The purpose of the present study was to examine the maternal beliefs and practices regarding preschool children's proactive and reactive aggression, within a cross-cultural framework. Participants included 30 Aboriginal and 45 European Canadian mothers of preschoolers who provided their emotional reactions, causal attributions, socialization strategies, and parenting goals in response to children's aggressive behaviours. Results supported previous research that both groups of mothers generally responded negatively to both types of aggression, although there were differences in the extent of negative emotional responses expressed by mothers in the two cultures depending on the type of aggression. Mothers believed that reactive aggression was due to more external causes than proactive aggression and generally used more power assertive strategies in response to proactive versus reactive aggression. Aboriginal mothers were less anxious and used less power assertive strategies than European Canadian mothers. These findings speak to the importance of examining both similarities and differences in mother's beliefs and practices across cultures. (Contains 2 tables.)