The following chapter describes the presentation, impact, and treatment of obsessive compulsive disorder (OCD) in a pediatric population. Similarities and differences in the assessment and treatment of childhood-onset OCD and adult-onset OCD are noted. Children with OCD may struggle with additional mental health conditions such as anxiety, depression, and ADHD. The authors discuss the importance of addressing comorbid mental health conditions and clarify factors that may be involved in differential diagnosis. Additionally, the impact of the family environment and parent-child interactions on children with OCD is reviewed. It is common for pediatric and adult individuals with OCD to involve close family members in OCD-related behaviors in some capacity. Accommodation refers to family members' modification of their own behavior in order to assist in their child's OCD-related rituals. Addressing family accommodation in treatment can substantially impact treatment outcomes in children with OCD. Finally, evidence-based treatment modalities for pediatric obsessive compulsive disorder are explored including cognitive behavior therapy and psychiatric medication.