The risk and safety of specific immunotherapy (SIT) has been the subject of many well-designed studies since it was introduced. Most authors consider SIT an efficient and safe mode of treatment despite the occurrence of life-threatening anaphylactic reactions. They emphasize the importance of a proper selection of patients as well as the requirement for highly qualified physicians to provide the treatment. Another problem associated with the safety of SIT is the potential enhancement of the synthesis of immune complexes after the treatment. SIT causes a decrease in allergen-specific IgE which is slower in circulating immune complexes than in the serum. No data are available to show that SIT induces immune-complex diseases, in either the immunologic or the clinical sense. As far as anaphylactic reactions are concerned, new alternative methods different from the conventional parenteral mode of delivery seem to be safe. Our increased understanding of the altered functions of the immune system justifies the assumption that the more specific the method of SIT administration, the more effective and safe it is.