The development of the theoretical underpinnings (system properties and relationship to policies) and the theories and metrics (relationships between attacks, defenses, policies) will allow development methods to compare the Cyber Security and other properties of a system and consider the trade-offs among them for current and future systems. In addition, this research will enable the development of new technologies and supporting tools grounded on sound principles; it could help comparing capabilities among vendors of their technologies; it would encourage the creation of a new industry for security software engineering technologies; it will reduce costs by providing scientifically supported evidence of security properties rather than applying exhaustive testing to look for evidence of insecurity.