Aims and method To explore the beliefs and understanding of staff and patients at a secure mental health unit regarding clozapine monitoring, and to identify barriers to and facilitators of monitoring. Qualitative semi-structured interviews and focus groups were conducted with 17 staff members and six patients. Results Six key themes were identified. The key facilitator of effective monitoring was the motivation of staff to help patients to become independent and facilitate recovery. An important barrier was a lack of clarity around the roles of different staff groups in monitoring. Staff and patients widely supported the establishment of an in-patient clozapine clinic and perceived that it would prepare patients for discharge. Clinical implications An in-patient clozapine clinic is a robust mechanism for clozapine monitoring in secure settings. The barriers and facilitators identified here could be applied to other secure units to guide their systems of clozapine monitoring.