This article defines a low-carbon, livable city as an eco-livable city. One such city, the city of Portland, Oregon, has become well-known for its policies which promote a movement away from an automobile society and toward a more walkable, bicycle-friendly city. This article examines how Portland developed into a sustainable city through urban planning and participatory democracy. The article will analyze first the historical development of Portland＇s urban planning; secondly, its downtown plan and Metro urban growth boundary; and thirdly, the process by which Vison PDX, the Portland Plan and the city's comprehensive plan were initiated by three of its mayors since the start of the 21st century. Most important to note is the fact that Portland＇s citizens and its government are not competing, but collaborating through a process of co-production to create new public services and activity. That and the fact that many people are involved in the urban planning process, which itself is an ongoing discussion.