ABSTRACT
Artifi cial outdoor light at night is a controversial issue. It provides undeniable value for the society; it changes the way of living and, in many ways, improves the quality of life. Nevertheless, the negative impacts of light have gained attention during the past years. Highly lit nights impact the natural rhythms of day and night and have effects on ecosystems and the human body, on energy consumption and the visibility of the stars. Light pollution has become a popular study subject-mostly, however, only in single-disciplinary analyses. In contrast, a comprehensive review of positive and negative effects of artifi cial outdoor light at night is still absent. This chapter is a fi rst attempt to comprehensively analyse the costs and benefi ts of artifi - cial light at night and to ask for the possibilities of an economic assessment.
