When Jason Roberts wanted to improve his neighborhood in Dallas, he found many of the things that make cities livable — flowers planted on the street, café tables, trees and bike lanes, were actually illegal or came with a heavy fee. So he decided to do them anyway for a single block over a single weekend to help people visualize how welcoming their community would be with this forbidden features.

Storefronts were decked out as temporary stores. Trees destined to be planted at a hotel made a two-day rest-stop at Roberts’ barren block. Guerilla city planners painted a verboten bike lane. A bike tour was organized that drew 150 riders. Then people were invited to shop at the temporary boutiques and eat at temporary outdoor cafes.

After neighbors and city officials enjoyed the event, the neighborhood began to change to match that vision. City ordinances were amended to allow more neighborhood-friendly amenities. One of the fake stores, an art studio, stayed on and became a real one. And that was just the beginning. He told the story breathlessly for a TED talk.

Roberts and the organization he co-founded, Team Better Block, continue to work at making Dallas a more livable city, and not just for those folks who drive cars. He’s the opening keynote speaker at Greentopia’s Futures Summit Oct. 21 at Monroe Community College. To find out more about the summit or register, visit here. And dream about a better city.