Cinacalcet is a calcimimetic agent that is now available for use clinically to manage secondary hyperparathyroidism among patients undergoing dialysis regularly. It acts as an allosteric activator of the calcium-sensing receptor, the molecular mechanism that controls parathyroid hormone secretion. This mechanism of action differs fundamentally from that of the vitamin D sterols, which heretofore have been the only definitive pharmacological intervention for treating secondary hyperparathyroidism.