This article starts from the consideration of the concept of ‘social space’ as a constructive, comprehensive and interpretative key to Henri Lefebvre’s work as a whole. Therefore, the genealogy of the lefebvrian project of ‘spatiology’ (or analysis of the social production of the social space) and its importance for contemporary critical thinking are set out. At the same time, the plans for the criticism of the political economy by Marx are clear in the lefebvrian question for social space and, consequently, the question of the historical challenge posed by the capitalist domination of space and the possibilities for its emancipation. Finally, the scope of the nodal definition of the lefebvrian concept of social space is characterised: the ‘reproduction of social relationships of production’. Noteworthy ideas: a reflection article presenting advances in doctoral research on the concept of social space, by Henri Lefebvre, and the Lefebvrian project of a ‘spatiology’ or analysis of the social space and its production.