Prison violence is probably increasing at a faster pace than violence in the free community and the impacts of violence and the threat of violence on the quality of life in prison is a major concern. Violence begets fear along with more violence, and violent incidents do not have to be common to elicit these responses. The variations among institutions make any generalizations about collective or individual violence unreliable, but experience suggests that negotiation and restraint are the appropriate response to any collective violence situation because preserving life is the major concern. The most deadly use of force in prison riots has been by authorities attempting to either control rioters or free hostages. Studies of sexual violence in prisons show that, in addition to being white, targets for abuse tend to be smaller, younger, disproportionately from nonurban areas, less likely to have a violent past, and to show high rates of attempted suicide and mental hospitalization. All of the above observations about violence in prison indicate that incidents depend upon the interaction of three variables: the aggressor, the victim, and the situation. This leads to the conclusion that changes in any of these factors would change the likelihood of violence, and hence, suggests that appropriate matches between offenders and environments may reduce aggression. Elimination of prison violence is not possible, but monitoring present subsettings and scanning for new ones could reduce the probability of victimization for the most vulnerable. This chapter contains an extensive survey or literature on violence in prisons, including interviews with prisoners, and 169 footnotes.