This study evaluates the effectiveness and cost of China’s first serious air pollution control policy. It confirms that SO2 emissions in China reduced by 11% during the 2006-2010 period, predominantly achieved through the shutdown of inefficient and small thermal power plants. As the abatement costs for SO2 is cheaper in some provinces, the paper suggest China’s government could double the efficiency of SO2 emissions reductions at the margin by allocating reduction targets across provinces, which could be achieved through an emissions trading scheme. Download the full report on the LSE website.