There are many ways of viewing the etiology of mental disease. It can be understood as being due to heredity, due to fixation at infantile levels of instinctual development and faulty early object relationships, due to biological dysfunctions and due to influences arising from interpersonal relationships within the society or culture in which an individual lives. None of these viewpoints is "wrong" but each represents a segmental view of a multilateral process. In the foregoing an attempt has been made to survey our present knowledge regarding the relevance of social and cultural factors to the etiology and treatment of mental illness. In this survey which inevitably had to be incomplete many questions have been raised and few have been answered. It has been shown that the major categories of mental disorders occur ubiquitously, that there is some evidence that they are distributed unevenly, that nosological differences exist between different cultural areas and that differences both in frequency and in nature of clinical manifestations can be related to cultural differences. Methodological difficulties especially of comparative quantitative studies but also of qualitative studies have been pointed out.