Hi-ASAP is a Future Earth regional initiative to tackle air pollution and health challenges in Asia. The main goal of the initiative is to provide scientific evidence to support effective policy actions to reduce air pollution levels, in particular PM2.5, in Asia and Pacific by applying newly developed low-cost sensing devices. It was developed under the umbrella of the International Global Atmospheric Chemistry project – Monsoon Asia and Oceania Networking Group (IGAC-MANGO) and endorsed as Future Earth activities.