The present application is for continued support for Research Training in Mental Health Epidemiology (originally, Research Training in Psychosocial Epidemiology). The major goal of the program is to provide rigorous training in the application of epidemiologic methods to psychosocial and psychiatric research. Since its inception in 1975, this program has had an unusual degree of stability in its core training faculty and overall objectives. Students who have participated in this program have demonstrated outstanding success in developing careers with important contributions to psychiatric and psychosocial epidemiology. Dr. Stan Kasl has been the Principal Investigator since 1975; however, Dr. Kathleen Merikangas now will take over as Program Director and Dr. Kasl will become Co-Director. The major components of the training include faculty mentoring, formal course work in epidemiology, applied research experience, and clinical practica, where relevant. The present application requests support for 4 pre-doctoral and 4 post-doctoral trainees. Trainees will be recruited to represent the following focal areas: psychosocial epidemiology, psychiatric epidemiology, genetic epidemiology, and biostatistics. The substantive areas of expertise in this program include links between psychosocial risk factors, psychopathology and chronic diseases, comorbidity of psychiatric disorders and substance abuse, genetic epidemiology of behavioral and emotional disorders, and a new future direction of prevention. Faculty interests cover all stages of the life span ranging from childhood to late life. Strengths of this program include: (1) the availability of an excellent formal academic program in the Department of Epidemiology and Public Health including programs in Chronic Disease Epidemiology, Biostatistics, and strong links with other departments including Psychiatry, Psychology and Genetics; (2) an extensive network of ongoing research in diverse areas and across all levels of epidemiology including descriptive, analytic and intervention to provide direct experience in research in psychiatric epidemiology; (3) an interdisciplinary faculty with extensive experience in domains of relevance to psychiatric research including epidemiology, biostatistics, genetics, health policy and services, clinical psychiatry, clinical psychology, developmental psychology and sociology; and (4) focus on four disciplinary areas and four specialty areas that are of critical importance to advances in contemporary psychiatry. Formal training, mentorship, and extensive research experience will provide trainees with the requisite methodologic and substantive tools to conduct high quality research in psychiatry. Exposure to diverse specialty areas both within and between the current program and other ongoing training initiatives will provide a broader perspective on the substantive areas of psychiatric research and appreciation of the need for an interdisciplinary approach that is critical to future progress in understanding the pathogenesis and impact of mental disorders.