The disease spectrum leading to pediatric renal replacement therapy (RRT) provision has broadened over the last decade. In the 1980's, intrinsic renal disease and burns comprised the most common pediatric acute kidney injury (AKI) etiologies. More recent data demonstrate that pediatric AKI most often results from complications of other systemic diseases resulting from the advancements in congenital heart surgery, neonatal care, and bone marrow and solid organ transplantation. In addition, RRT modality preferences to treat critically ill children have shifted from peritoneal dialysis to continuous renal replacement therapy (CRRT) as a result of improvements in CRRT technologies. Currently, multicenter prospective outcome studies for critically ill children with AKI are sorely lacking. The aims of this paper are to review the pediatric specific causes necessitating RRT provision with an emphasis on emerging practice patterns with respect to modality and the timing of treatment, and focus upon the application of the different RRT modalities and assessment of the outcome of children with AKI who receive RRT.