The city is of specific interest as a node for flows of energy and matter and a focal point for sustainable development.
Sustainable cities is a necessary condition for sustainable development.
This imply that contributions from technology, as well as from natural and social sciences are to be integrated into the curriculum of the school. The most important challenge for a graduate school with activities in the field of sustainability is to offer a framework for communication and learning among the research students and their supervisors, and to give the opportunities for collaboration between specialists from different disciplines. The ideal situation for a research student dealing with an interdisciplinary research task is to do so in a little group where all members are closely co-operating within the same project but each having different disciplinary perspectives. The supervisors, representing different disciplines, should be directly involved in the project and contributing to the group. The research student should also be involved in a larger group of research students and senior researchers.