In 2003 the joint effort to design a European Spallation Source resulted in a set of reports. Two new designs were presented at PAC09 by ESS-Bilbao and ESS-Scandinavia. Both designs exploit synergies with projects such as SPL at CERN, eRHIC at BNL, and the EURISOL Design Study. Lund was agreed to be the ESS site in late May 2009. ESS- S then began to prepare for a coordinated European effort to update the design, and to prepare all legal and organisa- tional matters that will be needed during the construction phase. The design update phase is expected to end in 2012. The present status of the preparatory work is presented, to- gether with an outline of future work. The baseline for the updated design is presented and discussed. It delivers 5 MW of 2.5 GeV protons to a single target, in 2 ms long pulses with a 20 Hz repetition rate. Potential future up- grades of power and intensity are considered, with the pos- sibility of increasing the average beam power to as much as 7.5 MW, for delivery to one or perhaps two target stations.