There is now convincing evidence that air pollution, especially the particulate matter (PM) fraction, adversely affects children’s health. In general, the health effects of traffic-derived PM are well described in children living in high-income countries. Conversely, studies into the health effects of PM from biomass and solid fuels are limited to children in lower-income countries. As PM from different combustion sources have components in common (e.g. elemental black carbon) – are we able to extrapolate from the research performed in different countries under different exposure conditions? Using lung function growth and vulnerability to infection as examples of health effects of global significance to children, this review addresses the question whether high-income-country research into air pollution can inform effects of pollution in low-income countries and vice versa