Engineering design is a complex cognitive skill differing from possession of knowledge in tactical use of knowledge to achieve goals under constraints. An operational definition of a design must satisfy a set of constraints and objectives. Several published theories about the design process in terms of the criteria developed leads to the elaboration of hypothetical model of design behavior. The assumed model of design behavior predicts that the design behavior can be determined by measuring the information interchange between the designer and his environment. The use of real-time interactive graphic methods is an educational environment and is discussed in terms of the expected advantages and disadvantages of the approach. (Author)