A 53-year-old white woman developed diabetes mellitus. migratory erythema, and anemia, clinical features suggesting the presence of a “glucagonoma.” Ten years earlier, after laparotomy and pancreatic biopsy, she had been told that she had an inoperable pancreatic carcinoma. Review of that biopsy together with current hormonal assays now confirms the diagnosis of glucagonoma. The recurrent peptic ulcer in this patient despite high levels of glucagon, a gastric inhibitory agent, is noted but not explained. An enhanced amylase-creatinine clearance ratio supports the notion that glucagon increases the clearance of amylase.