Abstract Background:?Renal replacement therapy (RRT) for acute renal failure (ARF) may be provided in many settings within the hospital. Such patients require a high level of care and often have a poor prognosis. No prospective studies have accurately defined this population, making the prediction of necessary resources and the planning of services difficult. Aim:?To ascertain the incidence, causes and outcomes of acute renal failure requiring renal replacement therapy in Scotland.