Much work has been directed at establishing the impact of osteoporosis and related fragility fractures in rheumatic diseases. Several cross-sectional studies reported that disability and reduced motility that are due to functional impairment are among the most important determinants of bone loss in different rheumatic diseases. At the same time, longitudinal studies have confirmed the detrimental effect of uncontrolled disease activity on bone density. In this perspective, the suppression of inflammation probably remains the main concern when considering treatment options. Besides these variables, pharmacologic agents that are used commonly in the treatment of these conditions probably have an adjunctive effect on bone loss in rheumatic patients. Large epidemiologic studies have demonstrated clearly that patients who have RA, SLE, or AS are at an increased risk for fragility fractures. Further studies are required to investigate the effective impact of osteoporosis and fragility fractures in other rheumatic diseases, and to define the relationship between OA and osteoporosis. A better appreciation of the impact and mechanisms of osteoporosis in rheumatic diseases by rheumatologists represents a clinical challenge; however, a greater understanding of this frequent complication will improve the quality of health care and the lives of patients who have rheumatic diseases.