An estimated 2-3% of the population is affected by obsessive- compulsive disorder (OCD). This is a chronic condition that significantly affects daily functioning and quality of life. Many people with OCD would greatly benefit from receiving professional help to learn how to successfully manage this debilitating condition. This workbook aims to guide patients of obsessive- compulsive disorder (OCD) in how to best benefit from the treatment provided by their therapists. Treatments addressed in this publication include exposure and ritual (response) prevention, an effective, evidence-based treatment for this disorder. Designed to be used in conjunction with its companion therapist guide titled Exposure and Ritual (Response) Prevention for Obsessive Compulsive Disorder, this Workbook includes an exposure and ritual prevention treatment program which is broken down into 17 - 20 biweekly treatment sessions. During these sessions the patient will be gradually exposed to situations and places that trigger his or her OCD symptoms. The goal is that over time the OCD sufferer comes to realize that the things he or she fears will not necessarily occur if the rituals are not performed. Some exposures will be supervised by the therapist, but the workbook can help the patient to practice on their own at home in order to overcome some of the barriers and difficulties that are part and parcel of every treatment.