China's latest five-year plan shifts its environmental law away from a pollution-control system and towards one that manages environmental quality (see Nature 531, 524–525; 2016). Regional efforts will now be subject to greater oversight to ensure that improvements are implemented across the country and to prevent local corruption.

Under the plan, provincial environmental-protection departments will be responsible for unifying local monitoring and inspection programmes and for eliminating protectionism in local governments (see B. Zhang and C. Cao Nature 517, 433–434; 2015). China's Ministry of Environmental Protection has already established separate environmental-management departments for water, air and soil.

In my view, strict national supervision would help to keep these regional reforms on track and to make them more effective. The US Environmental Protection Agency, for example, manages pollution through permits and defined standards. Ten regional offices work with individual states to implement these regulations. The agency can revoke state programmes that fail to fulfil their responsibilities.

In China, the unified supervision of local monitoring and inspection by provincial environmental-protection departments, which then report to the ministry, is an important step towards improving environmental quality. However, each of the links in this chain must strictly enforce the regulations and work with the rest to clean up the country's environment.