Written for clinicians, this book presents in detail the diagnosis, clinical picture, pharmacotherapeutic and psychotherapeutic treatments for obsessive-compulsive disorder and disorders traditionally included in an obsessive-compulsive spectrum. The book draws on the author’s extensive experience as well as reviewing the published evidence, including controlled trials, case series and case reports. Each chapter ends with treatment planning guidelines summarizing appropriate evaluation and treatment strategies. An extended chapter details the use of all medications that have been reported effective for these disorders and the management of common and uncommon drug interactions and side effects. The book’s appendices contain useful symptom rating scales, provide access to mental health organizations and to printed and internet materials for patient education, and list international proprietary names for the drugs discussed. This is an essential resource and practical guide to treatment planning for psychiatrists and other mental health professionals, whether they favor pharmacological or cognitive-behavioral approaches.