NO ONE KNOWS what causes schizophrenia. Recent studies involving brain anatomy and brain development will be combined with knowledge about the effects of antipsychotic drugs to someday provide a more complete answer than we can offer today. What we now know, however, provides intriguing clues about possible causes of mental disorders. Far less information is available about possible environmental, sociocultural, or psychological influences on the development of schizophrenia. It is now assumed that biological factors in combination with stresses and outside events contribute to the onset and development of the disease.