Understanding the processes that lead to the introduction of national level climate mitigation legislation has acquired added significance due to the current impasse in international level governance. Greater policy learning and transfer at the national level could, to an extent, provide an answer to international apathy and inaction. In this respect, the UK Climate Change Act 2008 remains one of the few examples of legally enshrined national mitigation legislation and hence provides a critical, but surprisingly under-researched, source of learning for policymakers worldwide. In understanding the conditions leading to the introduction of the Act, this paper adopts an innovative theoretical approach based on combining Kingdon’s Streams Model with a more agency-based discursive perspective drawn from recent developments within new institutionalism. By employing this alternative approach to explain the evolution of the Act, this paper argues that a focus on discourse helps explain how entrepreneurial policy actors were able to, through their successive discursive interventions, construct the pre-conditions necessary for this particular policy window to emerge. By identifying the factors that facilitated the rapid and somewhat unexpected adoption of such ambitious climate legislation the paper then assesses the prospects for trans-national policy learning. One obvious lesson from the UK experience is that national policymakers should invest heavily in initially discursively constructing the case for climate legislation in order to secure a broad societal mandate for policy change.
