Tactical Urbanism in Seoul
Usually transport planning is directed by local authorities and citizens have limited possibilities to directly transform their surrounding. Or in other words, it is a top-down development that includes public participation through formal procedures. There are exceptions and examples of bottom-up approaches, organized by private entities or local groups. Such a grassroots development can be described as tactical urbanism (or guerilla urbanism). For literature about that concept, I recommend The Street Plans Collaborative. In Seoul there are two very interesting examples of tactical urbanism.