World Health Organization The World Health Organization is the United Nations specialized agency for health. It was established on 7 April 1948. WHO's objective, as set out in its Constitution, is the attainment by all peoples of the highest possible level of health. Health is defined in WHO's C onstitution as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity. WHO's goal is the attainment by all peoples of the highest possibl e level of health. It is governed by 192 Member States through the World Health Assembly. The Health Assembly is composed of representative s from WHO's Member States. The main tasks of the World Health Assembly are to approve the WHO programme and the budget for the follo wing biennium and to decide major policy questions.