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During the last three years, geologic storage of carbon dioxide (CO 2 ) in saline formations has been demonstrated in three distinct geologic settings by the Midwestern Regional Carbon Sequestration Partnership (MRCSP), one of the seven regional partnerships funded by the U.S. Department of Energy. MRCSP ( www.mrcsp.org ) covers a large region across nine Midwestern and Mid-Atlantic states, with several geologic provinces including: The Michigan and Appalachian Basins, the Cincinnati Arch Province, and the coastal sedimentary layers. Given the long history of coal production, much of the region is heavily dependent on coal-fired plants for electricity, and, therefore, subject to significant economic impact from carbon-emission constraints. The sedimentary formations or geologic structures across the region provide diverse options to mitigate the emissions through geologic storage of CO 2 . The validation for the storage potential comes through field assessments of injectivity and containment at three locations: One each in the Appalachian and Michigan Basins and one in the uplifted Cincinnati Arch region. All three field projects were conducted in a series of steps that contribute towards development of best practices for carbon capture and storage (CCS) validation that are applicable to the MRCSP region and elsewhere. Although specific practices are highly site dependent, the general steps include initial regional geologic assessment, site characterization through seismic surveys and drilling of test wells, permitting, outreach, development of a CO 2 supply system, injection and monitoring operations, and post-injection monitoring and site closure. Collectively, the regional mapping and three field demonstrations provide significant insight into geologic storage feasibility over a range of rock types and properties. Two of the tested sites indicate injection and storage rates exceeding 1000 tonnes/day/well. Such rates suggest that commercial-scale applications should be possible with a reasonable number of wells. The regional mapping of these zones also indicates that the tested layers are likely to be continuous over a large area, and, therefore, have potential for large-scale, long-term injection operations required for the numerous CO 2 sources in the region.