Several researches that we have conducted in our laboratory (CRESSON) have aimed at understanding the ambient milieu (among which sonic and optic environment) through one's experience. These works encourage us to consider an "ecological approach to architecture" which takes into account the human,
sensitive and social, experience in situ. It gives importance to the potentials of perception and action that an environment can afford to users. But it also questions the aesthetic criterias and the embodiement of ́ references a that guide architectural thinking. The purpose of this paper is to show and discuss results of researches that lead us to question how "ambience" could be a reasoning vector when conceiving architectural and urban projects and how
ambient references are build up and integrated in an architectural culture. The approach we use is indeed inspired and awakened by several researches in different domains such as that of perception or of sociological and architectural research. We briefly explain these references and their respective importance for an ecological approach. Then, we present two sorts of work according to their respective aims and a few examples of interesting results belonging to the fields of sonic environments and optic structures which could make reference. It will particularly concern spaces that create transition between different conxtets. They are important in
current life and as units of structuration in architectural composition.
Finally, we show the potential of development and we will draw conclusions.