The modes of diffusion of ideas that shape planned environments, and the ways these ideas are realised, have been gaining prominence as subjects of study and discussion among planning historians and others. However, most studies have focused on the diffusion that has occurred within the sphere of the so-called First World, where the participants have been considered as relatively equal partners. On the other hand, where the diffusion took place between the First and Third Worlds, these exchanges have often been projected as one-way impositions where the receivers are silent, oppressed, impotent ¡ if not outright invisible. More recently, some researchers have begun to approach the relations between actors and stakeholders in processes of planning diffusion in a more complex and ambiguous way. To begin with, the natives in developing countries, whether colonial or post-colonial, are being recognised as fully-fledged actors in the shaping of the built environment, with a variety of roles to play and means to play them, even if they frequently face many constraints to their actions. Moreover, the planning influences have started to be acknowledged as going in multiple directions, including back to the source of dissemination. Adaptation, hybridisation, mimicry and appropriation are just some of the forms of diffusion and adoption that are relevant. The specific traits of the indigenous also came to be viewed as something that is not necessarily evident: ultimately, who are the locals℗? Urbanism ¡ Imported or Exported? is the first book to examine the full complexity of these issues in detail. It raises conceptual questions concerning the identities of locals, the roles of relevant actors, and the modes of diffusion, as well as investigating the methodological implications for historians of the city-building process. Using examples from around the world, with a particular emphasis on Mediterranean countries, it offers a bold new approach to the concepts and methods of the study of planning history.