Background The literature suggests that intersectoral collaboration is important to prevent attacks by radicalised persons with mental health issues, but it is not clear what this collaboration entails.
Aim To provide insight in how perceptions of radicalisation and mental health issues differ between mental health care and the security domain, and how this affects intersectoral collaboration.
Method Qualitative data were obtained through focus group discussions and interviews with professionals and training staff from mental health care and the security domain.
Results The focus in mental health was on treatment of patients, while safety dominated in the security domain. Collaboration was hampered by too little understanding of, and for, each other’s domain. The separation of radicalisation with mental health issues into prosecution or mental health care impaired an integrated approach. Privacy rules were experienced as a significant barrier for collaboration.
Conclusion Intersectoral collaboration works effectively if participants maintain their professional standards and only share information that is necessary and justified to make an effective plan. Many identified obstacles are more general in nature, and not confined to specific cases of radicalisation with mental health issues. Dutch Care and Safety Houses offer a sound base for intersectoral collaboration. Future professionals from different domains ought to be familiarized with each other’s (im)possibilities, tasks, and roles.