The possibilities of engaging outdoors risk in play in structured environments like childcare or schools are limited, due to a narrow focus on children’s safety instead of developmental benefits of challenging activities (Brussoni et al., 2015). Professionals willing to involve children in more risk-taking play are confronted with five barriers: cultural expectations, regulatory frameworks, parental beliefs and, on an individual level, personalized characteristics and their constructs of children (Van Rooijen & Newstead, 2016). To investigate how these five barriers influence professional practices, we will conduct a study using the approach of Realistic Evaluation (Pawson & Tilley, 1997). Realistic evaluation (RE) aims at finding an answer to the question ‘What works, how, in which circumstances and for whom?’. This method is therefore specifically suitable for studying social worlds, attitudes and effects in particular contexts. RE starts with formulating a middle-range theory based on existing theories, past evaluations and previous experience which provides an appropriate program for the specific setting. In analyzing the change ‘mechanism’ in the program more can be learned about participant’s reasoning and the working of appointed resources. In five different childcare settings the researcher will conduct a trajectory in collaboration with the professional teams. This study has three goals: a better understanding of the mechanisms behind the influencing factors in daily childcare situations, to grow professional awareness for potential barriers and in doing so to change attitudes and enhance possibilities for outdoor risky experiences of children in structured environments. In this session I want to discuss the study-design giving due notice to methodological issues as well as ethical considerations on intervening in children’s play environment. By examining barriers and how they inﬂuence individual practitioners in their speciﬁc context, more can be learnt about how to facilitate professional practice in enabling children taking appropriate risks in their play.