SummaryPostmenopausal osteoporosis is a major public health problem. Women at increased risk can now be detected, enabling effective therapeutic intervention. Hormone replacement therapy is well established for the prevention and treatment of osteoporosis, but alternative treatments are necessary. Calcitonin is an anti-resorptive peptide hormone which has been shown to prevent postmenopausal bone loss. Calcitonin can now be administered by intranasal spray and has been shown to be effective in the treatment of osteoporosis. It may be particularly useful in older women who are less tolerant of hormone replacement therapy.