Across the nation, many states and regions have shown strong leadership in creating and implementing policies, programs, and measures that reduce CO2 emissions from the power sector, while achieving other economic, environmental, and energy benefits. These policies and programs can serve as a strong foundation for states developing strategies to reduce greenhouse gas (GHG) emissions. This publication provides an overview of existing state activities that reduce CO2 emissions from the power sector. Policies and programs range from market-based programs and CO2 emissions performance standards that require CO2 emissions reductions from EGUs, to others, such as renewable portfolio standards (RPS) and energy efficiency resource standards (EERS), that reduce CO2 emissions by altering the mix of energy supply and reducing energy demand. States have developed their policies and programs with stakeholder input and tailored them to their own circumstances and priorities. States vary in their regulatory structures, electricity generation, and usage patterns, while geography affects factors such as the availability of fuels, transmission networks, and seasonal energy demand. States have tailored their climate and energy policies and programs accordingly. States also have different economic considerations, drivers, and approaches when implementing climate change, energy efficiency, and renewable energy policies, programs, and measures. This publication is intended to provide background information about strategies states have used to achieve CO2 emissions reductions in the power sector, advance end-use energy efficiency, and increase the use of renewable energy resources.