FOR THE PURPOSES OF THIS REVIEW, THE VAST AND INCREASINGLY COMPLEX SUBJECT OF HYPERCALCEMIC DISORDERS CAN BE BROKEN DOWN INTO THE FOLLOWING CATEGORIES: (1) Physiochemical state of calcium in circulation. (2) Pathophysiological basis of hypercalcemia. (3) Causes of hypercalcemia encountered in clinical practice: causes indicated by experience at the University of California, Los Angeles; neoplasia; hyperparathyroidism; nonparathyroid endocrinopathies; pharmacological agents; possible increased sensitivity to vitamin D; miscellaneous causes. (4) Clinical manifestations and diagnostic considerations of hypercalcemic disorders. (5) The management of hypercalcemic disorders: general measures; measures for lowering serum calcium concentration; measures for correcting primary causes-the management of asymptomatic hyperparathyroidism.