Although calcitonin has an established place in the treatment of Paget's disease of bone and certain disorders of calcium homeostasis, its most exciting clinical application is in the management of postmenopausal and senile osteoporosis. This disorder affects a vast number of women and, with the increasingly aging population, imposes a heavy burden on health care systems. Although other therapies for osteoporosis and other disorders of bone turnover (e.g., bisphosphonates, fluoride) are in use, many questions remain to be answered concerning their side effects and long-term safety, whereas salmon calcitonin is of proven safety. The introduction of salmon calcitonin nasal spray is a significant therapeutic advance, and the development of other noninjectable preparations will further increase the acceptability of calcitonin to patients and physicians alike.