Lighting is a very important aspect of interior design. Interior designers have to carefully plan office lighting. Optimum levels of light in an office have a major impact on employee mood and alertness. Office lighting also accounts for a large chunk of the total energy consumption of an office and has a great impact on air conditioning due to the heat generated in the lighting fixtures. An interior designer or a lighting designer must therefore plan the lighting with the optimum light intensities but with minimum electrical and heat load. 
Studies have revealed that there is a connection between the body's circadian rhythm and the surrounding lighting. Higher color temperatures help keep us awake and alert while lower color temperatures do the opposite. There is a lot of science that goes into lighting design for call centres and BPO s which operate in shifts throughout the night. The lightcolor temperatures are carefully choreographed throughout the night to keep the employees awake and alert.
Various light fixtures from major lighting product manufacturers have come up with fixtures which mimic the color temperatures of the sun right from sun rise to sun set throughout the day. This way the office lighting is in tune with the outside natural light and helps keep the body's circadian rhythm working fine. Interior designers and lighting designers use a lot of software programmes to check the lux levels, lumen, glare and color temperatures from different fixtures to have the most desirable lighting effect.
The ideal fixtures for an office project are the ones that throw light downwards as well as onto the ceiling. Interior designers should avoid using fixtures that cause glare onto computer screens or those where the glare directlt hits the eye.
