Exhibit 24

                                POWER OF ATTORNEY


      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Norman Barham
                  ------------------
                  Norman Barham



                                POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Lewis W. Bernard
                  ------------------
                  Lewis W. Bernard




                                POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Frank J. Borelli
                  ---------------------
                  Frank J. Borelli


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Peter Coster
                  ------------------
                  Peter Coster




                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Robert F. Erburu
                  ------------------
                  Robert F. Erburu




                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Jeffrey W. Greenberg
                  ------------------
                  Jeffrey W. Greenberg


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Ray J. Groves
                  ------------------
                  Ray J. Groves


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Stephen R. Hardis
                  ------------------
                  Stephen R. Hardis


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Gwendolyn S. King
                  ------------------
                  Gwendolyn S. King


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                  /s/ The Rt. Hon. Lord Lang of Monkton
                  -------------------------------------
                  The Rt. Hon. Lord Lang of Monkton


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Lawrence J. Lasser
                  -----------------------
                  Lawrence J. Lasser


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ David A. Olsen
                  ------------------
                  David A. Olsen


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ John D. Ong
                  ------------------
                  John D. Ong


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ Adele Simmons
                  ------------------
                  Adele Simmons


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                  /s/ John T. Sinnott
                  ------------------
                  John T. Sinnott


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ A. J. C. Smith
                  -------------------
                  A. J. C. Smith


                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                  /s/ Frank J. Tasco
                  ------------------
                  Frank J. Tasco

                               POWER OF ATTORNEY

      The undersigned, a Director of Marsh & McLennan Companies, Inc., a
Delaware corporation (the "Company"), does hereby constitute and appoint any one
of A. J. C. Smith, Jeffrey W. Greenberg, Sandra S. Wijnberg and Gregory F. Van
Gundy to be the undersigned's agent and attorney-in-fact, each with the power to
act fully hereunder without the other and with full power of substitution to act
in the name and on behalf of the undersigned:

      To sign or to transmit electronically in the name and on behalf of the
      undersigned, as a Director of the Company, and file with the Securities
      and Exchange Commission on behalf of the Company an Annual Report on Form
      10-K for the year ended December 31, 1999, any registration statements or
      prospectuses for the registration of the Company's common stock and
      related interests to be issued pursuant to the Company's duly adopted
      employee benefit, compensation and stock plans, any registration
      statements for the registration of the Company's common stock for issuance
      in connection with acquisitions or for resale by the holders thereof who
      acquired or will acquire such stock in connection with past or future
      acquisitions, and any amendments or supplements to such Annual Report on
      Form 10-K and such registration statements; and

      To execute and deliver, either through a paper filing or electronically,
      any agreements, instruments, certificates or other documents which they
      shall deem necessary or proper in connection with the filing of such
      Annual Report on Form 10-K, registration statements and prospectuses and
      amendments or supplements thereto and generally to act for and in the name
      of the undersigned with respect to such filings as fully as could the
      undersigned if then personally present and acting.

      IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney
effective the 16th day of March, 2000.


                   /s/ W.R.P. White-Cooper
                  ------------------
                  W.R.P. White-Cooper