The implementation of urban Nature Based Solutions (NBS) projects is deeply determined by the novelty of the concept. Its innovation is both an opportunity and a challenge: as a new concept, it generates uncertainty due to lack of technical and operational preparedness, but it also allows to deploy innovative approaches, new ways to address old problems and more inclusive practices. Nature4Cities project has systematically conceptualized the barriers and drivers on NBS projects implementation by a review of the state of the art. To see how these barriers can be overcome by governance strategies, different urban and environmental governance models have been mapped and characterized to assess their suitability for different NBS projects. Five clusters have been identified where models are grouped according to the involved actors, their position in the spectrum from high to low government involvement and their level of participation. This theorical model has been applied to real cases to check the incidence of the different clusters. Results show that urban and environmental governance is a map where the different models coexist in different degrees regarding some key axes such as level of innovation, polycentric vs. monocentric, involved sectors, level of participation and scale. Collaborative, multisector, polycentric and adaptive governance models address significant number of previously identified cross-domain barriers showing their suitability. The work presented in this paper can be the basis to define new institutional and governance arrangements that will foster multi-stakeholder involvement, citizens’ engagement, leveraging both public and private funding of NBS in cities

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