Osteoporosis is a serious complication of inflammatory bowel disease which has not received adequate recognition despite its high prevalence and potentially devastating clinical effects. Its pathogenesis remains poorly defined although corticosteroid therapy and sex hormone deficiency are likely to play a major role. Recent advances in the diagnosis and management of osteoporosis have facilitated early detection of bone loss and identified means by which this may be prevented. Bone density measurements to predict fracture risk and define thresholds for prevention and treatment should be performed routinely in patients with inflammatory disease. Hormone replacement therapy is effective in prevention of bone loss in peri- and post-menopausal patients, but the treatment of younger women and men of all ages requires further study.