Man-machine interactive games simulating naval duels are being conducted at the University of Pennsylvania. The players act as the commanding officers of their respective vessels. They navigate, detect, and analyze their own and their opponent's activities in the duel. This report describes the two-dimensional displays employed in the conduct of the games. The displays describe in graphical form actual history of movements and the estimated history of movements of the opponents. The information for these displays is derived from navigation records and sonar readings that are ordered by the respective players. The use of the displays is illustrated through scenarios of two games. The importance of speed in presenting displays to players is one of the prime conclusions resulting from the completion of the game with the aid of the display.