Eighteen patients with community acquired pneumonia required intensive care for severe or progressive hypoxaemia, rising arterial carbon dioxide tension or respiratory arrest, and 17 received intermittent positive pressure ventilation. Thirteen survived to leave hospital and 12 are long term survivors. Ventilation was started within 4 days of admission in all cases and was continued for up to 34 days; six patients required ventilation for over 3 weeks. The most common medical complication was renal failure. The most common iatrogenic complication was pneumothorax. We believe that all the hypoxic patients would have died from their hypoxia had it not been corrected. We estimated that up to 5% of patients admitted with community acquired pneumonia need intensive care. This study demonstrates the effectiveness of such care, which is multidisciplinary, demanding, and may need to be prolonged.