Asia is currently experiencing rapid increases in industrialization, urbanization, and vehicularization. As a result, emission trends (e.g., energy, fuel, vehicle use), population trends (e.g., degree of urbanization, urban population growth, city size), health trends (e.g., age structure, background disease rates), and other important factors (e.g., broad changes in regulatory approaches, improvements in control technology) will influence the extent to which exposure to air pollution affects the health of the Asian population over the next several decades.