We report on 11 consecutive cases of nesidioblastosis successfully managed, in a 22-year period from 1972-1993 at The Children's Hospital, Birmingham, England. In the pre-operative period all patients were managed by constant glucose administration ( > 10 mg/kg/min) and hyperglycaemic agents such as diazoxide, glucagon, growth hormone and somatostatin either singly or in combination. Seven patients underwent partial pancreatectomy, 2 of whom needed a subsequent near-total resection; 4 others had a near-total pancreatectomy as the primary procedure. The 5 patients who have had partial pancreatectomies are healthy and on no regular medication. Of the 6 patients who had near-total pancreatectomy 3 require insulin for diabetes mellitus and 3 are on pancreatin for pancreatic exocrine deficiency. We recommend partial pancreatectomy as the first operation in the treatment of nesidioblastosis.