Little research has been done on consent in clinical management of cancer in children. Many parents think that the informed-consent process is helpful but often confusing; discussions regularly prove more helpful. It can be difficult for parents to understand the notion of randomisation, not to mention the request for consent to this procedure. In this essay, we discuss the clinical problems that arise in the informed-consent process for treatment and research in paediatric oncology and that need an understanding of bioethical issues and psychological principles. We suggest that the process of informed consent is managed as a negotiated shared-consent process, using the problem-based learning method as a guide. Our model provides appropriate and honest information to children and adolescents through easy-to-understand dialogues with the doctor and we propose that medical students and doctors receive specific skills instruction in communications, relational behaviour, and ethics.