Beyond optimal city size: An evaluation of alternative urban growth patterns

The aim of the paper is to present a critical view of theoretical works on city size. We begin with the consideration that, during the 1960s and 1970s, the question of optimal city size tended to be expressed in a misleading way. The real issue is not 'optimal city size' but 'efficient size', which depends on the functional characteristics of the city and on the spatial organisation within the urban system. Economies of scale exist up to a certain city size. However, urban development generates conditions leading to structural readjustments which may create new economic advantages. These structural adjustments may either be sectoral transformations towards higher-order functions, or increases in external linkages with other cities. The paper provides empirical evidence of these processes, and contains an econometric evaluation of urban location benefits and cost functions with respect to different levels of network integration, size and urban function. The model is applied to 58 Italian cities.