Fifty-eight consecutive patients admitted to the ICU requiring ventilatory support for respiratory failure were studied. The Therapeutic Intervention Scoring System (TISS) was used daily as an objective measure of the severity of critical illness in each patient. Patients who survived (27 of 58) 8-10 months after admission to the ICU were interviewed in their homes to assess the outcome of their illness. Most survivors were functioning at or above their premorbid level with respect to their activities of self care and community living. Survivors had minimal recall of the pain and anguish of their ICU experience. The financial cost of care was estimated. Of the total ICU cost, 40% was expended on the 27 survivors. The TISS alone could not distinguish survivors from nonsurvivors in this patient population. The major factor determining the outcome of the illness was the age of the patient. More information on the outcome of critical illness in elderly patients is needed.