Photo courtesy matteroffact via FlickrIn this feature series, Grist will spotlight cities of all sizes that are taking innovative steps to build sustainability into everyday life. They’re promoting mass transit and renewable energy. They’re painting bike lanes and planting green roofs. They’re turning vacant lots into small farms.

As more Americans make their way back into urban centers, cities have the opportunity to forge new ideas and new practices that make it possible for people to work, eat, and entertain themselves without taking such a heavy toll on the planet.

Ellensburg, Wash., for example, figured out a way to make solar power affordable to ordinary folks. In Charlotte, N.C., residents overcame their car culture to build a sprawl-killing light rail system. Cities of the Future documents and applauds their efforts, and encourages other commuities to follow suit.