The clinical variability of chronic infections due to Borrelia burgdorferi is greater than previously thought. Three personal cases are presented in an overview, together with cases from the literature. Chronic spastic para- and quadriparesis, transverse myelitis and recurrent hemiparesis have been noted in such cases. Frequently, there is additional involvement of the cranial nerves. Chronic polyneuritis, mononeuritis multiplex, as well as plexus neuritis can also occur. Psychiatric manifestations can at times be predominant. Their spectrum ranges from agitated depressive states with suicidal ideas to the clinical picture of dementia. Due to the high percentage of positive antibody titre reactions in the normal population, reliable evidence of a chronic infection of the nervous system is based on the examination of the cerebrospinal fluid. Lesions seen on CT and MRI are mostly uncharacteristic and bear no clear-cut relationship to the disease. Neurological signs and symptoms can be improved by antibiotic treatment.