In the US over 3 million adults or approximately 2.3% of the population between the ages of 18-54 suffers from Obsessive-Compulsive Disorder (OCD), with a prevalence outranking mental disorders such as schizophrenia, bipolar disorder, and panic disorder. This fully revised new edition of both the therapist guide and workbook is completely reformatted and revised to reflect the most current findings in the field of OCD.