There has been a growing interest among scholars in analysing the phenomenon of niche parties, as actors that bring new issues into established arenas of party competition. Parties that advocate the defence of ''national'' interests and the territorial re-organisation of the state - referred to here as autonomist parties - have often been included in the niche category. This literature has provided innovative insights into some of the ways in which autonomist parties impact upon established patterns of arty competition. However, this paper argues that there are also several limitations to such an approach. Not only are autonomist parties more mainstream than niche actors in many places, but the current literature also ignores how autonomist parties themselves make strategic decisions about how to compete with established rivals, and how they are affected by the strategies of these rivals. This paper aims to address these shortcomings by providing a new framework for analysing party competition in arenas where there is a strong territorial dimension. It takes as its starting point the work of Bonnie Meguid on the competition between niche and mainstream parties, and develops this to better account for the realities of party competition in multi-dimensional arenas, and where regional politics are usually nested within the broader context of state-wide politics. The framework will be applied to an analysis of party competition in two different contexts: Catalonia and Wales. The findings will serve as a first step towards towards developing a more comprehensive understanding of the role of territory in party competition.
