A team-taught interdisciplinary undergraduate unit in Sustainable Development has been developed and run over the past two years at the University of Bristol. This has been a unique initiative for this university to take. As in most other research-intensive higher education institutions, teaching generally follows rather traditional disciplinary conventions, operating within departmental bounds. The initiative was unusual--and indeed ambitious--enough to gain the Higher Education Environmental Performance Improvement (HEEPI) Green Gown Award in teaching for 2007 (HEEPI is a project supported by the Higher Education Founding Council for England; http://www.heepi.org.uk/green_gown_awards.htm). There are both challenges and pleasures in designing and delivering a team-taught unit in a traditional university setting. This experience is outlined and evaluated here, giving consideration to both the practical and the more fundamentally philosophical issues encountered in the process. (Contains 4 tables.)