The Energy and Water Development and Related Agencies Appropriations Act, 2010, which was included in the final legislation (H.R. 3183, Public Law 111-85), directed the U. S. Department of Energy (DOE) to develop this report outlining domestic unconventional fossil energy resource opportunities and associated technology applications, in support of overall research, development, and deployment (RD&D) strategy for the further development of these resources. While the strategy report is prepared by DOE, the scope of the RD&D opportunities and associated technology application is nationwide. Based on the current state of ongoing private and public research efforts, the report summarizes: the potential magnitude of the resource base for each of the unconventional fossil energy sources; the technical, safety, and environmental challenges that have been identified in connection with each of the unconventional resources; and the current status of research activity, both public and private, focused on these resources. From this review of past research activity, the report identifies the following principal remaining technological and environmental challenges: production of residual oil that remains in large domestic oil reservoirs while simultaneously storing carbon dioxide (CO2) in those same reservoirs; potential development of the nation's unmineable coal resource via underground coal gasification; the producibility of natural gas from methane hydrate and the potential for simultaneously sequestering CO2; development of gas shale and tight gas sands; application of advance computational methods for evaluating cumulative environmental and socioeconomic impacts of simultaneous development of conventional and unconventional resources on a regional basis; collection and archiving of historical baseline data related to unconventional fossil fuel resources that may facilitate collaborative efforts among researchers; and quantifying the environmental and safety impacts of unconventional resource development and identifying ways to reduce and/or mitigate these impacts, thereby improving environmentally sustainable production of the resources.