During past years, Korea figured among the OECD countries with the highest share of population exposed to excessive PM2.5 (atmospheric particulate matter that have a diameter of less than 2.5 micrometres) concentrations and PM2.5 concentration level in Seoul is about two times higher than the WHO’s guidelines or the levels of other major cities in developed countries. A number of countermeasures have been recently introduced to address such challenges, including a tightening of air quality standards and increasing local inspection and enforcement capacity. This paper reviews these recent reforms, and discusses possible further improvements. This paper complements two case studies on air quality policies in China and Japan, and a third case study on international regulatory co-operation on air quality in North America, Europe and North-East Asia.