Abstract.A traditional approach to system design is to optimize the system with regard to a set of system objectives, as defined in a given context. This approach falls short when designing systems that are capable of delivering sustained value to stakeholders in the face of a rapidly changing world. In order to achieve this value robustness, systems should be designed using natural value-centric time scales, as defined by their contexts, for conceptualizing system timelines. Epoch-Era Analysis is an approach that provides for visualization and a structured way to think about the temporal system value environment. This paper discusses Epoch-Era Analysis as central to a tradespace exploration process for system design comparison and selection, invoking passive or active value robustness design strategies. The analysis can also serve as a socio-technical bridge, integrating the tradespace exploration activities of architects and engineers, which may be traditionally independent efforts in contemporary engineering programs.