Violent offenders often articulate offense-supportive cognitions during rehabilitation, yet these statements have received little theoretical attention, and intervention approaches have targeted each type of statement individually, as if they were unrelated. An implicit theory approach to cognitions has proved fruitful for research and intervention. The authors apply it to violent offenders. The first study presents a grounded theory investigation of offense-supportive cognition in prisoners attending an intensive rehabilitation program for violent offenders. Analysis of offense transcripts enabled the identification of several implicit theories. These results were refined with a second sample and trialed in the rehabilitation program. Findings suggest that several implicit theories held by violent offenders are linked to each other through the widespread normalization of violence. Few offenders experienced their violent behavior as abnormal, or completely outside of their control, once initiated. The authors make suggestions for enhancing the empirical status of this research domain, particularly through experimental investigations.