This document discusses health issues for three age groups: adolescents and young adults (ages 15-24), adults (ages 25-64), and the elderly (ages 65 and over). For adolescents and young adults, risky health behaviors like unintentional injuries, violence, substance abuse and unsafe sex are major causes of mortality and morbidity. Community health strategies aim to address social and cultural influences on behaviors in this age group. Adults experience most chronic diseases associated with unhealthy lifestyles earlier in life. Community efforts focus on prevention, screening and management of conditions like cancer, heart disease and obesity.