Adolescence is a developmental period of accelerating physical, psychological, social/cultural, and cognitive development. Many of the adverse health consequences experienced by adolescents are, to a large extent, the result of their risk behaviors. This course provides an overview of this developmental period and describes the epidemiological trends associated with specific risk behaviors. It also describes a broad array of preventive strategies and reviews models of health behavior change and efficacy. In addition, the topic of health services delivery for adolescents are addressed.