Survey of criteria necessary to establish the diagnosis of Lyme disease according to its definitions by various organizations and institutions in the USA and Europe (European Union Concerted Action on Lyme Borreliosis, Centers for Disease Control and Prevention, The International Lyme and Associated Diseases Society). In the discussion the authors present other possible clinical manifestations connected with the involvement of various organs. In the second part of their paper they describe patterns of therapy for individual forms of Lyme disease in Europe and the USA and their differences.