The pollution intensity of the Japanese economy, measured as emissions per dollar of GDP, is among the lowest within OECD countries. However, air pollution remains a significant issue. Almost 80% of the Japanese residents were exposed to an annual concentration of PM2.5 above the WHO guideline while the attainment rate of the domestic air quality standard for photochemical oxidants is below 1%. The analysis of the regulatory and enforcement framework for air quality management in Japan identifies best practises and key remaining challenges, including a limited understanding of the generation mechanism of ozone pollution and the need to strengthen cooperation among Prefectures. This paper complements two case studies on air quality policies in China and Korea, and a third case study on international regulatory cooperation on air quality in North America, Europe and North-East Asia.
