ALTHOUGH hypoparathyroidism is an uncommon disease, numerous reviews of postoperative, idiopathic, and pseudohypoparathyroidism are available.1-8The majority of these reports are reviews of the literature, since few institutions have accumulated a large number of patients with hypoparathyroidism. The purpose of the present communication is to report our experience with 34 patients with hypoparathyroidism observed during a recent ten-year period. Method of Study The records of all patients with a diagnosis of hypoparathyroidism during the period 1954 to 1964 were reviewed. Thirty-four patients fulfilling the following criteria were admitted to the study: The presence of hypocalcemia not due to renal insufficiency, gastrointestinal malabsorption, acute pancreatitis, or osteoblastic metastases. In postthyroidectomy patients, hypocalcemia was required to be present at least 18 months postoperatively to eliminate cases of transient hypoparathyroidism. The presence of a normal or elevated serum concentration of inorganic phosphorus. This criterion was required to eliminate cases of gastrointestinal malabsorption, pancreatitis