In this case study, Simon Wiegand examines the positions, influence strategies, and functions of the state government and parliamentary groups in North Rhine-Westphalia during the political process regarding the European energy and climate package during the CDU/FDP government from 2005 to 2010. Can the theses often represented in political science discussions about the loss of significance of the German states due to European integration and the de-parliamentarization of subnational politics be confirmed? This study addresses these and further questions while investigating the relationship between Europeanization and state politics. The Europeanization of energy and climate protection policy in North Rhine-Westphalia during the 14th legislative period did not lead to the exclusion of the state from the European multi-level system nor to the de-parliamentarization of subnational politics.