Abstract. This paper describes the first attempt to introduce evolutionarily designed players into the international Robocode league, a simulationbased game wherein robotic tanks fight to destruction in a closed arena. Using genetic programming to evolve tank strategies for this highly active forum, we were able to rank third out of twenty-seven players in the category of HaikuBots. Our GPBot was the only entry not written by a human. “I wonder how long handcoded algorithms will remain on top.” Developer’s comment at a Robocode discussion group, robowiki.net/cgi-bin/robowiki?GeneticProgramming