Despite increasing globalisation, international mobility and economic interdependence, 9.7 million children aged less than 5 years in low income countries will die this year, almost all from preventable or treatable diseases. Diarrhoea, pneumonia and malaria account for 5 million of these deaths each year, compared to about 150,000 deaths from childhood cancer in low- and middle-income countries. In high-income countries, 80% of the 50,000 children diagnosed with cancer each year survive, yet cancer remains the leading disease-related cause of childhood death. In low- and middle-income countries, where 80% of children live, the 200,000 children diagnosed with cancer each year have limited access to curative treatment, and only about 25% survive. Some might argue that death from paediatric cancer in poor countries is insignificant compared to death from other causes, and that scarce health resources may be better used in other areas of public health. Is there a role for the treatment of children with cancer in these regions? Do international partnerships or 'twinning' programmes enhance local health care or detract from other public health priorities? What is ethical and what is possible? This review examines the health challenges faced by infants and children in low-income countries, and assesses the role and impact of international paediatric oncology collaboration to improve childhood cancer care worldwide.