IUCLID (International Uniform ChemicaL Information Database) is a database including a tool for data collection on chemical substances. In particular IUCLID5 enables to prepare a registration dossier as well as to prepare other types of REACH dossiers (PPORD dossiers, C&L notifications, notifications of substances in articles, DU reports and Annex XV dossiers) as well as dossiers for other EU and international jurisdictions. REACH requires that registration dossiers are submitted to the Agency following IUCLID format. IUCLID5 is built using internationally harmonized formats for reporting data on intrinsic properties of chemicals that were prepared and accepted by many national and international regulatory authorities within the OECD.