"Over the last half-century, the geography of employment has changed radically. Cheap energy, economic subsidies and short-sighted tax policy provided incentives for businesses to locate at, or relocate to, the regions' edges. Now, fewer jobs are in core cities.

Yet even before the recent energy and economic crises, smart leaders recognized that the purported savings of "job sprawl" are - like housing sprawl - offset by significant, if sometimes hidden, costs.

Among them: the need to build new infrastructure, including highways that immediately become clogged with traffic."

For the complete Philadelphia Daily News article, please click here.