<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                              /S/  ROBERT E. GALLAGHER
                                          _____________________________________
                                                   Robert E. Gallagher

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                               /S/  JAMES J. BRANIFF III
                                          _____________________________________
                                                  James J. Braniff III

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                 /S/  T. KIMBALL BROOKER
                                          _____________________________________
                                                   T. Kimball Brooker

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                  /S/  GARY P. COUGHLAN
                                          _____________________________________
                                                    Gary P. Coughlan

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                               /S/  JAMES W. DURKIN, JR.
                                          _____________________________________
                                                  James W. Durkin, Jr.

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                  /S/  ILENE S. GORDON
                                          _____________________________________
                                                     Ilene S. Gordon

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                               /S/  DAVID E. MCGURN, JR.
                                          _____________________________________
                                                  David E. McGurn, Jr.

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                 /S/  RICHARD J. MCKENNA
                                          _____________________________________
                                                   Richard J. McKenna

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                   /S/  ROBERT RIPP
                                          _____________________________________
                                                       Robert Ripp

<PAGE>

                               POWER OF ATTORNEY

   WHEREAS, ARTHUR J. GALLAGHER & CO., a Delaware corporation (the "Company"),
has prepared and proposes to file with the Securities and Exchange Commission
(the "Commission") under the provisions of the Securities Act of 1933, as
amended (the "Act"), and the rules and regulations promulgated thereunder, a
Registration Statement on Form S-8 (the "Registration Statement"), relating to
the offer and sale of up to 3,300,000 shares of Common Stock, $1.00 par value,
of the Company pursuant to options granted under the Company's 1988
Nonqualified Stock Option Plan and the 1989 Non-Employee Directors' Stock
Option Plan, subject to adjustment as therein provided; and

   WHEREAS, the Company may from time to time file with the Commission under
the provisions of the Act and the rules and regulations promulgated thereunder
Appendices, Amendments and Post-Effective Amendments to the Registration
Statement;

   NOW, THEREFORE, the undersigned hereby:

      (1) designates, constitutes and appoints John C. Rosengren, Vice
   President and General Counsel of the Company, his attorney, with full power
   to act for and on behalf of the undersigned in connection with, and to sign
   the name of the undersigned in his capacity as a Director of the Company to
   the Registration Statement and to any and all Appendices, Amendments and
   Post-Effective Amendments to the Registration Statement which the Company
   may hereafter file with the Commission under the provisions of the Act and
   the rules and regulations promulgated thereunder; and

      (2) ratifies, confirms and approves any and all acts and things which
   John C. Rosengren may lawfully take or do, or cause to be taken or done, by
   virtue of the powers granted to him hereunder.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 30th day of
  April, 2002.


                                                 /S/  JAMES R. WIMMER
                                          _____________________________________
                                                     James R. Wimmer


