ESS is a joint European project like CERN in Geneva. Over the past ten years, several countries have offered to be host. There have been two proposals in Germany; in the cities of Jülich in the vicinity of Düsseldorf and near Halle next to Leipzig. In Great Britain, proposals have been presented by Oxfordshire and Yorkshire. The Basque region in Spain is working for a location in Bilbao. Hungary has proposed several possible locations, but chose Debrecen in December 2007.
Since the site decision was made in May 2009 both Spain and Hungary have joined ESS in Lund as partner countries.