Purpose of review This review provides an update of the recent progress in etiology, pathogenesis, diagnosis, and treatment of osteonecrosis. Recent findings Concerning pathogenesis, there is evidence that there is a genetic predilection for those who are exposed to the two leading etiologic associations for osteonecrosis: corticosteroids and alcohol. Studies concerning the treatment of osteonecrosis indicate that most preservative (ie, joint-sparing) procedures available today have better results in the precollapse stages of the disease and in smaller lesions. Therefore, researchers continue to develop and modify diagnostic techniques, particularly relating to MRI, for the identification and quantification of osteonecrotic lesions. Advances concerning bone grafting and arthroplasty procedures have resulted in improved clinical outcomes for this patient population. The future treatment of osteonecrosis may involve genetic or cell-based therapies. Summary Although progress has been made, considerably more research is needed before we fully understand this disease. Hopefully, such research will lead to effective measures for saving the femoral head or, better yet, preventing osteonecrosis.