SPACE SQUEEZE: Tiny Singapore projects its population will swell over the next two decades, and its planners are studying underground living as a potential fix to the problems of overcrowding and strained resources.

ROOM TO GROW: New government plans — including closing golf courses and paving over some of the island's nature reserves — still lag the planned population growth. As a result, projects to put industry and other activities underground are already advancing despite the technical challenges and significantly higher costs of subterranean construction.

MORE IS MORE: The ruling People's Action Party sees a bigger population as crucial to its goal of transforming Singapore into what it calls a leading world city.