In spite of major technological advances during the past ten years, the gap between rich and poor countries remains considerable. Among the 10.5 million children deaths in 1995, 99% occurred in developing countries and 1% in industrialised ones. Only 5 diseases (pneumonia, diarrhoea, measles, malaria and AIDS), as well as malnutrition, are responsible for more than 60% of the deaths. Most of them could be averted by an equitable access to health care and efficacious prevention programmes in the community. Every year, 3 million children are saved thanks to routine vaccinations, but also 4 millions die because they are not immunised, and this almost exclusively in developing countries. It is therefore urgent to develop strategies aimed at reaching the poorest of the poor, in order to reduce the burden of disease in these population and contribute thus to the well-being of families and to a sustainable economical development.