Sleepwalking is one of the parasomnias, a group of disorders that also includes night terrors, nocturnal enuresis and nightmares. This disorder of arousal is much more common in children than in adults, and it is commonly associated with other parasomnias. Sleepwalking typically occurs during the first three hours of sleep, when sleep stages 3 and 4 (non-rapid-eye-movement sleep) are most prevalent. The episodes usually last 30 seconds to 30 minutes. The differential diagnosis of sleepwalking includes partial complex seizures occurring during sleep, rapid-eye-movement behavior disorder, night terrors, malingering, dissociative phenomena and medication effects. The treatment of sleepwalking in children includes providing a regular sleep-wake schedule, ensuring that the child has sufficient sleep and reassuring the parents. Medications and psychotherapy may be indicated in some adult patients.