Globally, Universal Design (UD) is promoted as an evidence-informed approach for planning and designing accessible and inclusive public playgrounds, which are valuable sites for outdoor play in child-friendly cities. However, it remains unclear the extent to which UD has been implemented in public playgrounds. The purpose of this study was to explore the extent to which UD is implemented, from the perspectives of playground professionals in the Republic of Ireland. A descriptive, cross-sectional online survey was used to gather data. Data analysis revealed that playground professionals recognise the importance of UD for planning, designing, and providing public playgrounds for inclusion, and implement UD in various ways. Still, a lack of knowledge and good practice guides for embedding UD, constitute significant barriers. Numerous opportunities, initiatives and training prospects were identified to better support the implementation of UD. Moreover, further research with 'professional experts' and 'user-experts' is required to strengthen socio-spatial inclusion.