Far from standing in the way of architectural creativity, constraints related to sustainability can, instead, stimulate it. This becomes especially clear if they are considered from the beginning of the project. Following the publication of the book "From Spatial Development to Detail", Emmanuel Rey was invited to present his vision on the Internet site of the School of Architecture, Civil and Environmental Engineering (ENAC) of the Ecole polytechnique fédérale de Lausanne (EPFL).