This is a summary version of the Swedish Civil Contingencies Agency (MSB) report, If one goes down – do all go down?. The objective of the report is to present the agency’s Government assignment to identify and analyse critical dependencies in society and to distribute the results to the actors that have a need and an interest in studying them. Clear target groups comprise central authorities, county administrative boards and municipalities as well as private actors. Knowledge about dependencies is the first step towards stopping propagation effects that could lead to serious crises for society in a worst case scenario.