With the advent of electricity and electrically activated light sources, work has become increasingly independent of daylight. This move towards artificial light sources has led to the alienation of our natural predetermined circadian rhythms and has been imbibed so well in our daily lives that it appears that we have forgotten previous diurnal cycles. And yet, despite numerous technical innovations and developments, daylight is still preferred to artificial light – a fact that continues to baffle many experienced lighting specialists, especially those with an engineering background.