Climate change has already had severe impacts on the world’s oceans; moreover, threats such as rising water temperatures and ocean acidification seem set to increase. Effective regulatory responses are urgently needed to mitigate these adverse effects – or at least to adapt. And yet, ‘ntil recently, climate change was seen as an “over the horizon” challenge for the law of the sea’, as Tim Stephens has pointed out, criticizing responses thus far as a ‘wait and see approach’. Against this background, the contributions to this volume have assessed how the Law of the Sea Regime can be interpreted, applied and where necessary developed to support the objectives of the UN Climate Regime.