Inclusion Criteria:  Children and adolescents (ages 6-18) with a primary DSM-5 obsessive-compulsive disorder and at least 1 primary caretaker German-speaking (child & caretakers) Family home equipped with broadband connection and appropriate computer, monitor, HD webcam, and speaker and smart phone written informed content of the child and his caretaker OCD as highest treatment priority  Exclusion Criteria:  IQ below 70 not speaking and understanding German A psychiatric comorbidity that makes participation clinically inappropriate (for example, primary anorexia nervosa), depression with suicidality, psychosis or any other psychiatric disorder that requires acute treatment