Dangerous phenomena threaten human settlements and infrastructures in many sectors of the Earth. Specific actions are required for proper risk management, starting from hazard identification to risk mitigation (including monitoring and early warning) and reduction. Aiming at evaluating risk conditions, the set of causal factors must first be identified; then, the evolution (in space and time) of a given phenomenon must be predicted, e.g. using modelling approaches. Potential damage should be assessed by considering the vulnerability of the elements at risk, including its expected variation in terms of social, environmental, and structural components. Total risk evaluations should provide supporting information for optimal selections of mitigation and/or reduction measures, based on expected impact scenarios.Precious lessons inferred from past disasters can be combined with adequate planning of human settlements, thus minimizing future risks. Unfortunately, the zero risk option is often unrealistic but innovative approaches can be adopted to minimize the residual risks. These include integrated modelling and monitoring of hazardous phenomena, vulnerability evaluations and land use planning, knowledge dissemination and risk communication, and adoption of remedial measures. If an area is threatened by different types of phenomenon, the evaluation of the overall risk may become quite complex.Several approaches for risk evaluation have been proposed in the past decades (Iovine 2013): on one side, qualitative and quantitative techniques have been tested against real case studies, at local or regional scales; on the other, modelling and sensitivity analyses have been employed, and real-time monitoring systems implemented to support early G. Iovine