摘要： Floodlighting designs have only been analysed in terms of visual and aesthetic beauty up to now. Research in the field of floodlighting has also focused on other aspects of this type of lighting in recent years. The energy efficiency issue and the impact on light pollution are the most crucial aspects. These issues have not yet been properly explored in the literature. Significant factors which affect the issue of the engineering aspect of floodlighting have to be determined and studied carefully because of their high importance. The main aim of this paper is to present the key factors which have a crucial impact on energy efficiency and light pollution in the field of floodlighting. These factors are: the direction and location of the lighting equipment, luminous intensity distribution, light output ratio, the method of floodlighting and the spectral power distribution of a light source, as well as the spectral distribution of the reflectance from the illuminated surface. Each of these factors are precisely commented on. These are presented by means of a calculation, a measurement or a visualization example, which clearly allow the crux of the problem to be analysed in the easiest way. The research shows that the problem of improving floodlighting design in respect of energy efficiency and light pollution is a complex and exacting problem for a lighting designer. It definitely requires the creation of an individual and unified system of assessment. It ought to take into account all the crucial factors and be simple, understandable and easy to use. Development of such a system is underway at the Lighting Technology Division of Warsaw University of Technology. It will soon be finalized in the form of a doctoral dissertation by one of the authors of this paper.