During the ten years since the publication of the first edition of this volume, progress in neuroscience has had direct and immediate clinical implications in both the pharmacological and psychological arenas in the treatment of one of psychiatry's greatest challenges: obsessive-compulsive disorder (OCD). This second edition seeks to reflect this progress. Chapters include data on the use of all OCD treatments in special populations, such as the strictly religious, the elderly, children, adolescents, and those who are pregnant, and all are illustrated with detailed case histories that highlight specific treatments and diagnostic issues. This edition also includes three new pharmacotherapy chapters that discuss the use of sertraline, paroxetine and citalopram, and updates of the original edition's chapters on clomipramine, fluoxetine and fluvoxamine; an expanded chapter on children and adolescents that incorporates findings in immunological research, with particular regard to paediatric autoimmune neurologic disorders associated with streptococcal infection (PANDAS); and an expanded behavioural therapy chapter encompassing not only detailed treatment plans for both individuals and groups but also empirical data to support their use.