This chapter explores the analysis of Convention on Long-Range Transboundary Air Pollution (CLRTAP) in the wider empirical record of effective mobilization of usable knowledge. In CLRTAP, the European Monitoring and Evaluation Program (EMEP), the working groups, and the Network on Air Pollution and Health (AIRNET) all serve to identify research questions and guide science with some degree of autonomy from the political process. The chapter focuses on the development of sustainability science, which requires the substantial involvement of scientific expertise in policymaking. The maintenance and support of science bodies within multilateral environmental governance arrangements is absolutely vital for the construction of usable knowledge within the regime. William Clark and Giandomenico Majone defined the core ingredients to usable knowledge as adequacy, value, legitimacy, and effectiveness. The Intergovernmental Panel on Climate Change (IPCC) made it clear that it is harder to mobilize knowledge to address politicized and high stakes issues when knowledge is being developed as policy debates are occurring.