A system, considered as a set of interacting or interdependent component parts forming a complex/intricate whole, share common characteristics like the structure (Architecture), the behaviour (Functions and Performance) and the interconnectivity (Interfaces).
Complexity is linked to the not-heterogeneity of the components (that can be "systems" themselves) and to the use (Mission) requirements and how they are demanding and constraining.
GEA Space provides highly professional System Engineering services supported by their long and deep experience in defining and designing complex and high performance systems and, also, systems of systems.