A vast number of hazards can threaten infrastructural systems both due to accidental reasons and intentional attacks. While natural hazards to large socio–technical systems have been extensively studied, malicious threats –radically different due to their ability to develop apposite tactics– are less well known. Malicious attacks assessment and prevention has become an urgent concern, related to the development of proper strategies and tools for risk analysis and management. This project aims at developing a general framework for the comprehension of malicious hazards, in terms of the strategic offensive/defensive interactions among all the players involved, focusing on power systems. The project will provide a conceptual basis and with tools for assessing and managing malicious threats against power systems; and will also study the possibility of expanding the models to other infrastructures.