President Xi Jinping of China announced today during a visit to the White House that China will start a national cap-and-trade program to limit greenhouse gas emissions in 2017.

Under cap-and-trade programs, a governing body limits the amount of pollution that can be emitted, and then sells permits to companies that want to emit pollutants. Companies can trade their permits, creating a market for emissions and providing an economic incentive for companies to reduce their carbon footprint.

The announcement comes on the heels of last November's climate accord between the U.S. and China, which included a first-ever pledge by China to curb its growing emission rates by 2030. China's cap-and-trade program will help the country reduce emissions from some of its most polluting sectors, including power generation, iron and steel, and chemicals.