The World Health Organization (WHO) is the coordinating health authority of the United Nations (UN), which functions to provide global leadership on matters concerning international public health. When the UN was formed by diplomats in 1945, they discussed creating a global health organization, which resulted in the WHO, the successor organization to the League of Nations Health Organization. Its constitution was established on April 7, 1948, a date that is now recognized as World Health Day. As of 2016, 194 countries were members of WHO. WHO’s headquarters are located in Geneva, Switzerland. WHO has six regional offices located in Africa, Europe, Southeast Asia, the Eastern Mediterranean, the Western Pacific, and the Americas, and a Global Service Center in Malaysia. This entry first discusses the work ...