A common feature of contemporary domestic and transnational political systems is the extensive and ever-growing participation of interest groups in the policy-making process.1 While this observation is widely documented, the consequences of these developments, especially the consequences of opening up international organizations (IOs) to the input of interest groups, are often still poorly understood.2 Many proponents argue that opening up to the input of interest groups will result in more proficiency, accountability, and legitimacy. Opponents contend that the inherently biased nature of interest representation could lead more open IOs to capture by special interest groups.
In this article I analyze how and why the interest group communities that lobby during UN climate summits evolved over the past two decades.3 I explicitly link the analysis to the broader literature on interest group community development, which generally focuses on domestic political systems. I also connect two literatures that have...