Urbanisation is a historical as well as a spatial process. Therefore, this chapter discusses the nature and levels of urbanisation right from the ancient times to the present as a process of spatial transformation linked to development and social organisation. However, a major thrust is on the colonial urbanisation as it coincides with industrial development and expansion of service sectors. For this period there is plenty of data on urbanisation from the censuses of various countries. This chapter also highlights the differences in the nature of urbanisation in the developed and less developed parts of the world and also attempts to contextualise India’s urbanisation from a global perspective.