The Troyes public library stands at the rear of a MacDonalds restaurant car park in what is a far from enhancing built environment. In our design, therefore, the library does not present any façades as such, since any suggestion or composition of a façade would reflect the built environment, create a vis-à-vis and sustain a conversation with its neighbours. No façades, then, either at the front, on the sides or at the back; nothing that asserts authority within the project limits. The geometry of the building remains uncertain and elusive, all the more so given the blurring of distinctions between interior and exterior, front and back, matter and colour, written and built. The library is a phenomenon rather than a work, thanks to which it gains in openness, generosity and responsiveness. The presence of the building is constituted by the juxtaposition of large-scale elements arranged in strips or continuous layers. These elements are the false ceiling in gold-coloured mesh, the gridded false ceiling, the blue façade, the old wooden room, the storage rooms, the pink stairway, the yellow ambulatory, the text and the mezzanine. Since observers cannot take in all these devices at a single glance, they are forced to walk around and by doing so will acquire impressions of accumulation and depth, which serve as a metaphor of reading. All these elements elude the common scale of architecture and the library thus regulates its own relation to the town: it is, in itself, an urban landscape. These big elements might overwhelm, so their materiality is dissolved into colour. Transparent and colourful, it becomes light; opaque but saturated with colours, it is transformed into a simple value within a broader spectrum; bright and colourful, it is self-diffusing.