This study, identifies and assesses system approaches in order to prioritize research needs for the capture and non-atmospheric sequestering of a significant portion of the carbon dioxide (CO{sub 2}) emitted from fossil fuel-fired electric power plants (US power plants presently produce about 7% of the world`s CO{sub 2} emissions). The study considers capture technologies applicable either to existing plants or to those that optimistically might be demonstrated on a commercial scale over the next twenty years. The research needs that have high priority in establishing the technical, environmental, and economic feasibility of large-scale capture and disposal of CO{sub 2} from electric power plants are:(1) survey and assess the capacity, cost, and location of potential depleted gas and oil wells that are suitable CO{sub 2} repositories (with the cooperation of the oil and gas industry,8409 ); (2) conduct research on the feasibility of ocean disposal, with objectives of determining the cost, residence time, and environmental effects for different methods of CO{sub 2} injection; (3) perform an in-depth survey of knowledge concerning the feasibility of using deep, confined aquifers for disposal and, if feasible, identify potential disposal locations (with the cooperation of the oil and gas industry,8409 ); (4) evaluate, on a common basis, system and design alternatives for integration of CO{sub 2} capture systems with emerging and advanced technologies for power generation; and prepare a conceptual design, an analysis of barrier issues, and a preliminary cost estimate for pipeline networks necessary to transport a significant portion of the CO{sub 2} to potentially feasible disposal locations.