Abstract: A method for preventing cheating by users of client computers running a network game program includes installing a monitoring program, independent of the network game program, on a group of the client computers so as to detect, using the monitoring program, an anomalous use of an asset of at least one of the client computers that is indicative of an attempt to cheat in the game program. A message is conveyed over a network to a server from each of at least some of the client computers in the group. The message from each such client computer indicates that the monitoring program has been actuated on the client computer. Responsively to the message, the client computers receive a message from the server at the client computer indicating which ones of the client computers have actuated the monitoring program.