Chronic pelvic pain is defined by the American College of Obstetricians and Gynecologists (ACOG) as noncyclic pelvic pain of at least 3 months duration or cyclic pain of 6-month duration, either of which interferes with one's normal activities of daily living. Dysmenorrhea, or painful menses, is the most common gynecologic complaint among adolescent and young adult females and is the leading cause of recurrent short-term school or work absenteeism. This chapter reviews the assessment, diagnosis, and treatment of some of the most common causes of pelvic pain in adolescents.