Pollution prevention means working at the source of pollutants to prevent them from being generated or to reduce the amount generated. It is using materials and energy more efficiently, and conserving natural resources, including water. It is following best management practices, and involving all employees in their implementation, to reduce and prevent pollution. Finally, P2 means also seeing the financial benefits of increased efficiency in the use of raw materials, energy, water or other resources.
The Pollution Prevention on the Web page provides more information.