You may not realize it, but natural hazards are ubiquitous. Earthquakes, tsunamis, volcanic eruptions, floods and landslides, but also hurricanes, intense rainfall, avalanches and droughts – to name the most common of them – are natural phenomena that occur since millions of years, contributing to sculpt the surface of the Earth where most of us live, work, travel and play. As for other continents, the attractiveness and the fascination of many European natural landscapes are the result of events, often catastrophic, that elevate hills and mountains (earthquakes), shape slopes (landslides, avalanches) and form plains and valley floors (floods). It should not be a surprise that these phenomena occur, as they result from physical laws that, even if not yet fully understood, do not escape the general laws that regulate the universe. We should instead ask ourselves why these natural events hit us so hard and so frequently. In Italy, one of the European countries more subject to natural hazards, the deaths and missing persons caused by earthquakes, volcanic eruptions, floods and landslides have been more than 10,000 since 1950; and the evacuees and homeless due to landslides and floods alone more than 750,000 in the same period. It is easy to see that a totally natural event becomes “catastrophic” when it interferes with the “human sphere” i.e., with the population, the cities and towns, the transport and communication networks, and with the private and collective properties and interests. If the interaction between natural hazards and the human sphere is somewhat inevitable, do we know how to cope with the consequences of the hazards? In the recent decades, our ability to respond to natural hazards has improved considerably. Today, in many European countries the rapid response to catastrophic events is very effective. Our ability to forecast hazards has also improved, although the capability to predict the consequences of the hazards is often less effective. Much less effective is our ability to manage the post-disaster reconstruction, a longer and more complex phase that involves economic, social and political considerations, in addition to scientific knowledge and technical and operational skills. There is a striking lack of a shared vision on how to deal with the long-term consequences of natural hazards, which imply huge investments and address complex phenomena that cannot be tackled with a mechanistic approach that breaks down the problem into individual elements, finds solutions for the single elements, and recomposes the solutions as one does to solve a puzzle. In order to enhance our understanding of natural hazards and to defend ourselves from their consequences, we need a new science, the “science of natural hazards”, capable of considering all the natural, environmental, economic, social and human elements that characterize the hazards and their consequences. In other terms, we need an integrated knowledge-based support to decisions which entangle the short-term response to emergencies and the long-term capacity to be resilient to changes.