The marketing authorization of allergen preparations for specific immunotherapy (SIT) for subcutaneous injection (SCIT) and sublingual immunotherapy (SLIT) at the Paul-Ehrlich-Institut (PEI) insures that the quality, safety, and efficacy of these medicinal products is proven. As finished products, these medicinal products are subject to official batch control tests, which provide evidence that only those products are marketed which conform to the specifications laid down in the marketing authorization procedure. Products for SIT prepared for a patient on the basis of the physician's prescription - so-called named patient products - cannot be subjected to a marketing authorization review. Therefore, they are not subject to the pharmaco-surveillance by the PEI regarding quality, safety and efficacy. This article describes the different marketing authorization procedures in the European Union (EU) and addresses the problems related to the marketing authorization requirements.