The Southeast Offshore Storage Resource Assessment (SOSRA) project is assessing prospective geologic storage resources for carbon dioxide (CO2) in State and Federal waters of the Mid-Atlantic, South Atlantic, and the eastern Gulf of Mexico (Figure 1). The project is defining the size and geology of the prospective storage resources (including areal extent, thickness, and physical properties such as porosity and permeability) using existing geologic and geophysical data such as seismic reflection surveys, geophysical well logs, and supporting reservoir data (pressure, temperature, etc.). A diverse suite of data analysis techniques is being used to ensure that a high quality assessment is performed to meet the goal of predicting storage capacity to within 30 percent. The analysis started with a survey of available knowledge to provide an overview the basic geologic framework of the project regions, identify potential storage units in those regions, and define the key planning areas. The initial phase of work concludes with a comprehensive analysis of available data that includes a quality and coverage assessment. The second phase of work continues characterization of offshore CO2 storage opportunities, performs a volumetric CO2storage assessment, contributes to the development of best practice manuals and identifies economic and technical barriers that must be addressed or avoided to ensure timely deployment.