The objective of this paper is to measure the impact of different kinds of knowledge and external economies on the urban growth in an intraregional network of cities. The paper is divided in five sections. First section (theoretical framework) exposes the relation between the knowledge-based city, networks of cities, external economies and urban growth. Second section exposes a methodology for the measurement of knowledge in cities and the identification of knowledge-based networks of cities. Third section exposes a model to measure the effects of knowledge and external economies (static and dynamic) on the urban growth. Fourth section applies this model to a case study (Catalonia). Finally, conclusions and policy implications are exposed
