The paper presents an approach for studying the invention and the construction processes of new institutions and norms that is based on the methodology of Conceptual History. It is argued that the building of the EU as a polity was decisively shaped by political conflicts that centered on controversial interpretations of key concepts such as democracy, parliament, or citizenship, and that these conceptual controversies are particularly fruitful objects of analysis, as they relate to both the realms of political theory and institutional practice, and moreover to both the functionality and normativity of new norms and institutions. Concepts are to be regarded as socially constructed factors and indicators (Koselleck) of the reality they describe, interpret and modify. Conceptual controversies, then, are nodal points of key controversies, conflicts, and changes under way in the material, social and political reality. The approach presented hence allows to focus specifically on the nexus between speech acts and political practices that aim at constructing new norms and institutions, the respective meanings and normative connotations that are constructed, the institutional reality that is shaped in the end, and the interrelations between academia and politics in these processes. The paper presents the theoretical and methodological premises, as well as exemplary heuristic and analytical tools of the approach, and it discusses differences, similarities and added value as compared to discourse analytical and practice theoretical approaches.