This chapter focuses on the regulatory environment for geological sequestration of CO2. Large-scale geological sequestration of carbon dioxide (GS) poses a novel set of challenges for regulators. It explains the unique needs of large-scale GS projects in light of the existing regulatory regimes in the United States and Canada and identifies several different approaches that might be considered. It also discusses some crucial elements that must be addressed in any regulatory regime for large-scale GS and outline different types of approaches that might be considered. Whether the regulatory regime is primarily performance-based or procedural will have important consequences for the evolution of the regulatory structure and the technology itself. U.S. and Canadian regulatory structures are compared for managing underground injection; identify specific areas in the existing Canadian and U.S. regulatory environments that might need to be adapted to provide more effective management of GS; and, suggest the tradeoffs of different types of regulatory changes for managing large-scale geological sequestration projects.