After completion of a pilot phase in 1988, the liver tumour study HB89 of the German Society of Paediatric Oncology started on January 1st, 1989. Up to the end of 1990, 54 children with a primary tumour of the liver where enrolled into the study. Thirty-six of them suffered from hepatoblastoma, 8 from hepatocarcinoma. Thirteen of the hepatoblastomas could be resected primarily, 17 were removed following preoperative chemotherapy. One patient with a stage III hepatoblastoma underwent successfully liver transplantation. At the end of 1990, 28 patients were in first remission (78%), two were still under chemotherapy, and six had died after tumour progression or relapse. Out of eight patients with hepatocarcinoma, only two with a primarily resected tumour are still in first remission. Chemotherapy with ifosfamide, cis-platinum, and adriamycin (IPA) or with continuous infusion of cis-platinum and adriamycin (PAcont) was effective in hepatoblastomas but not in hepatocarcinomas. Because of the problems of preoperative differential diagnosis and judgement of resectability, a primary laparotomy with an open tumour biopsy is necessary. Following the HB89 study protocol with its strategy of graded surgical treatment, the rate of resection was high, the perioperative morbidity low, and no death due to surgery was observed.