The volume and quality of research on what we term the religion-health connection have increased markedly in recent years. This interest in the complex relationships between religion and mental and physical health is being fueled by energetic and innovative research programs in several fields, including sociology, psychology, health behavior and health education, psychiatry, gerontology, and social epidemiology. This article has three main objectives: (1) to briefly review the medical and epidemiologic research on religious factors and both physical health and mental health; (2) to identify the most promising explanatory mechanisms for religious effects on health, giving particular attention to the relationships between religious factors and the central constructs of the life stress paradigm, which guides most current social and behavioral research on health outcomes; and (3) to critique previous work on religion and health, pointing out limitations and promising new research directions.