This study concerns the development of a training program with regard to the prevention of violent radicalisation and polarization, for park guards and park animators. The park guards and park animators were designated by Brussels Prevention & Safety as first-line actors to deal with these problems. On the one hand, park guards can be confronted with radical behavior or radical language of users and they must have the tools to identify this and to deal with it in the right way. On the other hand, professionals themselves are sometimes confronted with a certain polarization, which can have negative consequences both within their own team and for the relationship with users.