Interdisciplinary and transdisciplinary approaches have become the core of important theoretical contributions during the last decade. Innovative research strategies and methods tackling complex subjects and contexts that deal with people-environment relations have been presented at academic conferences and seminars. One aim of this invited symposium is to not only improve our understanding of these approaches but also discuss the challenges to implementing them effectively in precise situations. The contributors to this symposium discuss contributions thathave made transdisciplinarity emerge as a new way of looking at the relationship between knowledge, science and society especially in the conext of urban research and professional practice. Collectively, the contributions in this symposium will provide an understanding of the differences between interdisciplinary and trandisciplinary approaches. They will specifically focus on the challenges for implementing interdisciplinary and transdisciplinary approaches in urban contexts and discuss what obstacles have been encountered and how more effective implementation can be promoted.