Carbon dioxide capture and storage (CCS) technologies are increasingly recognised for their capacity to provide a large contribution to the mitigation of greenhouse gas emissions in the coming decades. This paper assesses the policy questions as highlighted in the relevant COP/MOP 2 decision, particularly leaks and permanence for geological storage, project boundaries and liability issues, and leakage, as well as a few others raised by some parties. Since any emissions or leaks during the separation, capture and transport phases would occur during the crediting period of the project, the paper focuses its analyses for leaks and liability on storage, as it is in this part of the CCS process that long-term leaks could occur.