This report describes a 7-year experience with acute peritoneal dialysis in 31 neonates and infants less than 60 days of age. There were 20 boys and 11 girls, ages 3 to 60 days. Tenckhoff catheters of modified length were placed in the newborn intensive care unit (ICU), pediatric ICU, or surgery suites, and hourly exchanges (20 cc/kg) were started immediately postoperatively. Diagnoses included congenital metabolic disorders (11), acute tubular necrosis (6), postcardiopulmonary bypass with renal failure (5), renal cortical necrosis (5), obstructive uropathy (2), renal agenesis (1), and bilateral renal dysplasia (1). Complications included: peritonitis (4), bowel perforation (1), exit site infection (3), leaking dialysate (4), catheter obstruction (2), inguinal hernias (3), umbilical hernia (1), and retroperitoneal hemorrhage (1). There were 19 deaths (61.3%) from 1 to 90 days postinsertion in this high risk group. The (1), and post liver transplant (1). Effective dialysis (lowering of blood urea nitrogen (BUN) or ammonia, correction of acidosis, decrease in fluid overload) was possible in all cases. Five of the 12 survivors remain on chronic dialysis awaiting renal transplantation. Peritoneal dialysis is effective in the newborn period in the management of metabolic disturbances as well as renal failure. Morbidity and mortality (61.3%) is related to the near-morbid condition of the baby at the time of insertion and the severity of the complex underlying diagnosis often associated with multiorgan failure.