The European Union roadmap for implementing nature-based solutions: A review.

• EU's roadmap for NBS theorisation and implementation. • The leading role of the EU in NBS operationalization. • NBS implementation is underpinned by a feedback loop of science-practice-policy. • NBS institutionalisation is a step forward. The present paper traces a chronological history, or roadmap, of the documentation produced by the European Union (EU) to promote and implement nature-based solutions (NBS) as an innovation action aiming to establish a socially inclusive, economically vibrant and ecologically resilient society. The EU's ambition is to position Europe as the world leader in NBS Research (via scientific research aiming at generating knowledge and theories) and Innovation (NBS implementation via identifying innovative approaches and best practices), as well as in a global market (for sharing, communicating, collaborating and promoting NBS). Considerable efforts have been made by the European Commission (the executive branch of the EU) as featured in a number of documents, funding programmes and Horizon 2020 (Research and Innovation) projects that span the period from 2012 to 2020. While the European Commission's commitment to promoting NBS within its Member States and beyond is still an ongoing process, we aim to review the efforts undertaken, knowledge gained, and practices accomplished. This roadmap intends to provide interested practitioners, policymakers, researchers, as well as civil organisations with an updated understanding of the leading role of the EU in NBS conceptualisation and operationalisation. This can inform future directions of NBS Research and Innovation actions, which in turn address environmental and societal challenges prompted by urbanisation/re-urbanisation, globalisation/de-globalisation, climate change and, more recently, the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]