Research on the causes and impacts of global warming is conducted by organizations at all levels of society: academic institutions, nongovernmental groups, the U.S. and other governments, and international institutions. The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the assessment of climate change. It was established by the UN Environment Program and the World Meteorological Organization in 1988 to provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts. Thousands of scientists from all over the world contribute to the work of the IPCC on a voluntary basis, and governments participate in the review process and the plenary sessions, where main decisions about the IPCC work program are taken and reports are accepted, adopted and approved. The IPCC has released four “assessment reports,” which have been key in moving international climate negotiations forward. The IPCC is now working on the Fifth Assessment Report which will be completed in 2014. In the U.S., the National Academies of Science has issued scores of reports on climate change, including a series of studies requested by Congress entitled “America’s Climate Choices.” The U.S. Global Change Research Program is a collaborative effort involving 13 federal agencies to evaluate the current and future impacts of climate change, inform policymakers and the public about scientific findings, and investigate effective ways to reduce greenhouse gas emissions and deploy cost-effective clean energy technology.