Emission Trading is a market-based approach to controlling pollution by providing economic incentives for reducing emissions of greenhouse gases. It allows companies to buy and sell permits that allow them to emit a certain amount of pollutants. If a company reduces its emissions below its limit, it can sell its extra permits to other companies that need them. This system encourages businesses to invest in cleaner technologies and practices, as they can profit from selling unused permits. By creating a financial incentive, Emission Trading aims to lower overall emissions in a cost-effective manner while promoting environmental sustainability.