This study aims to determine the usefulness of the concept of Urban Metabolism for sustainable urban development. In this concept, the total of urban flows (like building materials, food and waste) together with the processes which transform those flows are metaphorically viewed as the metabolism of a city. The thesis starts with a search for a clear description of the concept. Existing literature is analysed and ordered in which two main conceptions of the concept are distinguished: Urban Metabolism according to a biological point of view versus an ecological point of view. The second part of the thesis deals with the value of Urban Metabolism for reaching sustainable urban development. Urban Metabolism relates mainly to flows of materials and energy. A roadmap is developed how to apply the concept for reaching a sustainable exchange of materials and energy between the urban system and the environment. It appears that Urban Metabolism provides a framework within one can systematically search for such a sustainable exchange. However, to be more useful it is necessary that Urban Metabolism research shifts from describing the urban system to applications which aim to understand and control the metabolic processes and flows. In the last part of the thesis special attention is paid to the value of Urban Metabolism in reaching sustainable development through optimizing the spatial structure of a city. There is a clear connection between the urban metabolism and the spatial structure: some of the largest urban flows (building energy, building materials, transportation energy) are influenced by the urban structure. However, at this moment the possibilities to integrate spatial components into the concept of Urban Metabolism are limited.