BUNDARAN Hotel Indonesia is a busy roundabout in Jakarta. An incessant flow of cars rounding the circle spew gases polluting the air. Not far away plants absorb the gases and refresh the air. They are found not on the roadsides, but on the rooftop of Hotel Indonesia where trees and shrubs grow luxuriantly. A covered pedestrian walk surrounds the green roofs on the 11th level of the hotel.

Many other high-rise buildings in Jakarta boast a similar