Research and Analysis Conceptualising the Multi-Level Party: Two Complementary Approaches David S. Moon University of Sheffield Øivind Bratberg University of Oslo While party research has seen a number of conceptual developments in recent years, it has not kept pace with parties becoming more territorial as a result of the increasing importance of sub-national and supranational governance. This article lays down a framework for conceptualising and anal- ysing multi-level parties (MLPs). We propose a synthesis of the formal and non-formal aspects of power; the former highlighting party rules and procedures, the latter focusing upon the ideational structures – norms and competing ideologies/discourses – within which party members operate. For empirical research on the MLP we propose to focus on autonomy and influence to measure the extent of (formal and non-formal) multi-levelness and to grasp better the strategies of regional branches vis-à-vis the centre. Introduction This article sets out the contours of a revised approach to the analysis of political parties. Our purpose is to heighten awareness of the territorial dimension by establishing a viable framework for analysing multi-level parties (MLPs). The inter- play between different territorial levels is an increasingly prevalent feature of party politics. This is particularly evident in European Union (EU) member states going through parallel processes of regionalisation and European integration, such as Spain, Belgium and the UK, as well as established federations such as Germany and Austria. While an embryonic literature on MLPs has started to gestate, it has largely been constrained to what might be labelled the formal dimension of intra-party power relations – premised upon an analysis of rules, constitutions and positions (Hrbek, 2004; Poguntke et al., 2007; Swenden and Maddens, 2009b). Our aim is both to build upon and to move beyond existing approaches: first, by suggesting a clearer focus on certain formal features of power allocation in parties; and secondly, by including what might be labelled the non-formal dimension of intra-party power relations. The MLP could thus be defined as ‘a party of multiple territorial levels, representing competing sources of formal power as well as discur- sively structured antagonisms between the party’s centre and its constituent parts’. Acknowledging this latter aspect implies an analytical refocusing towards the effects POLITICS: 2010 VOL 30(1), 52–60 © 2010 The Authors. Journal compilation © 2010 Political Studies Association