A regional clean air incentives market helps clean up the air in an area by encouraging people to reduce the amount of pollution or emissions they produce. This is done by giving people incentives or rewards, like money, for cutting back on the amount of pollution they make. For example, if you drive a car that produces a lot of pollution, you may be given money to buy a newer, more efficient car that releases less pollution. The money to give these incentives comes from a market in which polluters buy and sell pollution allowances. Polluters who need more allowances can buy them from other polluters who don't need all their allowances. That way, money is used to help reduce pollution in the area, encouraging people to make greener choices.