Abstract
The direction of the light which transmits a window is reversed in daytime and nighttime. It is considered that windows at night have the function to deliver internal various information to the outside. This research examined the psychological effects which window lights have on external pedestrians and neighboring residents. The experiment showed that the warm color window lights located in the first floor whose inside can be seen tended to improve various effects to the pedestrians who are in the street. The interaction was confirmed only by the position of the window, and the color of light. Evaluations of suppression of dumping garbage, etc. rose remarkably with the window of warm color light on the first floor.