Recent research indicates there are a great many nonvisual effects of light on people. The control of rickets and the suntan effect are well understood. Less well known effects include synchronization of a number of physiological rhythms and prevention and control of infantile jaundice. Physiological and psychological effects also vary with the type of artificial light, whether it is from incandescent or cool-white or full-spectrum (daylight) fluorescent lamps. Student behavior appears to be favorably affected by full-spectrum lamps. Color also has an effect on people and their behavior. Research suggests that blues and greens tend to foster relaxation while shades of red or orange tend to induce activity. In discussions of windows versus windowless space, building occupants seem to favor the ability to view the outside world. If the effects reported in the studies that have been undertaken to date can be replicated, educators and school facility designers should be able to design classrooms capable of producing desirable and predictable student behaviors. (MLF)