On the basis of answers by clinicians to a questionnaire concerning the classification and staging of Lyme borreliosis, the following classification is proposed: EARLY LYME BORRELIOSIS Localized infection: Erythema migrans and borrelial lymphocytoma without signs or symptoms of disseminated infection. (Regional lymphadenopathy and/or minor constitutional symptoms may be present). Early disseminated infection: Multiple erythema migrans-like skin lesions. Early manifestations of neuroborreliosis, arthritis, carditis or other organ involvement. LATE LYME BORRELIOSIS Chronic infection: Acrodermatitis chronica atrophicans. Neurologic, rheumatic or other organ manifestations--persistent or remitting for at least 12 (or 6) months.