Systems security is of paramount importance. However, security levels and parameters are defined in a social context and are closely related to values, beliefs and interests. Security of systems is mainly related to people and society. Therefore, the focus of research in this area has to be on developing and testing practically applicable methods and tools to assure the security or IT systems critical to societal and environmental sustainability. Here present our theoretical and methodological work on how to construct tools for the achievement of the above goals as well as the results of testing our tools empirically.