Despite its widespread use, there is a limited evidence-base for the use of Positive Behavioural Support (PBS) in secure forensic hospitals for patients diagnosed with mental disorder. The present study aimed to explore four staff and four patient experiences of PBS inside this setting, using Interpretative Phenomenological Analysis (IPA). Three superordinate themes were identified: ‘a desire for rapport’, ‘difficult emotions’, and ‘a challenging environment’ from patients and two superordinate themes, ‘a challenging environment’ and ‘compassion for patients’ from staff. The study found that PBS may require adaptations for secure forensic hospitals for mental disorder and more staff training and resources.