This chapter highlights that the framework for appreciating rights socialisation has become considerably more powerful over the last decade; it remains untested in the context of regional organisations, and pays scant regard to the significance of membership in shaping socialisation efforts. The chapter presents the substantive body of research that has investigated human rights socialisation, membership, and regional organisations, and the study of the expansion of the European Union (EU). The broader literature that considers regions, organisations, socialisation, and human rights offers tantalising clues about the diverse ways in which these fields can intersect, and the practice of different regional organisations around the world suggests many more political processes are occurring, with differing stories of success and failure. The older regional organisations outside Europe, such as the Organization of American States (OAS) or Association of Southeast Asian Nations (ASEAN), became more active.