Green building-integrated systems and technologies (e.g., green roofs (GR) and walls (GW)) are classified as nature-based solutions (NBS) in the context of urban green infrastructure (GI), which contribute to add both natural elements and processes, as a result of locally designed, resource-efficient, and systemic interventions in cities. They have also been considered to address several urban challenges towards cities' circularity. The European Union (EU) Biodiversity Strategy and the Action Plan recently adopted by the European Commission, represent a comprehensive long-term programme aspiring to protect nature and reversing the ecosystem degradation by 2030. Sustainable and resilient societies under the challenge 'innovating with nature' are the leading aim of the EU Research and Innovation (R&I) policy agenda goals on NBS and re-naturing urban areas. The European GI/NBS Associations build the bridge to provide a network among stakeholders from academia, municipalities, entrepreneurs and private-sector entities and other non-governmental organisations, by creating a platform to build and share knowledge and create collaboration on sustainable GI/NBS, regarding building-integrated vegetation approaches as well as related policies, regulations and technical guidelines. The commitments of the foundations to encourage and promote the advanced adoption of green urban infrastructure practice and planning as part of the built environment, drive active efforts to support NBS innovation objectives and the transition from 'grey to green' infrastructure. The present manuscript aims at reflecting the crucial role of the Associations on GI/NBS, mainly GR and GW, to develop local frameworks applying innovative plans of action, and allocate R&I opportunities implementing relevant and inclusive urban regeneration solutions. Within this context, it will be highlighted the example of the Portuguese National Association of Green Roofs.