Numerous studies have analyzed data from administrative claims databases to determine persistence and compliance with bisphosphonate therapy for osteoporosis; several of these studies have also examined how persistence and compliance with therapy affect fracture outcomes. All of the studies included in this review demonstrated that patients who were persistent or compliant with therapy had a decreased risk of fracture. None, however, adequately addressed the question of what level of persistence or compliance is necessary to obtain a reduced risk of fracture. There is agreement among studies that compliance and persistence rates are suboptimal for all osteoporosis treatments. Measures to improve persistence and compliance with osteoporosis medications are needed if patients are to achieve the full clinical benefit of treatment.