This thesis explores how the legislative roles of individual Members of Parliament (MPs), parliamentary committees and parties change as policy making authority is successively transferred to the European Union (EU). My argument is that the legal activities of the EU cause a segmentation of the legislative role of national parliamentary actors across policy fields as well as of the contemporary conditions for parliamentary democracy. I test this argument on the case of the Swedish Riksdag as this parliament is usually believed to have responded particularly well to the integration forces. The empirical analysis proceeds in cumulative steps. The first step is a quantitative and longitudinal analysis of the policy making context that the parliament finds itself in. It is shown that policy issues are Europeanized to decidedly different degrees and, such differences across policy areas increase over time. Regarding legislative parties’ election manifestos instead, a very different pattern emerges. Parties connect the European legislative arena in their policy pledges only very selectively. The second step of the analysis draws on interviews with MPs and parliamentary high officials in the two committees of agriculture and culture as between them they showcase the largest difference in terms of Europeanization. MPs in the Committee on culture cherish their independence from Europe and their task in parliament depends principally on whether they enjoy the majority position or not. In the Committee on Environment and Agriculture, by contrast, MPs are well aware of the limitations EU legislative authority imposes on their and the government’s policy manoeuvrability and they describe their function in parliament as reviewing legislation rather than shaping public policy. The comparative findings point in the direction of an uncomfortable asymmetry between legislative output and input when it comes to the extent these agendas have become Europeanized. The twist to this is that while MPs at the individual level have come to terms with their new legislative role in agricultural policy making, at the party level they fail tremendously at transmitting this experience in the electoral arena. What Swedish parties engage in in the electoral arena is instead better understood as confused contestation: they continue to propose and debate policy measures that are decided in a different legislative arena than their own. This practice obscures the new ways in which policy making is conducted in the EU multi-level system and it has also upsetting consequences for transparency and accountability.