The joint edition of the 6th edition of the RE(ACT) Congress and the 4th International Rare Disease Research Consortium (IRDiRC) Conference to be held in Berlin, Germany, from 11-14 March 2020 is being organized in collaboration with the European Joint Program Rare Diseases (EJP RD) and in partnership with Eurordis (European alliance of patient organizations) and RDI – Rare Diseases International (global alliance of people living with a rare disease).