Recent research implicates cognitive processes traditionally linked to anxiety disorders in the maintenance of paranoia. Responsibility beliefs have traditionally been associated with OCD, and recent research suggests they may be transdiagnostic. The present study reports the first data on responsibility beliefs in individuals with persecutory delusions. 30 people with persecutory delusions completed measures of psychotic symptoms and responsibility beliefs. Participants were also asked to identify who they held responsible for their persecution. Quantitative data on responsibility beliefs were compared with 29 matched non-clinical control participants, and with published data from patients with OCD and anxiety disorders. People with persecutory delusions identified a number of different entities responsible for harm. The persecutory delusions group had higher responsibility beliefs than those with OCD, anxiety disorders and nonclinical controls. The results suggest that responsibility beliefs are a facet of the phenomenology of persecutory beliefs. Cognitive-behavioural therapy for psychosis might usefully draw from OCD interventions and focus on responsibility beliefs, perhaps especially in Bad Me paranoia.