editorial reviewed ; To study a drought which is a complex hazard with multiple and cumulative impacts depending on environmental and societal context, it is essential to understand the course of key events of the crisis and interactions between them. A better knowledge of the dynamics of this risk can improve the management of future crises by correcting identified past failures. In order to achieve these objectives, we used an original and innovative tool: the chrono-systemic timeline. This consists in a transversal analysis instrument that allows visualization – in a single diagram – of temporal and multi-sectoral highlights of crisis and their relationships. The chrono-systemic timeline is particularly adapted to a holistic analysis of water scarcity. The successive droughts of 2018, 2019 and 2020 in Wallonia (Belgium) served as a case study for development of this tool. The data introduced into the model concern environmental conditions (climate, hydrology), economic and social context (water production, agriculture, natural environments, energy, navigation, tourism, public health) and political and administrative decisions. The study shows presence of water stress situations in all socio-ecosystems of the territory with a reactive crisis management and concludes that it is necessary to better consider drought risk in public policies and to put in place anticipatory and adaptive management of this risk. ; 13. Climate action