ABSTRACT
It is suggested that the designer passes through a succession of stages, from receiving his initial directions to the production of a set of executable instructions for the manufacturer or builder. In a design text based on the Beaux Arts approach, the advantages of a logical progression of steps within each successive phase were stressed. Recently, interest has developed in attempting to externalize the structure of the design process as a basis for developing more rationally organized and effective design strategies. One of the earliest and simplest models to appear was evolved about ten years ago by Denis Thornley and his colleagues at Manchester University. Appropriate organizational structures and explicit objectives are prerequisites for developing such a mechanism; however, effective evaluative techniques are also required.
