The European Strategy Forum on Research Infrastructures (ESFRI) has chosen the Survey of Health, Ageing and Retirement in Europe (SHARE) to stand as one of the European Research Area's 35 crucial pillars. The current project prepared a major upgrade of SHARE for all EU-27 Member States as well as Israel and Switzerland, so as to establish a biannual panel survey over the course of the 2010-to-2020 decade. In the Acceding States, ageing presents a special challenge as populations are ageing before their social and health institutions have a chance to reach the same level of maturity as in the EU-15. SHARE has built a micro database to be used for better understanding individual and societal ageing as a process strongly influenced over time by pension, health care and labour market regimes and their reforms. Designed by and for researchers, the infrastructure brings together economics, medicine and the social sciences. The research it contributes to will serve as feedback in support of EU policy development and in response to the challenges of population ageing across the EU. The 'Upgrading the Survey of Health, Ageing and Retirement in Europe – preparatory phase' (Share-prep) project is to upgrade the SHARE prototype at the financial, legal, governance and technical maturity levels needed to fill in knowledge gaps in individual and population ageing. This called for a two-pronged approach. Firstly, the SHARE was extended in time so study subjects and their reactions to changes in their social and economic environments can be followed for up to 15 years. Secondly, the SHARE has been expanded to include all EU Member States. Share-prep's most significant outcome is a memorandum of understanding that supports the sustainable cooperation of the stakeholders and the statutes of the Share European Research Infrastructure Consortium (Share-eric).