Research on the development and impacts of air transport has hitherto focused mainly on developed countries in the Global North, and relatively little on less developed countries in the Global South. The seven papers of this Special Issue of the Journal of Transport Geography aim to address this imbalance and encourage further research on air transport development in the Global South. In recent years, the Global South has witnessed significant changes in air transport networks and policies, with implications for economic growth, spatial development and airline business models. This Special Issue explores some challenges to air transport development in the Global South for countries in Africa, South America, the Middle East and Asia, including links between air transport and economic development, the evolution and key drivers of air transport growth and the spatial distribution of passenger airline networks, and the development and impact of low-cost carriers. It also identifies opportunities for future research in this growing area.