The aim of this article is to provide a comprehensive overview of the problem of vacant land in the La Plata Party, by introducing analytical variables that take account of the characteristics of the urban expansion process in the peripheries of the city. The methodology adopted identifies the vacant land in the study case, to be analysed according to two variables: the intensities and forms of occupation of the dominant territory, and the legal framework governing the potential future use of that land. On the basis of this analysis, the results obtained summarise relevant aspects of the current process of expansion of urban peripheries, identifying the characteristics of the growth axis in which they are located, in relation to land take and vacant interstitial land.