Hardly a day has gone by in recent months without alerts for fine air concentrations. In January 2018 alone, a total of 36 alerts were issued nationwide for PM10. The number of alerts issued warning of ultra-fine dust (PM2.5) totaled 81 in the same month, a 68.8 percent increase yearon-year. Furthermore, fine dust concentrations exceeding the Korean daily average air quality standard have been frequently reported lately. After the introduction in 1995 of the Air Quality Standard (50 µg/m3), and a series of subsequent legislations, including Special Law on Atmospheric Environmental Improvement(2003), First Basic Plan for Atmospheric Environment Regulation, Second Basic Plan for Atmospheric Environment Regulation (2013), the PM10 concentration level has been on the decline, although not without occasional increases. The PM10 level, however, has nevertheless been persistently higher than the 20 micrograms-per-cubic meter recommended by the WHO. When it comes to PM2.5, the concentration level is higher than the Korean Air Quality Standard (25 µg/m3) and as much as 2.6 times higher than the WHO-recommended 10 µg/m3. Also, the fine dust concentration level is higher in Seoul than in many other major cities around the world: PM10 concentration is 1.4 times, 2.2 times, 2.4 times and 2.8 times higher than in Los Angeles, Paris, London and Tokyo, respectively; PM2.5 concentration 1.9 times, 2.1 times and 2.2 times higher than in Tokyo, London and Los Angeles, respectively.