The article focuses on the politicization of international authority as a thus far little understood development in world politics. We first define the concept and show that there is an empirical trend towards politicization of international institutions. We then argue that the increasing authority of international institutions has led to their politicization and we relate this hypothesis to alternative explanations. The validity of the authority–politicization nexus is illustrated by the rise of international authority in parallel to politicization. We go on to distinguish different policy functions such as rule definition, monitoring, interpretation, and enforcement in order to show that especially those international institutions with a high level of authority meet with strong contestation of their competencies. We conclude the article by exploring various avenues for future politicization research.

Following the failure of the Constitutional Treaty, executives of European Union (EU) Member States and the European Commission tried to take European integration as a political issue as much off the agenda as possible and limit involvement of citizens in EU decision‐making. This article assesses the viability of this attempt to combat politicization of European integration and comes to the conclusion that it is unlikely to succeed in the long run. Politicization, it is argued, is a direct consequence of the increasing authority of the EU. The executive response to reverse this trend, however, does not address its cause, but rather the intermediating factors in the form of political opportunity structure. Since the cause of politicization remains intact and intermediating factors are unlikely to be controlled by executives, this attempt to reverse politicization is not viable.

Whereas traditional institutions used to be seen as an international complement to a dominantly national paradigm, today's international institutions are an expression of political denationalization. The new international institutions are much more intrusive into national societies than the traditional ones. They increasingly contain supranational and transnational features and thus undermine the consensus principle of international cooperation. When society and political actors begin to comprehend this change, they begin to reflect on the features of a legitimate and effective political order beyond national borders. As a result, denationalization becomes reflexive and thus politicized. At the same time, the politicization of international politics harbours the potential for resistance to political denationalization, which increases the need – both from a normative and descriptive perspective – for the legitimation of such international institutions.

While legitimacy dynamics are paramount in global governance, they have been insufficiently recognized, conceptualized, and explained in standard accounts of international cooperation. This special issue aims to advance the empirical study of legitimacy and legitimation in global governance. It engages with the question of when, how, and why international organizations (IOs) gain, sustain, and lose legitimacy in world politics. In this introduction, we first conceptualize legitimacy as the belief that an IO's authority is appropriately exercised, and legitimation and delegitimation as processes of justification and contestation intended to shape such beliefs. We then discuss sources of variation in legitimation processes and legitimacy beliefs, with a particular focus on the authority, procedures, and performances of IOs. Finally, we describe the methods used to empirically study legitimacy and legitimation, preview the articles of the special issue, and chart next steps for this research agenda.

World politics is no longer a matter of executive multilateralism and technocratic expert decisions. What we see instead is the politicization of international institutions -a twofold process of growing resistance to and the more intensive utilization of these institutions. After providing evidence for this claim, this article develops propositions on the effects of politicization of world politics on the quality of decision making and the content of policies on both the international and national level. On the one hand, the politicization of international institutions arguably heralds a reflexive stage of global governance. The increased participation of societal actors leads to a new mode of decision making in world politics, which includes a notion of global common goods in conjunction with elements of public deliberation. By the same token, increased politicization of international institutions contradicts lamentations about the hollowingout of national democracies and shows that political participation is in fact partly emigrating to the international level. While politicization has the inherent potential for initiating the democratization of international institutions and making new types of global policies possible, there are on the other hand several dangers associated to this process. First, it may perpetuate existing inequalities between North and South in terms of representation on the global level. Second, the politicization of world politics puts pressure on national democracy, since it moves attention away from national political matters and skews national policies towards universalist positions. Moreover, it arguably provokes the constitution of a new political cleavage, cosmopolitanism vs. communitarianism, which may possibly restructure politics in the 21st century to a large extent. These propositions on the effects of politicization will be developed with the help of empirical illustrations. However, they will not be systematically tested -the purpose of this contribution is to elaborate the analytical potential of a new concept and identify broad trends.

While legitimacy dynamics are paramount in global governance, they have been insufficiently recognized, conceptualized, and explained in standard accounts of international cooperation. This special issue aims to advance the empirical study of legitimacy and legitimation in global governance. It engages with the question of when, how, and why international organizations (IOs) gain, sustain, and lose legitimacy in world politics. In this introduction, we first conceptualize legitimacy as the belief that an IO's authority is appropriately exercised, and legitimation and delegitimation as processes of justification and contestation intended to shape such beliefs. We then discuss sources of variation in legitimation processes and legitimacy beliefs, with a particular focus on the authority, procedures, and performances of IOs. Finally, we describe the methods used to empirically study legitimacy and legitimation, preview the articles of the special issue, and chart next steps for this research agenda.

The article surveys the literature on international `regimes'. Regimes are social institutions that influence the behavior of states and their subjects. They consist of informal and formalized principles and norms, as well as specific rules, procedures and programs. The term is explicitly broad and captures the unwritten understandings and relationships, as well as the formal legal agreements, that influence how states and individuals behave in any given issue area. Scholarship over the last decade has elaborated how regimes are formed; this article surveys that work and focuses on more recent scholarship that has turned from the formation of regimes to the question of what makes regimes in general `effective' and which `types of regimes' are especially effective. The survey concludes with the identification of future research priorities in the field.

Building on the empirical findings of the preceding articles, we advance three arguments+ First, while socialization research has typically been construed as constructivism's home turf, this volume's emphasis on mechanisms and scope conditions reveals that rational choice has much to contribute here as well+ We develop this claim by undertaking a "double interpretation" of each essay, which allows us to advance more fine-grained arguments connecting the two social theories+ Second, while there are good conceptual reasons for expecting a predominance of international socialization in Europe, the empirical cases instead suggest that its effects are often weak and secondary to dynamics at the national level+ We make sense of this puzzle by reasoning more explicitly in longitudinal terms, by drawing on work on European identity, and by noting that students of European socialization-as well as integration-have much to gain by "bringing the domestic back in+" Finally, while our collaborators have demonstrated the empirical and theoretical benefits of combining a social ontology with a positivist epistemology, this comes at a cost, with normative perspectives neglected+ This matters-and all the more so in a Europe marked by supranational constitution-and polity building+ Socialization dynamics may well take us beyond the nation-state, but their legitimacy and governance implications bring us back-forcefully-to it+ As a scientific term, the concept of socialization originated more than 100 years ago-in the first issue of the American Journal of Sociology+ 1 It later became a central term in sociology through the work of Durkheim, who saw it as the process through which individuals develop from the stage of being driven by instinct to being a sociable human being+ 2 Socialization research in general has, since then, been marked by a definitional paradox+ The closer the definition gets to the common-sense meaning of socialization-actors internalize norms and standards of behavior by acting in social structures-the more it runs into operational prob-We are grateful to the project participants and contributors to this volume for valuable discussions on the themes addressed here+ For detailed comments on earlier versions of this essay, we thank two anonymous reviewers, the IO editors, Peter Katzenstein, and Ron Mitchell+ 1+ Ross 1896+