The federal government has funded work to address global climate change for more than four decades. An initial focus on science has expanded to encompass both mitigation and adaptation, involving at least 18 agencies plus the Executive Office of the President. The work supported is conducted by universities, national laboratories, private contractors, non-governmental organisations, and some federal agencies. Most of the funding has supported scientific and, since the 1990s, technological research and development. Given uncertainties regarding the risks of future climate change, the federal climate strategy has aimed at improving the information available for decision-making and reducing the costs of technologies that could help abate the risks. A growing component has been federal planning and efforts to adapt to climate change. Complementing the science and technology initiatives have been regulatory actions; programs to build capacity in private, state, local, and international entities to address climate change; and tax incentives to stimulate deployment of low greenhouse gas-emitting technologies. This book summarises direct federal funding identified as climate change-related from FY2008 enacted funding through FY2013 and the FY2014 request. It reports the Administration's estimates of tax revenues not received due to energy tax provisions that may reduce GHG emissions and identifies the programs and funding levels, as well as some qualifications and observations on reporting of federal funding, and offers some issues that members of Congress may wish to consider in deliberating U.S. climate change strategies.