The relationship between human rights and environmental protection in international law is far from simple or straightforward. A new attempt to codify and develop international law on this subject was initiated by the UNHRC in 2011. What can it say that is new or that develops the existing corpus of human rights law? Three obvious possibilities are explored in this article. First, procedural rights are the most important environmental addition to human rights law since the 1992 Rio Declaration on Environment and Development. Any attempt to codify the law on human rights and the environment would necessarily have to take this development into account. Secondly, a declaration or protocol could be an appropriate mechanism for articulating in some form the still controversial notion of a right to a decent environment. Thirdly, the difficult issue of extra-territorial application of existing human rights treaties to transboundary pollution and global climate change remains unresolved. The article concludes that the response of human rights law – if it is to have one – needs to be in global terms, treating the global environment and climate as the common concern of humanity.