In summary, long-term studies of DFO therapy in multiply-transfused patients with beta-thalassemia major have clearly shown it to be generally safe and effective. Appropriate use of DFO can remove excess iron, prevent iron-induced organ damage, and improve survival in thalassemia patients. Patients who begin treatment at a young age can be protected from the lethal complications of iron overload for at least two decades, but chelation therapy may not always prevent or ameliorate late growth failure and/or delayed or absent puberty. Those with iron damage to the heart and possibly other organs may experience stability or improvement in function with intense chelation. High-dose intravenous DFO produces a rapid decrease in hepatic iron content and improved cardiac function but can also cause severe toxicity, as can normal doses in patients with a low iron burden. Continuing studies of DFO are necessary to help further define its long-term efficacy and toxicity. In particular, significant attention should be paid to new strategies aimed at fostering improved compliance with its use.