Background: whereas smoking bans inside secondary school buildings are relatively widespread, a smoking ban for the outdoor school grounds is less common. This study investigates why many secondary schools fail to adopt an outdoor school ground smoking ban. Perceived barriers and facilitators of stakeholders at schools without an outdoor school ground smoking ban were identified.methods: qualitative data were obtained from 60 respondents of 15 secondary schools. Semi-structured interviews were held with various key-stakeholders and a thematic approach was used for analysis.results: the perceived barriers and facilitators of the stakeholders fell into four categories: (1) socio-political characteristics (legislation and social norm), (2) school characteristics (policy, decision process, enforcement, resources, workforce conditions, communication and collaboration), (3) individual characteristics (support, knowledge, and target group), and (4) smoking ban characteristics (environmental factors, guideline recommendations, outcome expectations, and evidence).conclusion: the findings highlight the importance of legislation for outdoor smoking bans. Moreover, collaboration, communication and involving stakeholders during an early stage of the process should be stimulated. These results can support schools adopting an outdoor smoking ban, which is important due to legislation that will be implemented for outdoor smoking bans at educational institutes in 2020.