In this article, Anwen Elias and Ludger Mees examines the shifting territorial goals of two of the most electorally successful and politically relevant nationalist parties in Spain: the Partido NacionalistaVasco (PNV) and Convergència i Unió (CiU). Whilst both parties have often co-operated to challenge the authority of the Spanish state, their territorial goals have varied over time and from party to party. We map these changes and identify key drivers of territorial preferences; these include party ideology, the impact of the financial crisis, the territorial structure of the state, party competition, public opinion, government versus opposition, the impact of multi-level politics and the particularities of party organisation. These factors interact to shape what nationalist parties say and do on core territorial issues, and contribute to their oscillation between territorial accommodation and secession. However, the way in which these factors play out is highly context-specific, and this accounts for the different territorial preferences of the PNV and CiU. These findings advance our understanding of persistent territorial tensions in Spain, and provide broader theoretical insights into the internal and external dynamics that determine the territorial positioning of stateless nationalist and regionalist parties in plurinational states. See full article, here.