Hyperparathyroidism is typically diagnosed in the modern era by routine blood chemistry testing with a finding of hypercalcemia. An elevated intact parathyroid hormone (PTH) level generally confirms the diagnosis. Prior to the advent of the sequential multiple analyzer with computer (SMAC) in 1974, the diagnosis was generally made only when the examining physician detected a state of hypercalcemia based on findings such as severe osteoporosis and fractures, recurrent nephrolithiasis, or coma. Nowadays, patients rarely present initially with such symptoms. In fact, patients with early hyperparathyroidism may show borderline results, such as a high normal calcium and high normal PTH level. Although both of these levels may be in the normal range, a high normal PTH and a high normal (unsuppressed) calcium level are abnormal and generally represent the disease of hyperparathyroidism. A dilemma then arises as to whether patients with asymptomatic disease will benefit from surgery, and the equation of risk versus benefit demands a solution of clinical judgment with limited information on outcomes.