We have spent too much time—and for far too long—on the notion of sustainability and the ideal of sustainable cities. These initiatives have occasionally produced remarkable achievements, demonstrating significant advancement in a few cities or regions, but in many other situations, they have produced disjointed, halted, or superficial benefits. With bold plans and noteworthy accomplishments, some communities have adopted astounding development trajectories, while others have only managed to make a small difference. We see stalled progress in important areas of development in many regions of the world, frequently because of misaligned goals, political exhaustion, or inconsistent vision. The moment has arrived to create a transition from aspirational rhetoric to a real framework of commitment, a change from what we want to become to what we now need to actively seek and create.