At St. Joseph's Health Centre in London, Ontario, the Departments of Otolaryngology and Endocrinology of the University of Western Ontario work closely together in the medical and surgical management of patients with parathyroid disease. Recently, a multidisciplinary Grand Rounds was held during which current issues in the management of these patients were discussed, with particular emphasis on the role of localization studies as well as the potential difficulty inherent in distinguishing parathyroid adenomas from parathyroid hyperplasia. The following is an edited transcript from the Grand Rounds.