CO2 emissions from international shipping, which are currently unregulated, are predicted to rise dramatically if no regulations are implemented. International bunker fuel emissions have been excluded from the Kyoto Protocol; the UNFCCC conference in Copenhagen also failed to bring about clear directions on how to proceed with these emissions. In this paper, the various options suggested by the Subsidiary Body for Scientific and Technological Advice of the UNFCCC for allocating CO2 emissions from international shipping to individual countries are investigated. This is followed by a discussion of the economic and regulatory issues related to these options and the consequences of applying them. Then, the various options are evaluated on the basis of environmental effectiveness, possibility of legal implementation, and fairness of burden sharing. The evaluation shows that there is no single allocation option that can be regarded as environmentally effective, legally effective and allowing for fair burden sharing. Nevertheless, it is concluded that an allocation of international shipping emissions should be conducted on the basis of the operating company.