This paper proposes a methodology for carrying out human-machine systems engineering research and in particular focuses on the development of knowledge-based support for training and aiding. The process is characterized by the definition of knowledge requirements, a normative model structure of human-machine interaction, a knowledge architecture that implements the model, and an interactive real-time simulation environment. The knowledge requirements largely specify the model, knowledge architecture, and simulation. The model and the knowledge architecture are the basis for the design of intelligent systems. The simulation serves as an experimental testbed that provides a feasible, safe, and effective means for exploring alternative human-machine systems designs and also facilitates technology transfer. The aim is to create an understanding of a complex work domain that forms the context for ongoing research in human-machine interaction. A specific example from satellite ground control is described.< >