimated solely for the purpose of determining the registration fee.
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.

         The following documents are incorporated herein by reference:

         (a)  The Annual Report on Form 10-K of Northern Trust Corporation (the
              "Registrant") for the fiscal year ended December 31, 1998;

         (b)  The Registrant Quarterly Report on Form 10-Q for the quarter ended
              March 31, 1999;

         (c)  The Registrant's Current Reports on Form 8-K filed on January 19,
              April 19, and July 19, 1999; and

         (d)  All other reports filed pursuant to Section 13 of the Securities
              Exchange Act of 1934, as amended (the "1934 Act") since the end of
              the fiscal year referred to in (a) above.

     All documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14
and 15(d) of the Securities Exchange Act of 1934 (the "1934 Act") subsequent to
the date hereof and prior to the termination of the offering of the securities
registered pursuant to this Registration Statement shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of filing of such documents. Any statement contained in a
document incorporated or deemed to be incorporated by reference herein shall be
deemed to be modified or superseded for purposes of this Registration Statement
to the extent that a statement contained herein or in any other subsequently
filed document which also is or is deemed to be incorporated by reference herein
modifies or supersedes such statement. Any such statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of this Registration Statement.

Item 4.  Description of Securities.

     The Northern Trust Corporation Deferred Compensation Obligations
("Obligations") are general unsecured obligations of the Registrant to pay
deferred compensation in the future in accordance with the terms of the Northern
Trust Corporation Supplemental Thrift-Incentive Plan ("Plan") from the general
assets of the Registrant, and rank pari passu with other unsecured and
unsubordinated indebtedness of the Registrant from time to time outstanding.

     The Obligations are not subject to redemption, in whole or in part. The
amount of compensation to be deferred by each participating employee (each a
"Participant") will be determined in accordance with the Plan based on elections
by each Participant. Each
Obligation will be payable in accordance with the terms of the Plan. The
Obligations will be invested in one or more investment vehicles selected by the
Participant. Each Participant's Obligation will be adjusted to reflect the
investment experience, whether positive or negative, of the selected vehicles,
including any appreciation or depreciation. The Obligations will be denominated
and be payable in United States dollars.

     The Registrant reserves the right to amend or terminate the Plan at any
time, provided that no amendment or termination may directly or indirectly
reduce the balance of any Obligations as of the effective date of the amendment
or termination.

     The Obligations are not convertible into any other obligations of the
Participant. The Obligations will not have the benefit of a negative pledge or
any other affirmative or negative covenant on the part of the Registrant. The
Obligations will be funded by means of a "rabbi trust" for which U.S. Trust
Company, National Association, an independent corporate trustee will serve as
trustee. The trustee will not have the authority for, and each Participant will
be responsible for acting independently with respect to, among other things, the
giving of notices, responding to any requests for consents, waivers or
amendments pertaining to the Obligations, enforcing covenants and taking action
upon a default.

Item 5.  Interests of Named Experts and Counsel.

     Peter L. Rossiter, Executive Vice Present and General Counsel of the
Registrant, has furnished the opinion attached as Exhibit 5 to this registration
statement with respect to the validity of the securities being registered
hereunder. As of July 1, 1999, Mr. Rossiter owned 223,218 shares of Common Stock
of the Registrant, which includes 190,364 shares issuable pursuant to stock
options.

Item 6.  Indemnification of Directors and Officers.

     Section 145 of the Delaware General Corporation Law and Article Eighth of
the Corporation's Restated Certificate of Incorporation provide for
indemnification of the Corporation's directors and officers in a variety of
circumstances, which may include liabilities under the Securities Act of 1933,
as amended (the "1933 Act"). The general effect of these provisions is to
provide that the Corporation shall indemnify its directors and officers against
all liabilities and expenses reasonably incurred in connection with the defense
or settlement of any judicial or administrative proceedings in which they become
involved by reason of their status as corporate directors or officers, if they
acted in good faith and in the reasonable belief that their conduct was neither
unlawful (in the case of criminal proceedings) nor inconsistent with the best
interests of the Corporation. With respect to legal proceedings by or in the
right of the Corporation in which a director or officer is adjudged liable for

                                      -2-
improper performance of his duty to the Corporation, indemnification is limited
by such provisions to that amount which is permitted by the court. In addition,
the Corporation has purchased insurance as permitted by Delaware law on behalf
of directors, officers, employees or agents, which may cover liabilities under
the 1933 Act.

Item 7.   Exemption from Registration Claimed.

          Not applicable.

Item 8.   Exhibits.

          The Exhibits filed herewith are set forth on the Exhibit Index filed
as part of this registration statement.

Item 9.   Undertakings.

          (a)  The undersigned Registrant hereby undertakes:

               (1)  To file, during any period in which offers or sales are
                    being made, a post-effective amendment to this registration
                    statement:

                    (i)    To include any prospectus required by Section
               10(a)(3) of the 1933 Act;

                    (ii)   To reflect in the prospectus any facts or events
               arising after the effective date of the registration statement
               (or the most recent post-effective amendment thereof) which,
               individually or in the aggregate, represent a fundamental change
               in the information set forth in the registration statement.
               Notwithstanding the foregoing, any increase or decrease in volume
               of securities offered (if the total dollar value of securities
               offered would not exceed that which was registered) and any
               deviation from the low or high and of the estimated maximum
               offering range may be reflected in the form of prospectus filed
               with the Commission pursuant to Rule 424(b) if, in the aggregate,
               the changes in volume and price represent no more than 20 percent
               change in the maximum aggregate offering price set forth in the
               "Calculation of Registration Fee" table in the effective
               registration statement; and

                    (iii)  To include any material information with respect to
          the plan of distribution not previously disclosed in the registration
          statement or any material change to such information in the
          registration statement;

                                      -3-
provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
          apply if the registration statement is on Form S-3, Form S-8 or
          Form F-3, and the information required to be included in a post-
          effective amendment by those paragraphs is contained in periodic
          reports filed with or furnished to the Commission by the Registrant
          pursuant to Section 13 or 15(d) of the 1934 Act that are incorporated
          by reference in the registration statement.

               (2)  That, for the purpose of determining any liability under the
          l933 Act, each such post-effective amendment shall be deemed to be a
          new registration statement relating to the securities offered therein,
          and the offering of such securities at that time shall be deemed to be
          the initial bona fide offering thereof.

               (3)  To remove from registration by means of a post-effective
     amendment any of the securities being registered which remain unsold at the
     termination of the offering.

          (b)  The undersigned Registrant hereby undertakes that, for purposes
     of determining any liability under the 1933 Act, each filing of the
     Registrant's annual report pursuant to Section 13(a) or Section 15(d) of
     the 1934 Act that is incorporated by reference in the registration
     statement shall be deemed to be a new registration statement relating to
     the securities offered therein, and the offering of such securities at that
     time shall be deemed to be the initial bona fide offering thereof.

          (c)  Insofar as indemnification for liabilities arising under the 1933
     Act may be permitted to directors, officers and controlling persons of the
     Registrant pursuant to the foregoing provisions, or otherwise, the
     Registrant has been advised that in the opinion of the Securities and
     Exchange Commission such indemnification is against public policy as
     expressed in the 1933 Act and is, therefore, unenforceable. In the event
     that a claim for indemnification against such liabilities (other than the
     payment by the Registrant of expenses incurred or paid by a director,
     officer or controlling person of the Registrant in the successful defense
     of any action, suit or proceeding) is asserted by such director, officer or
     controlling person in connection with the securities being registered, the
     Registrant will, unless in the opinion of its counsel the matter has been
     settled by controlling precedent, submit to a court of appropriate
     jurisdiction the question whether such indemnification by it is against
     public policy as expressed in the 1933 Act and will be governed by the
     final adjudication of such issue.

                                      -4-
SIGNATURES

The Registrant

     Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all the
requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Chicago and State of Illinois on the 30th day of
July, 1999.

                          NORTHERN TRUST CORPORATION

                          By    /s/ Peter L. Rossiter
                             -------------------------
                                Peter L. Rossiter
                                Executive Vice President and General Counsel

     Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed below by the following persons in the
capacities indicated on the 30th day of July, 1999.

Signature                 Title

WILLIAM A. OSBORN*        Chairman of the Board
------------------        President, Chief Executive
William A. Osborn         Officer and Director

PERRY R. PERO*            Senior Executive Vice President
------------------        and Chief Financial Officer
Perry R. Pero

HARRY W. SHORT*           Senior Vice President
------------------        and Controller
Harry W. Short

DUANE L. BURNHAM*         Director
------------------
Duane L. Burnham

DOLORES E. CROSS*         Director
------------------
Dolores E. Cross

SUSAN CROWN*              Director
------------------
Susan Crown

ROBERT S. HAMADA*         Director
------------------
Robert S. Hamada

                                      -5-
Signature                 Title

BARRY G. HASTINGS*        Director
---------------------
Barry G. Hastings

ROBERT A. HELMAN*         Director
---------------------
Robert A. Helman

ARTHUR L. KELLY*          Director
---------------------
Arthur L. Kelly

WILLIAM G. MITCHELL*      Director
---------------------
William G. Mitchell

EDWARD J. MOONEY*         Director
---------------------
Edward J. Mooney

HAROLD B. SMITH*          Director
---------------------
Harold B. Smith

WILLIAM D. SMITHBURG*     Director
---------------------
William D. Smithburg

BIDE L. THOMAS*           Director
---------------------
Bide L. Thomas

     *Peter L. Rossiter, pursuant to powers of attorney duly executed by each of
the above Directors and Officers of Northern Trust Corporation and filed with
the Securities and Exchange Commission in Washington, D.C., hereby executes this
registration statement on behalf of each of the persons named above in the
capacity set forth opposite his or her name.

 /s/ Peter L. Rossiter                      July 30, 1999
------------------------
     Peter L. Rossiter
     (Attorney-in-fact)

                                      -6-
EXHIBIT INDEX

Exhibit
Number        Description                                               Page No.
------        -----------                                               --------

4.1           Restated Certificate of Incorporation
              (Incorporated by reference to Registrant's
              Quarterly Report on Form 10-Q for
              the quarter ended March 31, 1997)

4.2.          By-laws, as amended
              (Incorporated by reference to Registrant's
              Form 8-K dated July 21, 1998)

5.            Opinion of Counsel

23.1          Consent of Counsel
              (Contained in its opinion filed as Exhibit 5)

23.2          Consent of Independent Public Accountants

24.           Powers of Attorney

                                      -7-