Abstract: The European Organisation for Rare Diseases (EURORDIS) represents more than 280 rare disease organisations from 33 different countries, covering more than 1,000 rare diseases. It is therefore the voice of 30 million patients affected by rare diseases throughout Europe. EURORDIS is dedicated to improving the quality of life of all people living with rare diseases in Europe. To this end, it advocates for rare disease patients at EU and national levels. EURORDIS was instrumental in the adoption of the EU Regulation on Orphan Drugs and Medicinal Products in 1999 and of the EU Regulation on Paediatric Dugs in 2006. Some of the key factors in Eurordis’ success in terms of advocacy and policy development are: a broad membership base from all over Europe; transparency and financial independence; development of positions papers and contributions to key rare disease topics; collaboration with key EU platforms and institutions; proactiveness; and management of projects aimed at improving rare disease patients’ life conditions and increasing knowledge on rare diseases.