Children's guilt associated with transgressions and their capacity for effortful control are both powerful forces that inhibit disruptive conduct. The authors examined how guilt and effortful control, repeatedly observed from toddlerhood to preschool age, jointly predicted children's disruptive outcomes in 2 multimethod, multitrait longitudinal studies (Ns = 57 and 99). Disruptive outcomes were rated by mothers at 73 months (Study 1) and mothers, fathers, and teachers at 52 and 67 months (Study 2). In both studies, guilt moderated effects of effortful control: For highly guilt-prone children, variations in effortful control were unrelated to future disruptive outcomes, but for children who were less guilt prone, effortful control predicted such outcomes. Guilt may inhibit transgressions through an automatic response due to negative arousal triggered by memories of past wrongdoing, regardless of child capacity for deliberate inhibition. Effortful control that engages a deliberate restraint may offset risk for disruptive conduct conferred by low guilt.