In India’s Gujarat region, regulators recently faced a conundrum: They had strong air-quality standards on the books, and the tens of thousands of industrial facilities in the region were reported by their auditors as being in compliance. And yet, air quality in cities in Gujarat was among the worst in India.

When the regulators asked a team of researchers to work with them to explore how this could be the case, they discovered that plants selected and paid their own auditors, creating a clear conflict of interest. And sure enough, when the researchers double-checked auditors’ work, it turned out that they often ignored or misreported violations. By modifying this structure, and instead having auditors randomly assigned and paid out of a central fund, the conflict of interest was eliminated. The result? Pollution fell by a whopping 28% among the affected plants over the following year—at no extra cost to regulators and with no new technology.

The Gujarat problem is typical in the the developing world, where air pollution can be so bad that one recent study concluded that breathing in Beijing on a bad day is the equivalent of smoking about 25 cigarettes. In fact, the air they breathe is collectively costing 500 million Chinese citizens more than 2.5 billion years of life expectancy.

But, as discovered in Gujarat, effective and efficient enforcement of existing regulations can make serious progress toward reducing pollution, and improving the quality of life in major global cities. All this without unaffordable investments in expensive energy technology or heavy-handed government intervention.

To truly capitalize on this potential, policy makers need access to reliable information in near real time. That’s something they rarely have. But that may be changing, with India again at the forefront. Pollution regulators there have developed the country’s first standards for low-cost and reliable pollution monitoring. This network of continuous emissions monitoring systems is beginning to allow regulators to rapidly pinpoint where pollution is occurring and if policies are working. That kind of information could be the basis of multiple policy innovations—from simply doing a better job of detecting and punishing violations to creating regional pollution emissions trading networks that would rapidly and cost-effectively improve air quality for large whole cities and states…