1
                                                                      EXHIBIT 24

                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, with
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ William F. Aldinger
                                  -----------------------------
                                  William F. Aldinger
   2


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Michael J. Birck
                                  -----------------------------
                                  Michael J. Birck
   3


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Marvin G. Brailsford
                                  -----------------------------
                                  Marvin D. Brailsford
   4


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Susan Crown
                                  -----------------------------
                                  Susan Crown
   5

                                        
                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------
                                        

KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ H. Richard Crowther
                                  -----------------------------
                                  H. Richard Crowther
   6


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ W. James Farrell
                                  -----------------------------
                                  W. James Farrell
   7


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Robert C. McCormack
                                  -----------------------------
                                  Robert C. McCormack
   8


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Phillip B. Rooney
                                  -----------------------------
                                  Phillip B. Rooney
   9


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Harold B. Smith
                                  -----------------------------
                                  Harold B. Smith
   10


                            ILLINOIS TOOL WORKS INC.
                                        
                            FORM 10-K ANNUAL REPORT
                                        
                               -----------------
                                        
                               POWER OF ATTORNEY
                                        
                               -----------------


KNOW ALL MEN BY THESE PRESENTS, that the undersigned whose signature appears
below constitutes and appoints W. James Farrell, Harold B. Smith and Stewart S.
Hudnut, and each of them, his true and lawful attorneys-in-fact and agents, wit
full power of substitution and resubstitution for her or him and his or her
name, place and stead, in any and all capacities, to sign the Company's Form
10-K Annual Report and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises, as fully to all intents and purposes as he or she might
or could do in person hereby ratifying and confirming all that said
attorneys-in-fact and agents, or their substitute or substitutes, may lawfully
do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, the undersigned has executed this power of attorney this
19th day of February 1999.

                                  /s/ Ormand J. Wade
                                  -----------------------------
                                  Ormand J. Wade