With people spending most of their time indoors, an ever increasing demand for energy savings has placed the advantages on access of renewable energy sources. This Thesis, attempts to define a methodology for sustainable lighting design. Since there exists a common misinterpretation of defining sustainability due to artificial lighting energy consumption only, a counter action is needed to preserve the sustainability of luminous environments. Thus, the effort of this work is meant to explore the criteria of sustainability in order to reveal the greater context lighting of spaces pertains, than placing fluorescent fixtures to ceilings and claim sustainability. Day lighting has become an emerging feature of building design process, while the required energy efficiency of artificial light sources has banned the incandescent light bulb. LED´s are emerging on the market on a light-wave speed. The issue affects a large range of professionals and their decision making process for urban planning, including the building design professions, building management industries and communities.