GCs constitute a therapeutic class largely used in clinical medicine for the curative or supportive treatment of various conditions involving the intervention of numerous medical specialties. Beyond their favorable therapeutic effects, GCs almost invariably provoke bone loss and a rapid increase in bone fragility, with its host of fractures. Men and postmenopausal women constitute a preferential target for the bone complications of GCs. The premenopausal status is not, however, a shelter; bone loss also happens in young women who are on GCs. Exposure to GCs yields a fracture risk exceeding the risk conferred by a low BMD per se. Therefore, some reason exists to settle the BMD threshold for therapeutic intervention not at -2.5 T-scores but at -1.0 or -1.5 T-scores, even if no prospective randomized trial so far endorses that opinion. Nowadays, bisphosphonate therapy should be proposed to every patient at risk for fragility fracture, along with calcium and vitamin D supplementation. Studies of other therapeutic modalities (eg, promoters of bone formation) are in progress.