Aerospace systems have strict dependability and real-time requirements, as well as a need for flexible resource reallocation and reduced size, weight and power consumption. To cope with these issues, while still maintaining safety and fault containment properties, temporal and spatial partitioning (TSP) principles are employed. In a TSP system, the various onboard functions (avionics, payload) are integrated in a shared computing platform, however being logically separated into partitions. Robust temporal and spatial partitioning means that partitions do not mutually interfere in terms of fulfilment of real-time and addressing space encapsulation requirements. This chapter describes in detail the foundations of an architecture for robust TSP aiming a new generation of spaceborne systems, including advanced dependability and timeliness adaptation/control mechanisms. A formal system model which allows verification of integrator-defined system parameters is defined, and a prototype implem...