The UN Conference of the Parties to the Convention on Climate Change (‘COP’) has been getting steadily bigger over its almost 30-year history. Does size matter in the climate agenda, and how does the format of the conference further, or limit, its goal of international cooperation? This article considers the impact of expansion, and what it means for food systems. Ruth attended COP28 as part of a role with another organisation, Sri Lanka-based think tank SLYCAN Trust. She also attended the 2022 COP27 in Sharm el-Sheikh as an employee of the Scottish Government.