The Industrial Emissions Directive (IED) is a piece of European Union (EU) legislation that aims to regulate and reduce the environmental impact of industrial activities. The directive sets out measures to prevent or reduce emissions of pollutants to air, water, and soil, and to promote the use of best available techniques (BAT) in industrial processes. The IED covers a wide range of industrial sectors, including energy production, chemical production, waste management, and intensive farming. It requires industrial operators to obtain permits to operate, which set out emissions limits and other environmental conditions that they must comply with. The directive also includes provisions for monitoring and reporting of emissions and the establishment of national registers of industrial emissions. The IED has been in force since 2010 and is periodically reviewed to ensure its effectiveness and to incorporate new technologies and scientific knowledge.