Prisoners often use self-inflicted injuries and hunger strikes to try to influence their situation. This is particularly true of inmates whose cases are still eligible for appeal. These two kinds of self-inflicted injuries differ according to the social and penal characteristics, as well as the prisoners’ motives. Hunger strikes tend to be used by inmates who are older than average and relatively well integrated in their family and job, but charged with serious crimes. Their motives are directly related to the penal or judicial situation. In contrast, self-inflicted injuries are often made hastily by unstable prisoners without family responsibilities and who come from poorer than average social backgrounds. They are typically charged with crimes that do not carry heavy sentences. Their motives are more related to familial and personal problems or to detention conditions than to the principle of incarceration itself. Finally, these behaviors occur more frequently during the “slowest” moments of institutional life, such as the evenings, weekends, and holidays.