Seventy-five children undergoing 77 meniscectomies have been reviewed from 1 to 30 years (mean 15) after operation in order to determine the late results of meniscectomy. Arthroscopy of the patients with a poor result was performed at the follow-up. In 30 per cent osteoarthrosis was diagnosed, all with follow-up times from 19 to 25 years. Delay in operation resulted in worse results. The younger the patient the worse the result. The benefit of operation was less in girls than in boys. Bucket-handle lesions and peripheral tears produced the best results after meniscectomy. Fifty-eight per cent of men and 26 per cent of women had symptom-free knees at follow-up. Removing a meniscus is not a benign procedure. Only 44 per cent of patients in whom a damaged meniscus and 17 per cent in whom a normal meniscus had been removed were without symptoms. These results stress the need for making an accurate diagnosis by careful examination and arthroscopy before embarking on meniscectomy in children. Efforts to preserve the meniscus in children must be made whenever possible.