In Chapters 2 and 3 we have concentrated throughout on planning on the urban scale. But in looking at the writings of Howard, Geddes and Abercrombie we saw that, increasingly from 1900 to 1940, the more perceptive thinkers came to recognize that effective urban planning necessitated planning on a larger than urban scale – the scale of the city and its surrounding rural hinterland, or even several cities forming a conurbation and their common overlapping hinterlands. Here, the development of the idea of regional planning, in one commonly used sense of the expression, begins.