Imagining the evolving spatiality of metropolitan regions

There is no simple or single definition of what a metropolitan region is, nor a threshold by which a region becomes a metropolitan region. Like all spatial concepts metropolitan regions are imagined, with different actors having their own vision of what metropolitan regions are and are for. In this chapter we trace the evolving spatiality of metropolitan regions before a series of illustrative cases highlight the importance of understanding nationally and regionally specific forms of metropolitan imaginary. Our aim is to illuminate the importance of understanding how metropolitan regions are imagined and mobilised as one central pillar for uncovering the dynamics of, and scope for influencing, metropolitan development.