Many dialysis modalities such as peritoneal dialysis (PD), hemodialysis (HD) and continuous hemofiltration or hemodialysis (CRRT) are available for the management of pediatric patients with acute renal failure (ARF). PD is a relatively simple, inexpensive modality and can be used in hemodynamically unstable patients. But, it may not be the optimal therapy for patients with severe volume overload or life threatening hyperkalemia. HD is the preferred modality for the treatment of severe volume overload, severe hyperkalemia, but it needs vascular access. Improvements in the HD equipment have allowed HD to be performend in small children. Recents technological improvements in CRRT therapies have enabled pediatric patients who are less stable to be treated. CRRT is becoming the preferred method of acute therapy in pediatric intensive care units. A sound knowledge of the underlying principles of dialysis and awareness of recent technological advancements in differnet dialysis modalities will hopefully result in improved management of children with ARF.