Our experience involving 221 consecutive patients with giant-cell tumor who were treated from 1960 to 1982 is reported. Of one group of 146 patients, twenty-seven who were initially treated by wide resection and 112 who had thorough curettage had a recurrence rate of 23 per cent after an average length of follow-up of seven years. All thirty-three recurrences were noted less than six years after operation, and twenty-seven were noted within the first three years postoperatively. Over-all, the type of surgical removal was the most significant factor in recurrence. The recurrence rate was 34 per cent in the patients who had curettage of the lesion and 7 per cent in those who had a wide resection. In a second group of seventy-five patients, initially treated by us for a recurrent tumor, there were fifteen subsequent recurrences, after an average length of follow-up of seven years. Curettage and bone-grafting, with preservation of function of the joint, is the preferred treatment for most patients.