This is a multi-center, prospective, randomized, parallel-group trial of an intensive strategy vs conventional strategy of renal replacement therapy for the treatment of acute renal failure secondary to acute tubular necrosis in critically ill patients. The primary hypothesis is that the intensive strategy will reduce 60-day all cause mortality by 10% compared to the conventional strategy - i.e.,a reduction from 55% in the conventional arm to 45% in the intensive arm. Secondary outcomes are 60-day in-hospital all-cause mortality, 1-year all cause mortality, and recovery of renal function by day 28. The study will recruit 1164 patients over a period of 3 years, 8 months and each patient will be actively followed for 60 days.