Carbon capture and storage could play an important role as a near-term bridging technology, enabling deep reductions from greenhouse gas emissions while still allowing use of inexpensive fossil fuels. However, filling this technological promise requires resolution of key regulatory and legal uncertainties surrounding both human and ecological health, integration within a larger climate policy, and clear assignment of responsibility and liability for long-term care. Deployment of CCS projects in the European Union (E.U.) and the United States (U.S.) may be technologically similar, but will be contextually different. In this paper, we explore the existing energy, policy, regulatory and legal climates that will necessitate different approaches for deployment. The high U.S. dependence on coal makes CCS very important if the U.S. is to achieve deep emissions reductions, while in the E.U. an established climate policy, the importance of off shore projects, and a supportive political climate are favorable to CCS deployment. Additionally, in Europe, regulators must clarify the classification of CO2 within E.U. and international regulations governing on and offshore projects, whereas in the U.S. subsurface property rights, abandoned wells, and state-level jurisdictional difference will play important roles.