Since the 1970s, state governors and legislatures have often led the way on energy policy, from appliance standards to public benefit efficiency programs. States have been the laboratories of progress on energy efficiency and have paved the way for federal policies built on successful state efforts. This report documents state experience in several key policy areas, including building codes, appliance standards, tax incentives, state facilities, public benefits programs, transportation policies, utility regulation, and distributed generation. It indicates potential benefits from a range of policy options, and provides follow up information for states interested in pursuing energy efficiency policies and programs.