Locking the door of adult acute psychiatric wards has become increasingly common in the UK. There has been little investigation of its efficacy or acceptability in comparison to other containment methods. We surveyed the beliefs and attitudes of patients, staff and visitors to the practice of door locking in acute psychiatry. Wards that previously participated in a previous study were contacted and sent a questionnaire. A total of 1227 responses were obtained, with the highest number coming from staff, and the smallest from visitors. Analysis identified five factors (adverse effects, staff benefits, patient safety benefits, patient comforts and cold milieu). Patients were more negative about door locking than the staff, and more likely to express such negative judgments if they were residing in a locked ward. For staff, being on a locked ward was associated with more positive judgments about the practice. There were significant age, gender and ethnicity effects for staff only. Each group saw the issue of locked doors from their own perspective. Patients registered more anger, irritation and depression as a consequence of locked doors than staff or visitors thought they experienced. These differences were accentuated by the actual experience of the ward being locked.