Although some technological risks can be traced back to the ancient times, it was between the nineteenth and the beginning of the twentieth century that technical advancement and the process of industrialization posed the question of the management of the technologies and of their possible disastrous consequences. During these years there was an important change in approaching these issues: from the inevitability of disasters to the adoption of policies of prevention and risk management. This important change had as a consequence an increasing role of public institutions (national governments, agencies and authorities) in the control, prevention and emergency management of technological disasters. According to this new approach, scientists, the experts and the technicians that were required to “predict” using their special knowledge technological disasters, became central figures. The first post-war period represents an important turning point because this new and modern attitude towards technological hazards reached its full maturity. The spreading of new technologies also facilitated by the process of industrialization and the emergence of the era of mass consumptions, influenced a new discipline that, from different approaches, tried to address and resolve the various aspects of technological threats. Born in the postwar period, the disastrology and in general policies to ensure safety, found a systematic application after the Second World War. The increasing complexity of certain technologies used in industry, in the production of energy, in the transport sector and especially the potentially catastrophic consequences of technological accidents, imposed an additional effort in the field of regulation, prevention and management of emergencies. In some cases, such as the atomic energy for civilian use, an increasing role was played by national and international agencies that were created during this period. Since the 1970s but especially in the following decade, several major accidents (Three Mile Island, Seveso, Bhopal, Chernobyl, Fukushima, the environmental disasters caused by oil tankers) put forward the need for a standardization of rules and a greater international co-operation. The globalization of technological hazards at the time of the so-called “risk society” has fostered a more interdisciplinary approach to the issues of technological disasters. Moreover, the increased number of new hazardous substances and materials and the opportunities for human error inherent their use has determined an escalation of technological accidents. All this factors and the more and more unstable boundaries between natural disasters and man-made disasters has necessarily imposed growing efforts for harmonization policies at a national and an international level to ensure collective security, public health and environmental protection.