Sudden infant death syndrome is the leading cause of death among healthy infants, affecting 0.57 per 1,000 live births. The most easily modifiable risk factor for sudden infant death syndrome is sleeping position. To reduce the risk of sudden infant death syndrome, parents should be advised to place infants on their backs to sleep and avoid exposing the infant to cigarette smoke. Other recommendations include use of a firm sleeping surface and avoidance of sleeping with soft objects, bed sharing, and overheating the infant. Pacifier use appears to decrease the risk of sudden infant death syndrome, but should be avoided until one month of age in infants who are breastfed. The occurrence of apparent life-threatening events does not increase the risk of sudden infant death syndrome, and home apnea monitoring does not lower the risk of sudden infant death syndrome. Supine sleeping position has increased the incidence of flattening of the occiput (deformational plagiocephaly), but this condition can be prevented and treated by encouraging supervised "tummy time," meaning that when awake, infants should spend as much time as possible on their stomachs. All apparent deaths from sudden infant death syndrome should be carefully investigated to exclude other causes of death, including child abuse. Families who have an infant die from sudden infant death syndrome should be offered emotional support and grief counseling.