Rare diseases are defined as those affected less than five in every 10 000 person in European Union. The purpose of this paper is to present activities, which make possible to stimulate research development and marketing of appropriate medicine for tretment of rare disease, named “Orphan” medicinal products. EU “Orphan” medicinal products legislation which entered into force in April 2000 is described. Definition of “Orphan” medicinal products as well as the procedure of designation and placing the products into the Community register is presented. Those incentives to industry are described, which are already five years very well implemented oh the European level mostly on the pre-authorisation phase of “Orphan” medicinal products development, but also in the registration process as well as the post-authorisation phase. Finaly, the first twenty “Orphan” medicinal products, which have been given positive opinion in the Community for the grant of a marketing authorisation till April 2005 are mentioned in this work. The real availability of “Orphan” medicinal products in the particular EU member states is analysed.