Pedestrian injuries are a significant health risk to children, particularly those 5-9 years of age. Surprisingly, few studies have explored parent-related factors that may moderate this risk. We examined parental supervision choices in the context of child pedestrian experience, parent perceptual factors and varying levels of environmental risk. A series of street crossing scenarios were used to examine the roles of child, parent and environmental factors in determining parents' supervision choices. Parents recognised differing levels of risk across environmental conditions and altered their supervision choices accordingly. Child age and parental risk perception were significantly predictive of supervision choices. Our results demonstrate that parents assess multiple factors when determining the intensity of supervision necessary for their children. Notably, parents adjust their supervision in direct relation to changes in the physical environment. Implications of these findings for injury prevention and future research are discussed.