Air Pollution, especially PM2.5, is a leading cause of many environmental problems including poor health and premature deaths in many developing countries. As per the WHO estimates, globally over 90 percent of people are getting exposed to high levels of air pollution, which causes the deaths of over 7 million people every year. Most deaths are taking place in developing countries including ASEAN countries. Air pollution not only causes impacts on human health and the environment but also cause significant economic loss. Most ASEAN countries are lacking technical capabilities to monitor air pollution, including PM2.5. The ASEAN countries also lack reliable emission inventories, models/tools to assess the impacts, and effective mitigation policies. Sound technical capabilities are required for proper management of air quality and formulation of effective mitigation policies. As air pollution follows no political boundaries and has significant transboundary impacts, there is a need to build technical capacities of the ASEAN countries on air quality management, including recommendations on mitigation policies and strategies. The proposed project aims to build the capacities of the ASEAN countries on air quality management and foster emission reduction of PM2.5. The project will enhance the technical capacities of the ASEAN countries and will support their national efforts for addressing air pollution, which links with achieving the UN 2030 Agenda for the SDGs (3, 4, 7, 11, 13).