ABSTRACT
The history of planning is full of stories about visionary ideas that have radically changed planning thoughts and practices. However, planning scholars have seldom studied ‘ideas’ as the object of their inquiry and to understand the relative analytical power of ideas, compared with interests or institutions, in explaining change or stability. As a first step towards studying the role of planning ideas, this chapter provides an overview of key debates in ideational approaches focusing specifically on discursive institutionalism. Drawing on the rhetorical appeal to ethos, it discusses why some ideas succeed while others fail.
