This chapter applies Pragmatic Constructivism to interpret and assess two communities of practice: the Intergovernmental Panel on Climate Change (IPCC), which frames the problem of global warming, and the Conference of Parties (COP), which meets annually to discuss international society’s response within the UN Framework Convention on Climate Change (UNFCCC). Applying the book’s two normative tests – inclusive reflexivity and deliberative practical judgment – the chapter demonstrates how the IPCC maintains epistemic authority by appropriately managing the boundary that separates expert knowledge from non-expert opinion. The analysis of COP operates at a micro level (e.g. how physical space at the Conference is organized) and the macro level (e.g. whether it would be better to organize deliberations on a ‘minilateral’ basis). The chapter notes how this debate has been bypassed by the Paris Agreement and the decision to commit to Nationally Determined Contributions (NDCs) for emissions reduction. It assesses the consequences of that collective judgement in light of the progress made at the 2021 Glasgow COP. The chapter concludes that the problem should now be framed in terms of states delivering on the commitments they have made, and it considers the usefulness of nationalist dispositions and citizens assemblies in that process.