The study tried to clarify social adaptability of persons with brain injuries by using a long-term criminal development as a criterion. Randomly chosen 507 subjects whose open injury originated from the Second World War were followed up for about 30 years. The criminal acts commited by 29 (5.7%) of these subjects were so severe that they led to imprisonment. Criminality was not found in the subjects with fronto-temporal injuries more often than in those with injuries to the other areas. Subjects with injuries to the dominant hemisphere appeared to have more criminality than subjects with injuries to the non-dominant hemisphere. The criminal acts were often very accidental and had happened only after several decades following the head injury.