This randomized controlled trial will test the efficacy of CBT-I intervention for school-aged children (7-11 years old) with insomnia. The trial will focus on the role of sleep restriction therapy in treatment. Children will be randomized to one of three groups: (1) CBT-I; (2) CBT-I without SRT; or (3) a waitlist control group. Assessments will occur at baseline, mid-treatment, post-treatment, and a 3-month follow up. Some measures (e.g., child motivation) will also be assessed after each therapy session. Insomnia and sleep-wake patterns will be assessed objectively using actigraphy, and subjectively using sleep diaries, a clinical diagnostic interview, and questionnaires. Parent and child questionnaires will be administered to assess moderators and mediators of treatment outcomes.