What: United Nations agency specializing in health research, development and advisory action. Established April 7, 1948. Canadian Dr. Brock Chisholm served as director general during WHO's first two terms.

Membership: 192 member states of the United Nations.

Executive: Director General Dr. Gro Harlem Brundtland (2003)

Headquarters: Geneva, Switzerland. Regional offices located in Brazzaville, (Republic of Congo), Copenhagen (Denmark), New Delhi (India), Washington (U.S.), Cairo (Egypt) and Manila (Philippines).

Activities: The World Health Organization is run by health professionals representing all member WHO nations to establish and disseminate intelligence on health issues. Among other things, WHO has developed benchmark procedures for establishing proper sanitary and quarantine procedures, and played a role in stemming the spread of leprosy, cholera, malaria and tuberculosis. Current projects include developing vaccines for malaria and schistosomiasis. The organization also says it intends to eradicate polio.

Here is a look at some of WHO's activities over the years:

• 1948 - WHO established.
• 1951 - WHO member states adopt International Sanitary Regulations (re-named International Health Regulations in 1969). These regulations were enacted to monitor and control cholera, plague, yellow fever, smallpox, relapsing fever and typhus.
• 1979 - After years of battling the disease, WHO certifies worldwide eradication of smallpox.
• 1987 - Responding to the rise in the incidence of AIDS worldwide, WHO launches global program on AIDS.
• 2001 - Immediately following the Sept. 11, 2001, attacks, WHO warns western governments to be on the alert for possible chemical and biological attacks.