Should neurointerventions be used to prevent crime? For example, should we use chemical castration as part of efforts to prevent re-offending in sex offenders? What about methadone treatment for heroin-dependent offenders? Would offering such interventions to incarcerated individuals involve coercion? Would it violate their right to freedom from mental interference? Is there such a right? Should psychiatrists involved in treating offenders always do what is in their patients’ best interests or should they sometimes act in the best interests of society? Tom Douglas (Oxford) briefly introduces these issues, which he investigates in depth as part of his Wellcome Trust project ‘Neurointerventions in Crime Prevention'