This study was designed to address two research questions. The first research question asked whether physical abuse victimization at the hands of parents/guardians, bullying victimization at the hands of peers, and the abuse x bullying interaction encouraged early involvement in substance misuse. The second research question inquired as to whether the victimization‒substance misuse relationship was mediated by variables proposed by various theories and research studies—specifically, cognitive impulsivity, negative affect, and low self-esteem. A moderated mediation hypothesis was tested in a group of 865 (417 boys, 448 girls) schoolchildren from the Illinois Study of Bullying and Sexual Violence who were 10 to 15 years of age at the time of initial contact. A path analysis performed with three waves of data revealed that physical abuse and bullying victimization predicted substance misuse with mediation by cognitive impulsivity, but there was no evidence of moderation. On the basis of these results, it was concluded that victimization, whether through parental physical abuse or peer bullying, increases cognitive impulsivity, and that cognitive impulsivity, in turn, encourages early involvement in substance misuse. The practical implications of these results are that interventions designed to counter cognitive impulsivity and encourage cognitive control may be effective in preventing children traumatized by physical abuse and bullying from entering the early stages of a drug or substance using lifestyle.