This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the author’s clinical recommendations. A 62-year-old healthy woman presents for routine care. She has no history of fracture, but she is worried about osteoporosis because her mother had a hip fracture at 72 years of age. She exercises regularly and has taken over-the-counter calcium carbonate at a dose of 1000 mg three times a day since her menopause at 54 years of age. This regimen provides 1200 mg of elemental calcium per day. She eats a healthy diet with multiple servings of fruits and vegetables and consumes one 8-oz serving of low-fat yogurt and one glass of low-fat milk almost every day. She recently heard that calcium supplements could increase her risk of cardiovascular disease and wants your opinion about whether or not she should receive them. What would you advise?