ABSTRACT
The urban system is an arrangement of towns held together by flows of people, goods and ideas. These flows constitute the dynamics of the urban system, the system's lifeblood. This chapter looks at the spatial arrangement of the urban centres and considers the dynamics. Rural-urban migration is the predominant form of movement in the third world. It was also important in the developed world of the nineteenth and early twentieth centuries. Throughout the twentieth century in Britain and the USA, for example, the importance of rural-urban migration has declined as inter-urban moves began to predominate. It is a sign of economic development when rural-urban migration is replaced by inter-urban migration as the dominant form of movement. In non-retirement migration the predominant reasons for movement are economic. People tend to move where there are jobs and better employment prospects.
