A short historical perspective is given of the evolution of the use of software for the realization of increasingly complex control systems. The state-of-the-art in designing computer-based control systems is discussed and highlighted with an example. Two major aspects of the difficulties encountered with the current approach to designing these systems are discussed as an introduction to a solution. The solution is in the form of SPICE, a system that makes large real-time control software less complex by adopting a highly modular and expandible software architecture. A description of the system's architecture developed is given and illustrated with a simple example. >