We have reviewed ten children who underwent surgical therapy for persistent neonatal hypoglycemia over a 5-year period. All had inappropriately high insulin levels in the face of hypoglycemia, and all failed medical management with intravenous glucose, frequent feeds, diazoxide and glucagon. Two groups of five patients each were analysed retrospectively. Group 1 underwent 95% pancreatectomy, leaving a small amount of pancreatic tissue on the duodenum and common bile duct. The only major complication in this group was in one patient with common duct obstruction requiring choledochoduodenostomy. All these children are developing normally, without diabetes, steatorrhea, or recurrent hypoglycemia. Group 2 underwent 85% pancreatectomy, leaving the uncinate process in situ. Two of these children are well. Two required conversion to 95% resection because of recurrent hypoglycemia; one of these required a subsequent total pancreatectomy, at which time the pancreatic remnant had significantly regenerated. The other Group II patient was normoglycemic but died at age 3 from pneumonia. Pathology in nine cases showed islet cell dysplasia; 5 of these also had microadenomatosis. One case had a histologically normal pancreas. We conclude that 95% pancreatectomy is a safe operation with a lower failure rate than less radical resections, and should be used early in the management of this condition.