I spent most of this month in India, with almost a week in Delhi (more on adventures with Varanasi holy men and in Kerala tea plantations later).

The topic that dominated the public debate in the city during my visit was the city government’s “odd-even scheme,” under which even (odd) numbered cars were only allowed to hit the road on even-numbered dates. The scheme was a pilot that lasted only for two weeks. Each and every Delhite that I met had something to say about the scheme, and it was certainly good fun to try to spot non-compliant vehicles on the road.

Intended to deal with Delhi’s appalling air pollution problem and chronic traffic jams, the odd-even scheme is basically the first policy in Delhi – and maybe in any major Indian city, for that matter – to try to deal with the rapid worsening of air quality. Many a researcher has weighed in on whether the scheme worked.

One analysis by researchers at the University of Chicago and Harvard University found a 18-percent reduction relative to the baseline of surrounding researchers (for geeks: a difference-in-differences design). Another analysis by the Council on Energy, Environment and Water, using a different design and data, found little evidence of benefits.

While these evaluations are useful, I think they are not focused on the most important impact of the odd-even scheme. This is the first time in India’s history that media, policymakers, and citizens are talking seriously about solutions to India’s urban air pollution and traffic problems.

The Delhi government’s scheme is important, first and foremost, because it creates an opening for a debate on long-term solutions to India’s urban problems. Solutions such as congestion charges, improved public transportation, and automobile taxation – along with measures focused on power plants and other sources of air pollution – are now on the table, and advocates of effective policy to protect public health and urban environments have an opportunity to make an important contribution to India’s development.

Whether or not the odd-even scheme “worked” in the sense of marginal reduction in air pollution, I would consider it a clear success in a political sense, and that’s what India needs right now.