We describe a method of partial limb salvage for the treatment of large primary malignant tumours of the arm. The tumour-bearing area is resected as a cylindrical segment and the distal arm is then replanted with the necessary shortening. The method is suitable for stage-IIB tumours with or without neurovascular involvement which, because of their extent, could otherwise be adequately treated only by amputation. From 1987 to 1992 we used this method in 12 patients with primary malignant bone or soft-tissue sarcomas. Wide resection margins were achieved in all, but six patients died from their disease at a mean of 21.5 months (6 to 48), none with any local recurrence. Five patients have no evidence of disease at a mean follow-up period of 52.2 months (22 to 78), and one was lost to follow-up at 48 months postoperatively when there was no evidence of disease. The results of the functional evaluation of ten patients with a follow-up of over ten months were excellent in one, good in six and fair in three, by the criteria of Enneking (1987). Recovery after nerve reconstruction was satisfactory in all cases with sensation S3 or higher and motor function M2+ or higher. Detailed evaluation of hand function on the Millesi score rated only 22% (9.6% to 33.7%) as compared with the contralateral side, but the patients were satisfied and refused further operations for the improvement of function. These oncological and functional results allow us to recommend resection-replantation as a valuable alternative to amputation for the treatment of primary malignant tumours of the arm.