Previous research has linked prior acts of animal cruelty to later aggression toward humans, particularly among incarcerated populations. However, few studies have examined the circumstances surrounding animal cruelty, including how this behavior is learned and who perpetrators tend to be. The current study gathered self-reported questionnaire data from 261 male inmates in order to explore whether exposure to animal cruelty and the age of exposure affects inmates’ subsequent acts of animal cruelty. Specific variables under consideration were race, education, residence, witnessing of animal cruelty, age of witnessing animal cruelty, and whether the animal abuser was a family member, friend, neighbor, or stranger. Results of multiple regression analyses indicated that animal cruelty is indeed a learned behavior. Participants who witnessed animal cruelty at a younger age and at the hands of a friend were more likely to repeatedly hurt or kill animals themselves. The implication is that the onset and recurrence of animal cruelty may be influenced by members of the participant’s primary social environments, such as family and neighborhood. Future research should continue to probe animal cruelty as a learned behavior so practitioners can develop effective interventions. Tables, references