The methodology proposed in this manual enables the study of two important types of interdependencies between essential infrastructures: physical and geographical. It involves defining a study area and analyzing the customer-supplier relationships between critical infrastructures and the temporal and spatial consequences of the unavailability of a given resource. These consequences are presented as curves, which depict the propagation of domino effects over time in the study area. The methodology also permits an analysis of how critical infrastructures will fail and enables the identification of infrastructures vulnerable to these failures. Overlaying these layers of information allows areas that are most sensitive to geographical interdependencies to be identified and mitigation measures to be implemented.