To assess physician decision-making in triage for intensive care and how judgments impact on patient survival. Prospective, descriptive study. General intensive care unit, university medical center. All patients triaged for admission to a general intensive care unit were studied. Information was collected for the patient's age, diagnoses, surgical status, admission purpose, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and mortality. The number of available beds at the time of triage and reasons for refused admission were obtained. Of 382 patients, 290 were admitted, 92 (24%) were refused admission, and 31 were admitted at a later time. Differences between admission diagnoses were found between patients admitted or not admitted (p < .001). Patients refused admission had higher APACHE II scores (15.6+/-1.5 admitted later and 15.8+/-1.4 never admitted) than did admitted patients (12.1+/-.4; p < .001). The frequency of admitting patients decreased when the intensive care unit was full (p < .001). Multivariate analysis revealed that triage to intensive care correlated with age, a full unit, surgical status, and diagnoses. Hospital mortality was lower in admitted (14%) than in refused patients (36% admitted later and 46% never admitted; p < .01) and in admitted patients with APACHE II scores of 11 to 20 (p = .02). The 28-day survival of patients was greater for admitted patients compared with patients never admitted (p = .01). Physicians triage patients to intensive care based on the number of beds available, the admission diagnosis, severity of disease, age, and operative status. Admitting patients to intensive care is associated with a lower mortality rate, especially in patients with APACHE scores of 11 to 20.