The definition, causes and management of acute renal failure in children are described. This includes treatment of both specific and nonspecific problems. The specific problems include hyperkalemia, acidosis, sodium control, hypocalcemia, extracellular volume overload, hypertension, seizures and anemia. Supportive treatment is also considered including continuing assessment of the patient’s status, water and calorie requirements, central venous pressure measurements and transport of patients! The indications for peritoneal dialysis are described and also the technique and possible complications.