A system for the accumulation of detailed moment-to-moment information concerning the movements of players and of the ball in a sporting contest. One or more cameras (11, 12, 14) are situated so as to cover the entire playing area (10) of the event. The output of at least one of these cameras is provided to a digital image processor (22), which tracks the movements of the images, or silhouettes, of players in the camera images. By employing multiple camera views of the same playing area, the tracking processor can, in most cases, resolve ambiguities arising from overlaps in any one view. For the remaining, unresolved, cases, one or more human operators, provided with the same or similar camera views, are employed, through an interactive interface. The operators are provided with apparatus (30) for identifying players, through a query/response method, as requested by the tracking processor (22). The operators also provide initial player identification at the start of the event, and following breaks in the action, using the same apparatus. A varient system is described wherein the player identification task of the operator is performed, instead, by electronic tracking devices, such as radio transmitters, in conjunction with off-field electronics (60, 61, 67, 68), incorporating telemetry and triangulation in order to obtain identity and approximate position of all game participants.