Obsessive-compulsive disorder (OCD) is a relatively common disorder among children and adolescents, and is associated with increased risk for concurrent and future distress and impairment. Many youth who suffer from OCD go undiagnosed or misdiagnosed, and do not attain appropriate treatment in a timely manner. As a result, researchers have focused greater attention to the assessment of pediatric OCD. This paper provides an overview of recent advances in this area, including an introduction to several new assessment instruments. Descriptions of new and commonly used instruments and their clinical/research utility are described. Psychometric properties are also reported. Finally, a critical review is offered of major trends in the assessment of pediatric OCD (e.g., diagnostic interviews, self-report and parent-report measures, and clinician-administered inventories).