Book excerpt: Systematic, authoritative, and timely, this is an outstanding reference and text for anyone working with or studying adolescents. More than 50 leading experts comprehensively review current knowledge on adolescent externalizing disorders, internalizing disorders, developmental disorders, personality and health-related disorders, gender identity and sexual disorders, and maltreatment and trauma. Chapters identify the core features of each disorder; explore its etiology, course, and outcome; address diagnostic issues specific to adolescents; and describe effective assessment and treatment approaches. The book also provides an integrative conceptual framework for understanding both healthy and maladaptive adolescent development.