How do Architects Design?

This study is proposes a descriptive model of the design behaviour of architects. In the first section a framework for the model is proposed. In the second section the framework is tested against empirical data. 11 information processing mechanisms are observed in the data. Eight of these: information acquisition, problem interpretation, problem representation, solution generation, solution integration, solution evaluation, perception and sketching, are used in developing design solutions. The three remaining mechanisms: design'plans,'transformation rules and design-symbols, represent the categories of the priori knowledge used in design. In the third section these three knowledge mechanisms are explored in detail using the results of two additional experiments with designers