In the context of the construction of the business incubator, a strong environmental requirement is expressed in the programme. In our project, this structuring question is treated in conjunction with the problem of quality of use, thus making it possible to link architecture and environmental quality in a profound way. From then on, the building must be installed in accordance with the site's bio-climatic requirements. To do this we arrange the construction so that the major part of the working spaces is oriented to the south and enjoys a good light. Solar gains will be easily controlled by protective windscreens in front of the glazing. We simply organized the project into three programmatic strata. It is a search for rationality as intelligent simplicity. We prefer simple and functional spaces rather than artifices, difficult to maintain, witnesses of a fashion often passed once the construction carried out.