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