Of 569 infants referred to the Children's Orthopedic Hospital and Medical Center Apnea Program (Seattle) for evaluation between 1978 and 1983, a total of 232 were discharged with cardiopulmonary monitors. Of these, 164 (71%) were at 38 weeks' gestation or more (term). In all, 203 (88%) presented with an episode in which vigorous stimulation or resuscitation was used to terminate the event. The mean age of the infants at first episode was 43 days. In 226 (97%) of the infants there was resolution of apnea symptoms by 1 year of age. During this interval, five infants died. Those infants who presented with severe episodes continued to have severe episodes at home and had a longer mean duration of monitoring than those presenting with milder symptoms.