Abstract.Thirty‐six patients with nephroblastoma in Stages I, II and III treated at Radiumhemmet between 1966 and 1973, were analysed. The tumours were classified into three different histological types. All 10 patients in Stage III have developed metastases. All patients in Stages I and II (5 out of 26) who developed metastases had poorly differentiated (histological Type III) tumours. The indications for postoperative irradiation and chemotherapy for the different stages and histological types of the tumour are discusse