Office sprawl has huge environmental consequences. Downtown locations are more efficient, but pose problems of their own, such as urban heat islands.

As our population grows, clean water is becoming an increasingly precious resource. Wiser use and conservation can help ensure an adequate supply.

A future with clean air and a stable climate hinges on our ability to cut energy use and rely more heavily on renewable sources.

Building materials can cost a lot: forest destruction, waste, pollution. But products made with sustainably harvested wood and recycled materials save natural resources.