In this article, Byrne explores the likelihood that responsibility for climate change damage will become a criminal offence internationally. He argues that the focus should be on state responsibility and outlines the difficulties that such a proposal will face. Byrne explores several possible approaches that could theoretically modify existing international law to criminalize climate change damage but cautions that a more immediate action is needed. He suggests imposing greater international civil responsibility on polluter states, or alternatively, criminalizing only those environmental crimes most suitable for criminal sanctions. Byrne concludes that the two main obstacles to imposing criminal liability on states is that firstly, the damage has largely already been done, and that secondly, criminalization of climate change damage would require “an unprecedented level of global cooperation over an extended period.” Writing in 2010, Byrne proposes we should “encourage change, but not expect this to translate into legally enforceable rights and responsibilities any time soon.”