Public conservation policies in Catalonia began in the 1970s as a response to a demand from civil society, with a growing concern about the negative impacts of Franco’s developmentalism, and were configured as an instrument of land-use planning. Based on qualitative interviews with informants of different profiles who played a special role in this period, this article studies the institutionalisation of nature conservation in Catalonia between 1970 and 1988, analyses the role of the administrations involved, and shows the relevance of the changing political-social context of the period in this process.