The European Centre for Medium-Range Weather Forecasts (ECMWF) is an independent international organisation supported by 34 Member and Cooperating States, recognised as a world-leading centre for global numerical weather prediction (NWP). ECMWF is both a research institute and a 24/7 operational centre, producing and disseminating medium- and extended-range weather forecasts to its member states, worldwide commercial customers and international organisations (including the UN/WFP and IAEA). Moreover, ECMWF’s objectives also include the development of scientific and technical research directed to the improvement of these forecasts, and the collection and storage of appropriate meteorological data. To that effect, ECMWF operates a supercomputer facility that is one of the largest of its type, with the currently deployed 2 Cray XC-40 clusters ranked 25th and 26th in the June 2017 Top500 list, and an associated perpetual archive storing more than 200PiB of meteorological data. Furthermore, ECMWF pursues scientific and technical collaborations with satellite agencies, the European meteorological community and the world climate and weather prediction communities, as well as providing services for the European Commission.