The situation talks back As the designer shapes the situation in accordance with his initial presentation of it, the situation “talks back” and he responds to the situation’s back-talk. In a good process of design, this conversation with the situation is reflexive. In answer to the situation’s back-talk, the designer reflects-in-action on the construction of the problem, the strategies of action, or the model of the phenomena, which have been implicit in his moves. What's wrong with the rational modelWhat the prototype tells youExpressing ideas helps to form themThe idea grows as they workDrawing as a means of thinkingFour principlesWriting, Briefly design