Children aged 6 to 12 who were exposed to intimate partner violence (IPV) within the last year participated in an intervention program found to be successful in reducing their internalizing and externalizing behavior problems. However, little is known about factors that may contribute to this efficacy. Both fixed and modifiable risk factors that predicted change in children's adjustment after the intervention were identified and tested. There was a significant relationship between the extent of exposure to IPV, gender, change in mothers' mental health, and change in child adjustment. Among fixed factors, length of exposure to violence was found to moderate the relationship between the amount of the child's and mother's participation in the intervention and change in child adjustment, specifically internalizing behavioral problems. Among the modifiable risk factors, change in mother's mental health, specifically symptoms of posttraumatic stress, was found to mediate the relationship between the amount of intervention participation and change in child adjustment. These findings can be used to inform and enhance evidence-based clinical services for children exposed to IPV.