This report summarizes the works of the Research Committee on “Optimum Facade Type Considering Light and Visual Environment” (from October, 2000 to March, 2003). The use of daylight to replace or supplement electric lighting in commercial buildings can result in significant reductions in energy and demand. Façade design is one of the determinants for use of daylight. In order to assist designers who intend to use daylight in buildings, the committee provides a brochure showing the effects of window conditions on light and heat introduced in buildings visually and plainly. Also, the committee reviewed the level of technology of the techniques for utilizing daylight.