Nature-based Solutions (NbS) represent a key approach to improve air quality, microclimate, health and well-being of urban populations. The European Commission will adopt in 2021 a zero pollution action plan for air, water and soil and it is known that especially air quality has a tremendous effect on human health and premature mortality. Other than contributing to air quality, NbS can be very useful in reducing the urban heat island effect which is affecting thermal comfort but also the carbon footprint of our cities. Improving air quality and microclimate has significant effects on a number of human diseases but NbS can also directly act on mental health and on brain development. This report highlights the combination of environmental and social benefits presented by different kinds of NbS. The role of NbS, including both green and blue spaces, arises here as an opportunity to achieve the ambitious sustainability targets of the European Green Deal.