The European Union aims to reduce net carbon emissions by 55% in 2030, and become climate neutral by 2050. These goals can only be met if it boosts carbon storage in terrestrial ecosystems, preferably while fostering socio-environmental co-benefits such as conserving biodiversity, adapting to climate change, and safeguarding socio-economic and cultural values. Both the IPCC and the IPBES have emphasised the great potential of ecosystem restoration and related nature-based solutions (NbS) for addressing the challenge. wildE introduces ‘climate-smart rewilding’ as an innovative restoration approach to create climate benefits while also addressing other socio-environmental needs. The project gathers a multi-disciplinary team of leading European experts to develop a research and innovation programme addressing the climate-biodiversity nexus in tight association with the socio-economic dimension of large-scale restoration. The team will also project scenarios to assess Europe’s rewilding potentials under diverse land-use and climate change futures. wildE will (i) generate comprehensive case-comparative data on European rewilding trends and outcomes, (ii) quantify the net social, economic and environmental benefits, synergies and trade-offs related to rewilding and alternative land-use options; (iii) develop cutting-edge projections for future land use and climate scenarios; and (iv) develop tangible and readily accessible decision-support and management guidelines to enable policymakers, conservation managers, communities, and the private sector to co-construct climate-smart rewilding strategies as effective NbS for meeting the EU’s climate and biodiversity targets. Embedded within an ambitious stakeholder engagement, communications programme, wildE research will enable climate-smart rewilding as operational large-scale NbS to effectively foster the natural capacity of Europe’s ecosystems for climate change mitigation, adaptation and biodiversity support.