For many years, daylight was the only efficient source of light available. Architecture was dominated by the goal of spanning wide spaces and creating openings large enough to distribute daylight to building interiors. Efficient artificial light sources and fully glazed facades have liberated designers from these constraints of the past. Advanced daylighting systems and control strategies are another step forward in providing day lit, user-friendly, energy-efficient building environments. These systems need to be integrated in to a building’s overall architectural strategy and incorporated into the design process from its earliest stages. Quality and quantity of light inside building are important factors that intensively influence occupants’ productivity and physiological performance. As a result, architects should insure adequate internal luminous environment by implementing either artificial light source or natural daylight. Daylighting strategies and architectural design strategies are inseparable. Daylight not only replaces artificial lighting, reducing lighting energy use, but also influences both heating and cooling load. Planning for daylight therefore involves integrating the perspectives and requirements of various specialties and professionals. Daylighting design starts with the selection of a building site and continues as long as the building is occupied [Fontoynont 1999].