Results revealed that self-protection of any kind apparently reduces the probability of the robbery being completed. Armed resistance is more effective than unarmed resistance; resistance with a gun, although relatively rare, is the most effective victim response of all. Resistance with a gun also appears to reduce the likelihood of the victim being injured. However, two types of resistance appeared to increase the risk of victim injury: (1) unarmed physical force against the robber and (2) trying to get help, attract attention, or scare the robber away. The robber's possession of a gun also appeared to inhibit victim resistance, which can sometimes provoke a robber to attack; robber gun possession thereby reduces the probability of victim injury. However, even controlling for victim resistance, robber gun possession is associated with a lower rate of injury to the victims. Tables and 45 references (Author summary modified)