Understanding factors that influence mothers' beliefs about appropriate levels of supervision for their children may assist in efforts to reduce child injury rates. This study examined the interaction of child (i.e. age, gender, and injury risk behavior) and maternal perception of environmental hazard (i.e. hazard level, injury likelihood, and potential injury severity) variables in predicting mothers' beliefs about appropriate levels of supervision for their children. Participants were 58 mothers of 2- to 8-year-old community children who were interviewed about their beliefs regarding child injury risk and appropriate supervision. Results indicated that perceived environmental hazard level interacted with child age, gender, and injury risk behavior to predict mothers' beliefs about supervision. Perceived injury likelihood also interacted with child injury risk behavior to predict beliefs about supervision. Findings underscore the complexity of factors influencing mothers' beliefs about appropriate supervision and indicate the importance of environmental hazard level in such beliefs.