Unintentional injuries are the leading cause of death for children. Prior research has implicated both child behavioral attributes and parent supervisory patterns as risk factors. The present study assessed interactions between these two risk factors and determined whether supervision moderates the relation between child attributes and injury. Mothers completed questionnaire measures of child attributes and supervisory patterns and also recorded how they supervised their young child (2-5 years) at home on each of 10 randomly selected days within a 3-week period. Results provide support for the moderating effect of supervision: Supervision interacted with some child attributes to elevate children's risk of medically attended injury and with other attributes to decrease injury risk. Implications for preventing childhood injuries are discussed.