The opportunistic route and the role of design principles

This paper describes some aspects of the opportunistic mode of design which, it is held, most designers adopt, particularly for the step from concept to embodiment, or means to form, in which it is most characteristically seen. Simple examples are given which show the operation of constraints in directing the designer, and the strengths and weaknesses of the approach are discussed. Suggestions are made as to the important role design principles can play, and how their systematic introduction could help. Some notes are given on a computer aid which is being developed to prompt the designer in the use of appropriate principles at the appropriate stage in the work.