Nine children with nesidioblastosis underwent pancreatic resection at St. Louis Children's Hospital. Four of these underwent 99 percent of near-total resection. Only one child required permanent insulin therapy postoperatively. Pathologic examination of the resected pancreases revealed a diffuse disturbance of the pancreatic architecture. Prolonged hypoglycemia can have devastating neurologic sequelae. Based on clinical experience and the pathologic demonstration of a diffuse process in the affected pancreas, it is advocated that near-total (99 percent) pancreatectomy is the primary procedure of choice for this disease.