This paper examines the transformation of the radical left in Southern Europe since the transition to democracy. Once thought to be doomed to extinction, Radical Left Parties (RLPs) in Greece, Portugal and Spain not only managed to overcome the electoral decline of Communism but have also become key political actors in the aftermath of the Great Recession. What explains the rebirth of RLPs in Southern Europe? We argue that this is explained by two factors: political innovation and a favourable context. Political innovation models have differed across countries, but the result has been the emergence of a fragmented radical left with new left movements capable of reaching beyond the traditional electoral constituencies of communist parties by emphasizing positions on both economic and non-economic issue dimensions. This, in turn, has allowed RLPs to benefit from favourable political and economic contexts by allowing them to compete more effectively with the mainstream left.