This is Volume III of thirteen in a collection on Urban and Regional Sociology. Originally published in 1967. A basic feature of the life and organization of advanced societies is the cohesion of socio-geographic groups at various levels. There are many aspects to this field of study. For this work is selected for examination the role of the central place—be it hamlet, village, town, city, or metropolis—as a focus of human activity and organization and leadership in the service of a surrounding tributary area. This field of study has been called 'human ecology' in the United States and 'social morphology' in France.