The project proposes a complete analysis of the use of 2.0 tools in an emergency situation - mode, content, tone and temporality - as well as the changes that these new uses generate in communicative management and its impact on the population. For the study, three very recent emergency periods have been selected that allow us to make a detailed x-ray of the current use of new technologies in emergency communication: the Germanwings flight accident (March 24, 2015), the contagion by Ebola of the nursing assistant Teresa Romero (October 6, 2014) and the accidental chemical leak in the town of Igualada, Barcelona (February 13, 2015). Based on a mixed quantitative and qualitative analysis, it is proposed to analyze the use of the 2.0 communication tools that the actors involved did in communicative management, with special attention to leadership in information, transmission, interaction with the user, discourse and repercussion in the network.