No matter what the lighting situation, the proper wattage, not overkill, should be used, and all light should come from full-cutoff, shielded fixtures. Low pressure sodium lighting is ideal for many of these applications because of its very low operating cost. However, persons involved in environmental causes must carefully define the problem they want to solve, learn the facts, appreciate the legitimate perspective of their opponents, and offer people solutions rather than complaints. This is IDA's philosophy and modus operandi. Light and radio pollution are solvable problems if the facts are properly conveyed to the public.
Light pollution is the one form of pollution whose solution immediately saves money.
Not just astronomers care about light pollution and light trespass. IDA's Board of Directors consists of a physician, a lawyer, two lighting designers, a city streetlighting director, as well as professional and amateur astronomers. Many IDA members are not astronomers or even particularly interested in astronomy. They are concerned about energy conservation, preservation of our environment, and proper nighttime outdoor lighting. They include homemakers, scientists, lawyers, pilots, doctors, engineers, retired persons, and so forth.