We examine why patronage may constitute an important dimension of analysis in the study of Portuguese political parties and the evolution of its party system. In particular, we are interested in exploring two inter-related aspects: first, what is the role of patronage for party organisations in Portugal? And second, how does it impact on intra-party functioning? Overall, access to state resources appears to be crucial in the rapid building of the party organisations and in their subsequent maintenance, potentially creating also barriers to entry for new competitors. This pattern is to a large extent explained by the context in which parties emerged in Portugal, which substantially shaped their organisational structure and societal roots.