This Encyclopedia covers more than 250 topics, taking a lifespan approach to the fields of public health and prevention. The encyclopedia is divided into four volumes: 1. Foundational Topics; 2. Early Childhood and Childhood; 3. Adolescence; 4. Adulthood and Older Adulthood. Within each volume, issues of illness prevention and health promotion (sometimes referred to as "positive psychology") are addressed in chapter-length entries arranged alphabetically.