Van Bueren A sustainable built environment: the institutional challenges Ellen M. van Bueren Delft University of Technology Interdisciplinary Research Programme The Ecological City Faculty of Technology, Policy and Management P.O. Box 5015 2600 GA Delft The Netherlands Phone +31 15 278 69 36 Telefax +31 278 64 39 E-mail: E.M.Bueren@sepa.tudelft.nl First prize winning essay for the 1999 Post-Graduate Essay Competition of Building, Research & Information, The International Journal of Research, Development, Demonstration and Innovation. This essay has been published in: Building Research & Information (2000) 28(1), 79-81. 1