The World Health Organization (WHO) was established in 1948 as a specialized agency of the United Nations responsible for international public health. Its vision is attainment of the highest level of health for all people and its mission is to lead global collaborative efforts to promote equity, combat disease, and improve lives worldwide. WHO is governed by the World Health Assembly and Executive Board and organized into six regional offices and more than 190 country offices. Its priorities include universal health coverage, global health security, addressing social and environmental health determinants, and strengthening institutional capacities for public health.