The issue of light pollution is a particularly complex one, with potential conflicts of interest between the utilities, environmentalists, astronomers, the lighting industry and various government departments. Energy politics are always a sensitive issue, and light pollution is no exception to this rule. The effects of light pollution on flora and fauna - including humans and their widely varying night-time activities - are often subtle and need extensive field studies to be quantified in a sensible manner. The conference represented by these proceedings attempted to bring together the astronomical community, the lighting industry, end-users, the utilities, and public authorities for a discussion, as well as an exchange of ideas and information that should create goodwill among these groups, thus contributing to making the global efforts to reduce pollution more efficient and effective. Radio frequency pollution was also discussed in the context of radio astronomy and its efforts to create radio-quiet zones in collaboration with the government authorities that allocate frequency bands to the various users - mainly the telecommunications industry - and to protect the major planned and present radio observatories of the world. The three-day conference was attended by more than 130 representatives from 12 countries of all the above-mentioned groups and a wide range of topics was discussed. Some of the highlights were: The presentation of the first world atlas of artificial night sky brightness; the article by the International Darksky Association on their world-wide efforts to curb light pollution; the laws controlling light pollution implemented in Spain and Chile; an overview of the work on radio frequency protection of sites; and an introduction to the topic from the Chilean point of view. Related topics in the book are light pollution education, aircraft contrails, space advertising (with an added document provided by the relevant UN commission), and an experiment on involving the population of an entire country in measuring sky brightness, by using the Internet and the media.

Table of Contents:
Discurso/Speech by Representante CONAMA.- Global Monitoring of the Night Sky Brightness by Satellites and the State of the Night Sky in Chile.- Modelling Night Sky Brightness at Sites from DSMP Satellite Data.- The Growth of the Artificial Night Sky Brightness over North America in the Period 1947–2000: A Preliminary Picture.- Preserving our Nighttime Environment: A Global Approach.- Protecting the Skies of Northern Chile.- The Photometry Laboratory at the UCV and the Light Pollution Regulations in Chile.- The Law of the Heavens of the Canaries.- Protection of Mauna Kea and Haleakala Observatories rom Light Pollution.- The IAU’s Effort to Control Light Pollution.- Lighting in the Countryside.- International Schools Education Networks for ight Pollution Control.- Precise Evaluation of Upward Flux from Outdoor Lighting Installations Applied to the Case of Roadway Lighting.- Lighting for a Secure and Safe Night-Time Environment.- Preserving the Night Sky at McDonald Observatory.- Sky Background at ESO — La Silla in the Visible and Near IR.- The Tololo All-Sky CAmera — TASCA.- Increasing the Chilean Awareness of Dark-Sky Preservation.- Research of the Impact of Lighting on nvironment and Humans.- Sports Lighting that Protects the Dark Sky.- Radio Quiet Zones.- Aircraft Contrail Pollution.- Advertising from Space: A Real Danger?.- Obtrusive space advertising and astronomical research.- How many Stars do we still See.- Light Pollution as a Policy Tool.