The paper deals with rockfall phenomena and, in particularly, with the design of protection works aimed at mitigating the associated risks. The study is aimed to analyze all phases involved in these complex processes, including the triggering phase, the propagation phase, and the impact with structure designed to stop or reduce block motion and protect vulnerable objects. The paper analyzes each phase, illustrating the state of the art and ongoing developments in the field. Although flexible barriers (a type of structure specifically analyzed in the paper) are widely utilized in mountain areas, a design procedure that allows for dimensioning the structure with a given probability of failure is not available yet. The paper discusses the complete design process, outlining the potential of new technologies applied to the design of flexible barriers, considering a holistic design scenario.