The thesis is concerned with the development of innovative, robust design concepts for a class of systems called Information Decision Action (IDA) Systems. IDA systems are typified by Command and Control (C2) and Command, Control, Communications and Intelligence (C3I) systems as used by police, emergency services and the military - the two titles refer respectively to the human activity and the technological systems. The class of systems is much wider, however, and includes, financial, traffic control, business and even governmental systems where information is gathered, used as a basis for human decision-forming, and results in action, all in real, or near-real time. IDA system complexity stems largely from the dominance of robust human ac...