Christian Freksa is Professor of Cognitive Systems in the Department of Informatics at the University of Bremen and Director of the Transregional Collaborative Spatial Cognition Research Center SFB/TR 8 at the Universities of Bremen and Freiburg. His research concerns representation and reasoning with incomplete, imprecise, lean, coarse, approximate, fuzzy, and conflicting knowledge about physical environments. Particular emphasis is on the development of ‘cognitively adequate’ qualitative approaches in spatial and temporal domains. His interdisciplinary research group employs formal and computational approaches to knowledge representation, designs computer models for simulation studies, and carries out autonomous robotics experiments using diverse intelligent technologies. Christian received a Ph.D. in Artificial Intelligence from the University of California Berkeley. He carried out postdoctoral research in knowledge representation at the Max Planck Institute and built up the AI/cognition group at TU Munich. In 1991 he became Professor for artificial intelligence / cognitive science at the University of Hamburg before he moved to the University of Bremen to establish the SFB/TR 8. Christian Freksa is a Fellow of the European Coordinating Committee for Artificial Intelligence (ECCAI) and a member of the Advisory Board of the journal Spatial Cognition and Computation.