Using a non-equivalent control group design, this report evaluated a previously studied behavioural intervention, the Stamp-in-Safety programme, which is designed to reduce the injury risk for young children on playgrounds at childcare centres by increasing the quality of adult supervision and rewarding children for safe play. In an urban, commercial childcare centre, 71 children aged 3-5 years and 15 teachers participated. Primary outcome measures were teacher verbalisations (warnings, explanations, redirects), teacher location (core, outskirt, or fringe of playground), child risk-taking behaviours (using equipment appropriately) and the number of injuries on the playground. Analyses revealed that the intervention had a modest positive effect in promoting safer teacher and child playground behaviours. This study reaffirms previous results that the Stamp-in-Safety programme is an effective method to decrease the risk of playground injuries at childcare centres.