The World Health Organization, the United Nations specialized agency for health, was established in 1948 with the objective of the attainment by all people of the highest possible level of health. Health is defined in its constitution as a state of complete physical, mental and social well-being and not merely the absence of illness or infirmity. It is governed by 192 Member States through the World Health Assembly, whose main tasks are to approve the World Health Organization programme and budget for the following two years and to decide major policy questions.