In all human societies, beliefs and practices relating to illness are a central feature of a community. Often these are linked to beliefs about the origin of a much wider range of misfortune, of which illness is just one form. In some societies the whole range of these misfortunes is blamed on supernatural forces, or on divine retribution or on the malevolence of a witch or sorcerer. One cannot really understand how people react to illness, death or misfortunes without an understanding of the type of society they have grown up. A health care system is a social institution that involves the interaction of a number of people, minimally the patient and the curer. The manifest function of a health care system is to mobilize resources of the patient, his family and his society to bring them to bear on his problem. A health care system obviously reflects the logical and philosophical characteristics of the diseases and ill health, causality system with which it is linked. How people in different societies and social groups explain the causes of ill health, the types of treatment they believe in, and to whom they turn to if they do get ill is core of medical anthropology.