There is a popular belief that that air pollution is a problem only in the big, rich cities but does not bother them. We know that PM2.5 is the real killer. However, its measurement does not trace back to a period of ten years across most parts of India. We also now know that there are at least 132 cities across India that do not meet the national air quality standards on any day of the year. There are days when many other cities overtake Delhi in pollution. What is the solution ?