Scholars are deeply involved in the process of European integration, but we lack systematic understanding of this involvement. On the one hand, scholars, academic ideas and ideologies shape European integration and policies (e.g. the Economic and Monetary Union and the free movement of people). On the other hand, EU institutions, policies and practitioners produce particular forms of knowledge (e.g. the Eurobarometer and benchmarking of national performances) that inform social scientific choices of theories, methods and research topics. Drawing on the new sociology of knowledge as well as Science and Technology Studies (STS) and political sociology, this introductory article develops a framework for studying the entanglement of EU studies with the EU around four analytical principles: (1) the principle of symmetry, (2) the principle of rejecting the internal/external division, (3) the principle of situatedness and (4) the principle of contextualism. A sociology of knowledge approach provides alternative explanations of the EU’s development and of our scholarly attempts to make sense of it.