Energy efficient buildings should make as much beneficial use of naturally available light as possible. Lighting is important because of the influence it has over occupant experience. Until about 50 years ago, the use of windows and plan form of buildings was very much influenced by the limits of natural light admission. The development of the fluorescent tube lamp made the deep plan office a feasible proposition but at the expense of noise pollution and frequency band discomfort. There was the added psychological penalty of reducing access to daylight and external views. It is only relatively recently that the importance of these benefits have been acknowledged.