Sleep disturbances are highly prevalent among children with psychiatric disorders, making recognition and management of pediatric sleep disorders an important step in improving treatment outcome and preventing relapse of mental illness. This chapter will review the research data on the epidemiology, clinical presentation and treatment approaches for sleep disorders frequently seen in the context of common psychiatric conditions in children and adolescents. Readers will learn about interaction between sleep related problems and symptoms of Attention Deficit/Hyperactivity Disorder, Anxiety and Mood Disorders and Autism Spectrum Disorders, and about the impact of sleep loss and sleep fragmentation on the emotional and behavioral development in children.