Physiological values and interventions in the 24 h before entry to intensive care were collected for admissions from hospital wards. In a 13-month period, there were 79 admissions in 76 patients who had been in hospital for at least 24 h and had not undergone surgery within 24 h of admission to intensive care. Thirty-four per cent of patients underwent cardiopulmonary resuscitation before intensive care admission. Using Acute Physiology and Chronic Health Evaluation II scoring to quantify abnormal physiology in the group as a whole, a significant deterioration in respiratory function before admission was found. During the 6-h period immediately before intensive care admission, 75% of patients received oxygen, 37% underwent arterial blood gas sampling, and oxygen saturation was measured in 61% of patients, 63% of whom had an oxygen saturation of less than 90%. Overall hospital mortality in the study group was 58%. Information collected on the wards identified seriously ill patients who may have benefited from earlier expert treatment.