The Environmental Protection Agency’s (EPA) Clean Power Plan (CPP) continues to garner much attention in the U.S. media, with some voices claiming that the regulation of greenhouse gas emissions falls outside of EPA’s purview. In a presentation at Vanderbilt University, Ken Colburn cuts through some of the confusion about the legal basis of the CPP, examines the requirements of the plan, provides an overview of the numerous compliance options, and looks ahead to the final rule.By prescribing carbon dioxide emission reductions of 30 percent below 2005 levels, the CPP offers a unique opportunity for energy, air, and environmental regulators to work together to rethink power sector regulation in their state or region. Communication between the various stakeholders, neighboring states, and the regional EPA office will be critical in the process. Mr. Colburn encourages officials to consider policy and technology options that reach beyond the four building blocks for compliance set forth by the EPA, to leverage energy efficiency for least-cost, least-risk solutions, to explore multi-state, multi-pollutant plans, and to take advantage of the flexibility afforded CPP compliance plans, which differ from state implementation plans (SIP) under section 110 of the Clean Air Act. Upon finalization of the CPP rule, EPA will issue states an emissions reduction target and will grant broad discretion for crafting a compliance plan best suited to the local conditions and requirements. Upon reviewing the plans, EPA will only impose a federal plan if a state submits an inadequate plan or no plan at all.