The Energy Efficiency and Conservation Block Grant (EECBG) Program, funded by the American Recovery and Reinvestment Act in 2009, holds important lessons for United States climate policy. A one-time infusion of funding given primarily to local governments to for the purpose of reducing energy use and greenhouse gas emissions, the policy had important but uneven effects. Most recipients were able to show progress on energy efficiency goals to meet program requirements. But communities with pre-existing interest in and experience with climate and energy programs tended to multiply the effects of the funding, using it to launch long-term efforts or prove concepts in order to secure further funding and support. The dissertation shows the value of communities' participation in voluntary policy initiatives related to climate and energy, as municipalities with even a small amount of related experience were better positioned to turn a one-time infusion of federal funding into long-lasting programs.