Abstract. Research in many fields of AI, such as distributed planning and reasoning, agent teamwork and coalition formation, cooperative problem solving and action theory has advanced significantly over the last years, both from a theoretical and a practical perspective. In the light of the development towards ambient, pervasive and ubiquitous computing, this research will be tested under new, more demanding realistic conditions, stimulating the emergence of novel approaches to handle the challenges that these open, dynamic environments introduce. This paper identifies shortcomings of state-of-the-art techniques in handling the complexity of the Ambient Intelligence vision, motivated by the experience gained during the development and usage of a contextaware platform for mobile devices in dynamic environments. The paper raises research issues and discusses promising directions for realizing the objectives of near-future pervasive information systems. Key words: Ambient Intelligence,...