Reducing light pollution isn't rocket science
"Despite being easy to address we continue to allow light pollution to keep us awake, block out the night skies and confuse wildlife."
One of my pet hates - lights burning though the night in empty buildings. In Montreal I used to notice this a lot, but they would claim that it wasn't a problem as their energy was 'green'. However, there is more to it than just that:
"Light pollution is not simply an annoyance for those who wish to see the stars, but throws natural cycles off balance too ... inappropriate light could have a profound impact not just on the flying mammals, but on all manner of wild things from flowers and insects to turtles and birds."