Abstract The use of light at night continues to increase. Simply put, this is because without light we are deprived of our premier sense, vision. By enabling vision the use of light at night delivers a number of benefits to people. Such benefits include greater safety for pedestrians and drivers, reduced fear of crime, more use of outdoor facilities after dark, enhanced economic growth and the creation of built and natural environments that are a source of beauty and entertainment. This suggests that the use of light at night is linked to some very basic human motivations which in turn means that people value such benefits and will not willingly abandon them. Fortunately, careful lighting design, soundly-based outdoor lighting standards and new lighting and sensor technology offer the possibility of providing the benefits of light at night while minimizing the impact on the environment.