Most studies of the EU and its member-states are concerned with how processes of European integration hit the member-states. This article shifts emphasis from this top-down towards a bottom-up approach and asks whether and how differences in domestic institutional constellations shape the representational roles of member-state officials when carrying out representational tasks in the EU Council of Ministers. The key objective of this study is to build a conceptual framework that renders intelligible the domestic origins of representational roles among domestic officials attending EU institutions. For this we draw on theories of political representation, institutional theories and the literature on how member-states adapt to European integration. Our primary argument is that role perceptions are considerably conditioned by actors domestic institutional embeddedness. This argument is substantiated by an illustrative comparison of Belgian and Swedish officials attending working groups within the Council of Ministers.