In this book, Rebecca Adler-Nissen seeks to lay the foundations of a political sociology of European integration. She does so by examining the diplomatic practices surrounding “opt-outs” in the European Union—decisions on the part of individual member states not to participate, like everyone else, in an area of European cooperation. Focusing on the ways in which national representatives manage their country’s opt-out in day-to-day diplomacy, on the one hand, and on how opt-outs are perceived by their cooperating partners, on the other hand, promises to offer a unique perspective on the EU as a political project. More important, opt-outs serve as a prism for understanding the transformation of sovereignty itself (p. 9).

The book’s argument is intriguing. Instead of leading to a marginalization of certain member states and contributing to European disintegration, as many politicians and scholars claim, opt-outs may in fact reinforce the integration process. Drawing on the work of Pierre Bourdieu and Erving Goffman, Adler-Nissen argues that the EU is a transnational field, in which European diplomats share a common “doxa”—an undisputed premise of European integration as a process toward ever closer union (pp. 57–58). In this environment, opt-outs carry a stigma that raise questions about the degree of solidarity between the member states and the political, legal, social, and philosophical limits of European integration. It is interesting to note that countries cope with stigmatization in different ways. Some reject it and turn the stigma into a kind of proud emblem, while other countries accept the stigma and try to whitewash it through good behavior (p. 69). These coping strategies, Adler-Nissen argues, show that opt-outs are not simply an assertion of sovereignty. They reveal that the EU and the very meaning of sovereignty are partially created through the stigmatization of transgressive states (p. 3).

One has to appreciate, first, the novelty of this research. Most work on the subject focuses on the decision to eschew further integration. Few ask, however, how opt-outs impact the episteme and practice of the EU’s diplomatic community. Especially interesting in that regard is the discussion in the conclusion about the limits and, in fact, fragility of the doxa in times of crisis. One admires, second, the depth of empirical research. Rejecting a formalistic understanding of the EU, the author rightly argues that the study of practices is the key to understanding institutions. Hers is an empirically informed approach to European integration, which begins by looking at the face-to-face interactions between individuals and groups who negotiate on behalf of their states or institutions. The two case studies on the British and Danish opt-outs from the euro and on the cooperation in asylum, migration, and civil law are based on more than a hundred interviews and the author’s own practical experience. One welcomes, finally, the author’s boldness. The debate about sovereignty in the EU is one of the most researched and sophisticated in the social sciences. Few endeavor to contribute an entirely new perspective. In that respect, Adler-Nissen’s gutsy approach is most refreshing and engaging.

There is, however, some reason for skepticism. Although the argument about the integration doxa and the stigmatization of opt-outs is intuitive, one is left wondering why and to what extent it matters for our understanding of the EU and state sovereignty more generally.

First, the precise contribution of the work is less clear than it seems. The author claims that in contrast to existing research, her research reveals that the management of opt-outs reflects a retreat from national sovereignty rather than an expression of it (p. 3). These findings, she asserts, cast doubt on legal analyses of the EU as a collection of formal rules. Moreover, the fundamentally different view of state sovereignty questions various bodies of political science scholarship on, for example, interest formation, power, influence and cooperation in the EU.

Yet despite its prominence in the subtitle and an entire chapter on “late sovereign diplomacy,” the concept of “sovereignty” itself, and how it relates to the various political science concepts that the author wishes to challenge, remains elusive. The argument that autonomy qua legal sovereignty is a chimera or, as the author expresses it, “sovereignty claims cannot be solely understood on the basis of formal rules” (p. 15), should not come as a surprise to social scientists. The more important question is what this actually means for the state, modern cooperation, and the EU itself. The book brilliantly shows that EU diplomats struggle with these questions as well, but it is less successful in answering them. Ultimately, the impression is left that in its attempt to overhaul our understanding of the EU as a whole, the book loses sight of what might have been its most significant contribution.

Second, the book would have benefited from a more direct engagement of potential alternative narratives. To be sure, the argument about the existence of an integration doxa among EU diplomats is intriguing. But given that such undisputed premises are difficult to uncover empirically, one wonders if this is in fact the only or even the most relevant doxa among EU diplomats. Studies of the EU Council by scholars such as Robert Thomson, Bernard Steunenberg, many others, and myself have pointed to the existence of a norm among EU officials that says that important state interests should be accommodated. What one might call the “sovereignty doxa” results in various informal practices, such as the practice of consensus decision making, which makes majority voting a true exception in the council. In this narrative it is integration that needs to be managed within the context of a sovereignty doxa, not the other way round. The stigma consequently lies with those that push integration to a point that it violates a government’s legitimate interests—arguably something that we currently observe in the management of the Eurozone crisis. The point is not that the book does not convince. The point is that a more direct engagement of alternative views would have made it more convincing.

Finally, Opting Out of the European Union raises many interesting questions that one only hopes the author will answer in a sequel. The case studies, for example, reveal that some members and especially the Commission are quicker than others in stigmatizing those that opt out. Is the doxa, therefore, unevenly shared among EU officials? Is the stigmatization of outsiders a deliberate strategy of some, and for others a genuine emotional reaction? Additionally, what explains that the UK and Denmark handle their stigmas so differently? The author suggests that this has something to do with the countries’ history and size (pp. 11–13). But the fact that there is also variation across the two policy areas suggests that perhaps more idiosyncratic reasons are at play. Finally, at what point does a doxa turn from a taken-for-granted premise into a contested ideology? This question is given much thought on the final pages. But in light of the debate about a British exit and the ongoing Eurozone crisis, which pose an unprecedented challenge to the “ever closer union” narrative, this question will only gain in importance. Politicians, citizens, and EU scholarship alike have yet to address it.