Thirty seven infants were identified with bronchopulmonary dysplasia (BPD). Their hospital records were examined and survivors evaluated to determine the neurologic aspects of BPD. Five infants exhibited progressive neurologic disease; nine infants, Five infants exhibited progressive neurologic disease; nine infants, nonprogressive neurologic disease; and 19, normal neurologic outcome. In four, neurologic outcome was indeterminate because of early death. Thus, evaluation of this population of infants with BPD has established two syndromes of neurologic disease--progressive and nonprogressive. The patients with nonprogressive neurologic disease exhibited static neurologic deficits identical to those described in earlier reports of outcome in infants with BPD. The infants with apparently progressive neurologic disease had clinical courses comparable to the fatal pattern of cerebral deterioration previously described. The syndromes appear to be distinct in etiology and clinical presentation. Intraventricular hemorrhage complicated by hemorrhagic intracerebral involvement appears the factor most clearly associated with nonprogressive neurologic disease. The etiology of the striking progressive neurologic syndrome could not be so clearly established but appears to be related to the course and treatment of BPD.