This chapter provides an overview of the concept of acculturation and reviews existing evidence about the possible relationships between acculturation and selected health and behavioral outcomes among Latinos. The effect of acculturation on Latino health is complex and not well understood. In certain areas - substance abuse, dietary practices, and birth outcomes - there is evidence that acculturation has a negative effect and that it is associated with worse health outcomes, behaviors, or perceptions. In others - health care use and self-perceptions of health - the effect is mostly in the positive direction. Although the literature, to date, on acculturation lacks some breadth and methodological rigor, the public health significance of findings in areas in which there is enough evidence justifies public health action.We conclude with a set of general recommendations in two areas - public health practice and research - targeted to public health personnel in academia, community-based settings, and government agencies.