To study the epidemiology, style of management, and outcome of intensive care patients with acute renal failure requiring replacement therapy in Australia. Prospective epidemiologic study. Australian adult intensive care units providing acute renal replacement therapy. Adult intensive care patients with acute renal failure treated with renal replacement therapy. Demographic and clinical data collection for 3 months. A standardized data collection form for each case of severe acute renal failure was used to collect demographic, biochemical, clinical, and outcome data. Severe acute renal failure affected 299 patients (approximately eight cases per 100,000 adults per year). Among these patients, 99 (33.1%) had impaired baseline renal function, 238 (79.6%) needed mechanical ventilation, and 232 (77.6%) needed continuous vasoactive drug administration. Critical care physicians controlled patient care and renal replacement therapy in 289 cases (96.7%). Critical care nurses performed such therapy alone in 288 (96.3%) cases. Continuous renal replacement therapy was used in 292 (97.7%) patients. There was no nephrological input in 173 (57.8%) cases. Predicted mortality rates were 52.1% by Simplified Acute Physiology Score II, 49.5% by Acute Physiology and Chronic Health Evaluation II score, and 51.9% by an acute renal failure-specific score. Actual mortality rate was 46.8%. Only 25 (15.7%) patients were dialysis-dependent at hospital discharge. Of these patients, 20 (80%) had premorbid chronic impairment of renal function. In Australia, critical care physicians and nurses manage severe acute renal failure with limited consultative nephrological input. Renal replacement therapy is continuous and outcomes are satisfactory. Our findings support the view that this approach to management of severe acute renal failure is safe.