Complete surgical resection is essential to long-term survival in children with hepatoblastoma. We present the guidelines from the Children's Oncology Group (COG), liver tumor study group of the Societe Internationale Oncologie Pediatrique (SIOPEL), and German Pediatric Oncology Group (GPOH) for early referral of children with potentially unresectable hepatoblastoma to a specialty center with expertise in extreme resection and liver transplantation. Patients who will become candidates for liver transplantation should receive chemotherapy following the same protocols as for children undergoing a partial hepatectomy. The Pediatric Liver Unresectable Tumor Observatory (PLUTO) is an international prospective database established to collect data and make future recommendations on controversial issues regarding the use of transplant in hepatoblastoma including: 1) What is the optimal treatment of multifocal tumors. 2) What is the role of extreme resection vs. liver transplant in patients with major venous involvement. 3) What is the role of transplant in patients who present with lung metastasis. 3) Should patients with tumor relapse be offered a rescue transplant. 4) What is the role of pre- and post- transplant chemotherapy.