Contamination OCD is a common but challenging-to-treat form of obsessive-compulsive disorder that represents roughly half of its cases. This program teaches clinicians how to treat contamination OCD using the functional-based Mastery treatment approach, a synthesis of exposure and response prevention (ERP), acceptance and commitment therapy (ACT), and emerging literature on the use of judicious safety behaviors to improve functioning in cases where triggers do not directly habituate. This is a humane and well-tolerated approach that is well suited to contamination OCD cases such as disgust, neurodiversity and more, and has now been taught and implemented at major clinics nationwide. This presentation will teach clinicians how to use the Mastery approach, a functional approach to ERP designed for cases that do not respond to traditional ERP, such as disgust or other non-habituating triggers, neurodiversity, co-morbidities and more.