RoboCup-2000 was the second world championship, RoboLog Koblenz participated in. To the best of our knowledge, RoboLog Koblenz is the only team in the simulation league, whose agents are programmed in Prolog. The main goal of our research is to make declarative agent programming possible, by writing the agents’ control programs in SWI–Prolog [6]. Procedural aspects of the agents’ behavior can be specified by statecharts, that have become part of the Unified Modeling Language (UML) [4]. See also the paper Towards a logical approach for soccer agents engineering in this volume.