The Annual Energy Outlook 2010 (AEO 2010), prepared by the Energy Information Administration (EIA), presents long-term projections of energy supply, demand, and prices through 2035, based on results from EIA's National Energy Modeling System (NEMS). The report begins with an "Executive Summary" that highlights key aspects of the projections. It is followed by a "Legislation and Regulations" section that discusses evolving legislative and regulatory issues, including a summary of recently enacted legislation, such as the American Recovery and Reinvestment Act of 2009 (ARRA). The next section, "Issues in Focus," contains discussions of selected energy topics. The "Market Trends" section summarizes the projections for energy markets. The analysis in AEO 2010 focuses primarily on a Reference case, Low and High Economic Growth cases, and Low and High Oil Price cases. Results from a number of other alternative cases also are presented, illustrating uncertainties associated with the Reference case projections for energy demand, supply, and prices. Complete tables for the five primary cases are provided in Appendixes A through C. Major results from many of the alternative cases are provided in Appendix D