<p>In this paper, we develop a new way of looking at the New Delhi, India, air pollution regulation problem that pays attention to both the ecological and the economic aspects of this problem. We first construct a theoretical model of air quality in New Delhi. We then show how the dynamic and stochastic properties of air quality in New Delhi can be used to derive two criterion functions for a regulator that are ecologically meaningful. Finally, using these two criteria, we discuss a probabilistic approach to the determination of the optimal length of time during which air quality regulations are in place. In our approach, the objective of the regulator is to maintain the ecological and economic viability of air quality in New Delhi in the long-run.</p>