Transnational advocacy networks (TANs) are among the most salient new actors in international politics and an important part of a novel and growing research agenda focusing on issues of transnationalism and global governance. Despite the increasing attention social scientists have devoted to the study of transnationalism and TANs, there have been relatively few comparative studies of TANs. Moreover, different aspects of TANs have been studied in different subfields of political science, and there have been few attempts to integrate the sub-disciplinary perspectives.What is needed, therefore, are more comparative and theoretically grounded studies that integrate the theoretical and empirical insights of the relevant literatures in international relations and comparative politics. Arguing that research on TANs can be fruitfully grounded in the theoretical literatures on social movements and international regimes, this paper draws on the theoretical lenses developed by these literatures to compare three TANs: The International Campaign to Ban Landmines, the Kimberley Process and the International Action Network on Small Arms. These three TANs have had varying degrees of success, and the paper explores two related questions: What are the dynamics and processes that underlie and explain their success or the lack thereof? How and under what circumstances do transnational advocacy networks contribute to global governance? Using data gathered in interviews with NGO staff and activists involved with these TANs, the paper finds that a combination of concepts and variables advanced by these two bodies of literature to explain the emergence/outcomes of social movements/international regimes can explain when and how TANs can be successful in introducing new instruments of global governance. ..PAT.-Conference Proceeding [ABSTRACT FROM AUTHOR]