The case of European offshore carbon dioxide sequestration informs us that the international and European environmental liability frameworks for the protection of the marine environment are developed but several issues remain to be addressed and that they are still not completely ready to accommodate this technology. A detailed look is taken at the status of offshore CCS under public international law: the United Nations Convention on the Law of the Sea, the London Convention, the London Protocol, and the OSPAR Convention. Subsequently, European law is analysed, the CCS Directive and the Environmental Liability Directive in particular. Finally, the liability related to carbon dioxide transport by pipelines is examined.