The United States can decrease its emissions of carbon dioxide (CO2) to as much as 35 percentbelow1987 levels within the next 25 years by adopting an aggressive package of policies crossing all sectors of the economy. Such emissions reductions will be difficult to achieve and may be costly, but no major technological breakthroughs are needed. In this paper, we identify a ‘‘Tough’’ package of energy conservation, energy supply, and forest managment practices to accomplish this level of emissions reductions. We also present a package of cost‐effective, ‘‘Moderate’’ technical options, which if adopted, would hold CO2emissions to about 15‐percent increase over 1987 levels by 2015. In constrast, if the United State takes not new actions to curb energy use, CO2emissions will likely rise 50 percent during that time. A variety of Federal policy initiatives will be required to achieve large reductions in U.S. CO2emissions. Such policy actions will have to include both regulatory ‘‘push’’ and market ‘‘pull’’ mechanisms‐‐including performance standards, tax incentive programs, carbon‐emission or energy taxes, labeling and efficiency ratings, and research, development, and demostration activities.