Etiology, clinical manifestations and outcome were reviewed in 139 cases of "locked-in syndrome." Six cases were reported from our center and the remaining 133 cases were taken from a review of the literature. The results of this review emphasized the necessity for a comprehensive program of pulmonary management in this population. Furthermore, an effective system of communication for the patient is considered essential in the management of the "locked-in" state. Reported mortality in the cases reviewed was 60%. Overall, the prognosis for survival and recovery was found to be better in the group of patients whose syndrome was nonvascular in origin than those with a vascular etiology. Functional recovery was generally good in those patients with a vascular etiology who survived beyond 4 months while recovery occurred earlier and more completely in the nonvascular group. Thus, a program of intensive rehabilitation should be considered early in both groups in order to assist each patient in attaining the highest level of function possible as recovery progresses.