Recent progress in establishing a European network to conduct paediatric oncology phase I/II clinical trials calls attention to the challenges facing researchers developing new agents for children with cancer. These challenges include: ensuring that effective infrastructures are in place to safely and efficiently conduct early phase clinical trials in children while meeting all ethical and regulatory requirements associated with such trials; obtaining timely access to new agents from pharmaceutical sponsors for both preclinical testing and for phase I and phase II testing; and effectively prioritizing new agents for evaluation in children so that those agents most likely to benefit children with specific cancers are brought forward for clinical testing. The use of public funds to develop and maintain clinical trials infrastructures devoted to paediatric oncology drug development can help in addressing these challenges and can facilitate the timely paediatric evaluation of new agents, thereby contributing to the goal of identifying more effective treatments for children with cancer.