Is this system still fit for purpose? This question becomes critical in a system of systems because many unannounced changes occur throughout the system content and context during its operational life. This challenge arises in multiple usage domains such as defense, national security, industrial, financial, commercial or personal. A system of systems readiness assessment capability must be devised by the systems engineering activity and rigorously vetted during system development, deployment and evolution. The authors describe a set of candidate capabilities and technologies which may enable a comprehensive, fast and trusted assessment capability. Furthermore such assessment capability may be extended to aid in highlighting system resiliency shortfalls, diagnosing failures, and vetting proposed changes to any constituent system.