The innovative buildings by Le Corbusier, for example, give proof that light and architecture can achieve a perfect symbiosis. “A house is only habitable when it is full of light and air,” he stated in the 1920s, postulating an important architectural principle. Lighting design has since become a central element in contemporary architecture, in particular in outdoor areas. The design of the Ghost line is the outcome of a fundamental rethinking of the way outdoor lighting is conceived, thereby redefining its relation to the architecture in an innovative manner. This interesting concept of outdoor lighting is based on a basic principle of “subtraction” rather than the familiar approach of “addition”. No visible lighting fixture is added to the building’s structure; instead, it consists in a void filled with light. The aim is to make the light come directly from the structure, from the concrete itself. Ghost thus turns into a sign, a bright spot that appears or disappears, accompanying the rhythm inherent in the architecture. Ghost is a primary architectural element, similar to a brick, suitable to build almost anything from simple walls to entire cathedrals. Thus it is up to the ability and creativity of the designers to utilise these lighting elements for creating outstanding architectures.