This book is designed to present a comprehensive and state-of the-art update that covers the pathophysiology, epidemiology, and clinical presentation of the most frequently encountered STIs in adolescence and young adulthood. The introductory sections discuss more general themes including approaches to obtaining a sexual history and exam, concerns of sexual minority youth, ethical and legal considerations, and health disparities in STIs in this population. Subsequent chapters are organized by pathogen such as herpes simplex virus, and human immunodeficiency virus, or clinical syndrome including pelvic inflammatory disease, and vaginitis. Each chapter begins with a case study to illustrate key characteristics of the disease process in question and includes rich illustrations, resources, and guidelines.