“…As laid out in this introduction, this 'politics turn' is accompanied by an increased interest in research on political behavior of individual and collective actors in the EU multi-level system The various contributions in this thematic issue link research on party organization (Pittoors, 2020), electoral behavior (Braun & Tausendpfund, 2020;Schmitt, Sanz, Braun, & Teperoglou, 2020), interest groups (Berkhout, Hanegraaff, & Statch, 2020), party competition (Lefkofridi, 2020), responsiveness (Lefkofridi & Giger, 2020) as well as government politics and parliamentary behavior (Euchner & Frech, 2020;Heinkelmann-Wild, Kriegmair, & Rittberger, 2020) more broadly to the multi-layered systems within EU Member States, but also between EU Member States (Koß & Séville, 2020). Although the "European polity is a complex multi-level institutional configuration, which cannot be adequately represented by theoretical models that are generally used in international relations or comparative politics" (Scharpf, 2010, p. 75), the conceptual, theoretical, and empirical insights gained in this thematic issue shed light on various aspects of political behavior in the EU multi-level system beyond the predominant focus on electoral politics across multiple levels of government (see, e.g., Golder, Lago, Blais, Gidengil, & Gschwend, 2017).…”