The financial crisis that hit the Eurozone since 2008 has had a destabilising impact on the political systems of Southern Europe. Governments have been ousted from power, critical elections have questioned the bipolar structure of many party systems, and new political actors have challenged the traditional political game. While these events have been addressed in several works, less attention has been devoted to the survival strategies adopted by former incumbent parties turned opposition, such as the socialists in Spain and Portugal, in the period 2011-2015. These parties have faced multiple challenges: they lost government control, suffered dramatic decline in public support, struggled to defend their electoral base from new and old competitors. Despite an apparently high number of similarities, in both the political and the economic context, after one legislature in opposition, the PSOE and PS obtained different results at the 2015 elections and, above all, had to deal with very different post-electoral scenarios. The Paper intends to explore the reasons behind this outcome by focusing on two types of factors. First, the constraints faced by the two parties in the respective countries, since 2011 – notably, the impact of the economic recession, the level of trust in political institutions, the extent and type of social mobilisation and the competitive scenario. Second, the parties' internal context, in particular, the process of party leadership change and the spread of internal conflicts.
