The subject of personality—what makes each of us unique and different from one another—has long been a topic of universal fascination. From a medical perspective, research on personality disorders has expanded with the advent of standardized diagnostic systems. This continuing and increased activity and progress in the field spurred the development of this third edition of The American Psychiatric Association Publishing Textbook of Personality Disorders. With an emphasis on updating the information most relevant to clinicians, this new edition features contributions from established experts in the field as well as a new generation of scientists. Dozens of tables, illustrative figures, and real-life case examples summarize the vast data that continue to accumulate in five key areas: • Clinical concepts, including theories of personality disorders, as well as their manifestations, assessment, and diagnosis. This opening section also describes the Alternative DSM-5 Model for Personality Disorders in detail.• Risk factors for, and the etiology and impact of, personality disorders. This section of the book examines data on prevalence, sociodemographics, and levels of functional impairment associated with personality disorders. It offers both a developmental and a genetic/neurobiological perspective and describes the symptomatic and functional outcomes of personality disorders.• Treatment options across therapeutic modalities. A new, cutting-edge chapter argues for the early identification of borderline psychopathology in children and young adolescents, in an effort to prevent full-blown disorder later in life. Additional chapters delve into an array of individual psychotherapies, pharmacotherapeutic options, and group, family, and couples therapies. Guidance on forming and maintaining a therapeutic alliance and on avoiding boundary violations in treating patients with personality disorders is provided.• Special problems, populations, and settings, including suicide, substance use disorders, antisocial behavior, personality pathology in general medical settings, and personality disorders among active-duty military.• The usefulness of translational research to deepen understanding of the biopsychosocial nature of the personality disorders, particularly borderline personality disorder. This comprehensive textbook is an essential resource for clinicians looking to stay on the vanguard of a rapidly growing field.