There are two sources of light in architecture; ‘natural’ and ‘artificial’. Natural light is provided by the sun. It is unpredictable, cannot be easily controlled and we must build our environment around it. Artificial light has evolved as a technological response to the need to illuminate our world after dark. Conversely, we can create and control it. We can design both the source and the subject. Throughout civilisation, architectural form has responded to the sun. Until the industrialisation of artificial lighting, technological constraints limited light sources to function and utility. We now live in an age where artificial sources offer as many possibilities for expression and the creation of architecture as the light of the sun itself.