Parasomnias are defined undesirable physical events or experiences that occur during entry into sleep, within sleep or during arousals from sleep. Parasomnias occur more frequently in children than in adults. All parasomnias can be diagnosed based on subjective reports from the patient, parent or caregiver, except for REM sleep behavior disorder where diagnosis requires polysomnographic investigation. This chapter also addresses the main clinical features and most recent treatments of parasomnias.