Safety, reliability and risk analysis and management are the keywords in engineering these days. Yet while technical solutions are in many respects extended by safety margins of 30 to 70% commercial risks are limited to surcharges of the order of 1% forced by the actual market situation. In this respect a proper and sensible management of risk is the key to handle constructional and mechanical questions as well as operational challenges. The presented approach implies modeling the development of knowledge regarding a specific risk, based on both the physical manifestation and the awareness of risk and a representation of the actual project by some explicit parameters like complexity, connectivity and sensibility. Based on these elements the unknown and unforeseeable consequences of a risk given only by probabilities but in case of occurrence ruling out every schedule can be replaced by well defined measures. We expect such an approach of controllability to provide alternative means to handle risks both on constructional as well as on operative tasks even if statistical methods fail. The remaining risk is well defined while the actual hazard is compensated by measures which generate costs but can be kept within affordable and calculable limits.