Resumen
Urban sustainability is a key factor that must be considered at the local level, however, there are few studies that consider sustainability using the triple bottom line approach and apply it to a large number of cities. In this paper, we develop a sustainability city index based on the triple bottom line using an intellectual capital approach that attempts to solve the negative aspects identified in the main indices proposed in the existing literature, such as the use of: subjective weightings, an arithmetic average or index that is not comparable. Here, we have used information available in the Urban Audit database for 2009. The results for 158 cities in 24 European countries show that the cities with the best positions are in the northern European countries. German cities occupied the best positions in the three dimensions of sustainability, albeit with a slightly worse performance in the social dimension. Moreover, the proposal index is consistent, without redundancy among the variables considered in the three dimensions.