This book examines how International Organizations (IOs) govern migration on the ground. Contributing primarily to the scholarly field of international relations, it addresses an angle that has so far been overlooked—namely, the de facto governance of migration. Focusing on a time of crisis in governance, or the so-called European migration crisis of 2015 and 2016, this book shows that laws, rules, and policies on paper are simply insufficient for the management of migration in practice. Instead, it is through improvised solutions, and daily negotiations and routines, that field staff address daily challenges, while headquarters staff consolidate and diffuse this situated knowledge across contexts. Accounting for the interactions between IO actors at different analytical levels, Kortendiek advances a theoretical framework that helps explain migration governance as it is.

In doing so, the author makes a series of highly valuable contributions to the literature. Perhaps the most important of these is the book’s ambitious but successful attempt to move the discussion beyond what IOs could or should be doing to govern migration and describe and explain how they carry out policy in practice, through the ad hoc responses and discretionary decisions of fieldworkers on the ground. The book thereby focuses our attention on those who help migrants as part of their daily working routine, despite the pressing, uncertain, and unfavorable conditions in which they find themselves. These conditions include the limitations, gaps, and constraints of the existing policy frameworks, as well as the persisting shortage—or mismanagement—of human and material resources. A profound observation the author makes here is that fieldworkers not only shape policy outcomes and, therefore, directly affect the lives of migrants but also ultimately shape the policy itself.

Another major contribution of this book comes from its focus on an issue that is deeply contested and politicized, migration, and a point in time when there is a crisis in governance. This means that the existing weaknesses of the global migration governance system (described as the “missing regime,” p. 84) have been further exposed while the need for immediate and effective solutions is ever more acute. The observations made and the lessons learned from scrutinizing this issue at this specific time in history can therefore be applicable and prove helpful in other similar situations in the future. Moreover, the insights this study has yielded are both theoretically and practically relevant. Based largely on the author’s ethnographic observations at an important European border, the book’s key messages not only inform the theoretical debates on the role of IOs in migration governance but also have significant policy implications.

Among the main strengths of this book is the clarity with which the ideas presented are organized and formulated. The structure of the book and its individual chapters is simple, logical, and intuitive, helping the reader navigate with ease the various strands of the author’s argument. Throughout the book, the author does very well in explaining complex ideas and concepts in plain language. This is the case for the book’s proposed theoretical framework, the interplay between “situated learning” and “stabilization.” It is also true for existing grey areas in migration management, such as the treatment of mixed migration as a single analytical category, or the intricate and conflictual dynamics of today’s global migration governance architecture. Additionally, as this book is partly based on original data collected by the author through participant observation, it offers a rich array of vivid vignettes that illustrate the challenging situations and the daily interactions taking place on the ground. It thereby offers an engaging narrative and assists readers in developing an in-depth understanding of the case in point.

While this is not a significant limitation, a criticism could be made regarding the book’s narrow empirical focus on the Greek island of Chios, and the question that follows concerning the degree to which the observations from this case study can be generalizable in other contexts. The harsh and chaotic conditions experienced by migrants stranded on the Greek islands during 2016–2017 have been characterized as unprecedented, at least on European soil. This could mean that the book’s key observations (e.g., regarding the high degree of discretion among fieldworkers or the prominence of ad hoc solutions) may not be automatically extrapolated to other cases and geographic regions.

The book could also have been further strengthened through the inclusion of a brief discussion on other strategies of global migration governance, specifically those that go beyond the situation at the borders. Such strategies include the externalization of migration management, for instance, through European Union (EU) agreements with third countries. While these are, in principle, separate from border control mechanisms, they very much influence one another, as we see in the impact of the EU-Turkey agreement on the conditions in the refugee camps at the Greece-Turkey border, which this book does discuss.

Overall, this book presents an informative, convincing, and welcome addition to the existing literature. By connecting ground-level dynamics with macro-level processes and doing so through both the introduction of innovative theoretical tools (“the loop model of governance,” p. 32) and the use of illustrative empirical data, Kortendiek makes a commendable contribution to the study of migration governance. Shedding light on the surprising power of fieldworkers seeking and finding solutions on the ground and situating this alongside international-level tensions and power dynamics, this book offers a unique and realistic synthesis of the de facto governance of migration and the role of IOs in it. The insights we gain from this book may inform multiple scholarly fields within and across political science, international relations, and migration studies. Written in a clear and accessible manner, this book would be of interest to scholars, policymakers, and the wider public alike.