This proposal outlines a detailed plan for ensuring the sustainability of one of Europe’s leading social science research infrastructures - the European Social Survey, European Research Infrastructure Consortium (ESS ERIC). As a comparative general social survey the ESS needs to have generous national coverage to provide analytical power and ensure it keeps up with the changing scientific and research infrastructure landscape. Failure in one or more of these areas could damage or even destroy the infrastructure. This grant will substantially reduce the risk by securing the medium-term sustainability of the infrastructure and making it more resilient towards future challenges. The ESS has responded effectively to the ESFRI approach since it became an ERIC in 2013 and receives sizeable financial contributions from its members for core activities. ESS-SUSTAIN-2 aims to build on that support and creates sustainability through a structural strengthening of the ESS and by future proofing the infrastructure. ESS is not seeking another few years Commission funding to keep it afloat, an approach unlikely to yield long-term sustainability (and in any event these costs are now met by ERIC members). Rather it seeks a vital helping hand to help complete the transition of the ESS into a research infrastructure that is financially sound and scientifically equipped for the future. By developing links with the European Values Survey, establishing global partners, engaging with policy makers, harnessing technology to improve efficiency and cost effectiveness and launching the world’s first probability-based online panel, this proposal aims to give the European Social Survey the strongest possible foundation to succeed in the years ahead.