Book excerpt: International Organization in Time investigates the effects of reform programs on international organizations (IOs). Drawing on insights from historical institutionalism and sociological organization theory, the book develops a theory of IO fragmentation to account for the centrifugal tendencies of the global polity. Focusing on the reform problems in the United Nations system in general and the World Health Organization in particular, the findings of International Organization in Time not only advance scholarly understanding of institutional development beyond the state, but also raise important questions about the legitimacy of international organizations.