This book offers a detailed analysis of affective polarisation based primarily on a unique dataset created from an online panel survey in Spain. Spain is a country that provides a rich context for the exploration of identity-based polarisation. The analysis spans particularly politically relevant times in Spain during which identities were highly politicised, providing important lessons for the comparative standpoint. A series of different individual-level measures of likes and dislikes towards different social-groups, including partisan supporters, national and subnational identifiers and other social groups are provided in the survey, allowing the authors to observe the social identities behind the growing levels of individual affective polarisation. Contributions in this volume examine the time trends of affective polarisation over this period of intense political instability and crisis and evaluate the potential factors that might explain its dynamics. The book pays special attention, on the one hand, to the party supply effect and, on the other, to the increasing partisan and ideological content of press and social media. It also looks at some potential behavioural consequences of affective polarisation such as the change and dynamics of party system, turnout, and support for radical right-wing parties (RRPs). Affective Polarisation in Spain: Electoral, Regional and Media Conflictuality will be beneficial for students, researchers and scholars of Spanish History and Politics, Sociology, and International Relations. The chapters in this book were originally published as a special issue of South European Society and Politics.