Over the next decade, a host of federal air regulations will impose restrictions on the emissions of multiple pollutants from stationary sources such as power plants and industrial facilities. These air regulations create a demand for low-cost and rapidly deployable emissions reduction measures and energy efficiency proves to be the least-cost resource when compared with new generation. However, quantifying the emissions benefits from energy efficiency is not straightforward and the multi-pollutant and energy savings benefits from efficiency is often overlooked. To help with this issue, the ACEEE Energy Efficiency and Pollution Control Calculator (EEPC) is intended to help policymakers, state governments, utility operators, and other stakeholders estimate the multi-pollutant air quality benefits of energy efficiency policies and compare both the benefits and the costs with more traditional approaches to reducing pollution. The results provided by this tool are high-level estimates intended to provide the user with an idea of the magnitude of the costs and the impacts of these options on energy use and pollution.