This handbook synthesizes and integrates the science of internalizing and externalizing childhood disorders with the diagnostic structure of the Diagnostic and Statistical Manual - 5th Edition (DSM-5) of the American Psychiatric Association. It offers a comprehensive overview of DSM-5 disorders in childhood, covering etiology, symptom presentation, assessment methods, diagnostic criteria, and psychotherapeutic and pharmacological approaches to treatment, prognosis, and outcomes. Clinical vignettes and empirical insights illustrate key concepts and diagnostic and treatment issues such as developmental, cultural, gender, and other considerations that may influence diagnosis and case formulation. In addition, chapters on psychosocial therapies offer robust guidelines for working with children and adolescents with DSM-5 disorders. The Handbook also addresses the shift from categorical to dimensional, diagnostic, and treatment systems, particularly focusing on the current shift in funded research in childhood disorders. Topics featured in this Handbook include: Intellectual disabilities and global developmental delay. Depressive disorders in youth. Posttraumatic and acute stress disorders in childhood and adolescence. Autism spectrum and social pragmatic language disorders. Alcohol-related disorders and other substance abuse disorders. Parent-child and sibling relationships. Cognitive-behavioral interventions and their role in improving social skills. The Handbook of DSM-5 Disorders in Children and Adolescents is a must-have resource for researchers, professors, and graduate students as well as clinicians, professionals, and scientist-practitioners in clinical child and school psychology, pediatrics, social work, and educational psychology.