This book explains how transnational policy entrepreneurs have contributed to the transfer of the contested concept of 'Policy Coherence for Sustainable Development' (PCSD) in global policy. Tracing the processes by which the PCSD concept has been diffused in an international epistemic community linked to the EU and the OECD, the book offers new insights on international public administrations' influence on global decision-making. It highlights the dynamic and multi-directional character of knowledge circulation in policy transfer. Drawing on case studies from France, the United Kingdom and Germany, the book contributes to current debates on sustainable development, revealing the role of actors and the logics behind 'policy coherence'. Thus, it allows to understand the challenges involved in implementing SDG 17. Given its scope, the book will be of considerable interest to academic audiences and students of international relations and policy analysis, as well as practitioners and public officials whose work involves global sustainability policy.