As towns and cities worldwide deal with fast-increasing land pressures, while also trying to promote more sustainable, connected communities, the creation of green spaces within urban areas is receiving greater attention than ever before. At the same time, the value of the ‘green belt’ as the most prominent model of green space planning is being widely questioned, and an array of alternative models are being proposed. This book explores one of those alternative models – the ‘green wedge’, showing how this offers a successful model for integrating urban development and nature in existing and new towns and cities around the world. Green wedges, considered here as ducts of green space running from the countryside into the centre of a city or town, are not only making a comeback in urban planning, but they have a deeper history in the twentieth century than many expect – a history that provides valuable insight and lessons in the employment of networked green spaces in city design and regional planning today. Part history, and part contemporary argument, this book first examines the emergence and global diffusion of the green wedge in town planning in the late 19th and early 20th centuries, placing it in the broader historic context of debates and ideas for urban planning with nature, before going on to explore its use in contemporary urban practice. Examining their relation to green infrastructures, landscape ecology and landscape urbanism and their potential for sustainable cities, it highlights the continued relevance of a historic idea in an era of rapid climate change.

Urban agriculture (UA) can be used as an action to promote sustainability in cities and inform public health policies for urban populations. Despite this growing recognition, its implementation still presents challenges in countries in the Global North and Global South. Background: In this context, this systematic review aims to identify the development of frameworks for the implementation of UA as a sustainable action and its main opportunities and shortcomings in meeting urban socio-environmental demands. Methods: In this review, using the PRISMA protocol, we evaluated 26 studies on the interplay between UA and sustainability surveyed on the Web of Science to provide an overview of the state of the art. Conclusions: In summary, it was possible to identify many key challenges in UA adoption, which regard air and soil contamination, availability of green areas, layout of urban infrastructure, food distribution, among others. Due to numerous socio-economic and environmental contextual factors in cities, especially when comparing realities of the Global North and Global South, there is a need to develop a model that can be adaptable to these different contexts. Thus, it is recognized that the concept of sustainability does not present a universal understanding and that in its search it could be argued that one of the most important gaps is still to address social issues in relation to environmental ones.

Recent international policy advocating for social innovation to be part of strategies to promote sustainable urban development has energised this emerging body of literature. However, there is a need for more sector-specific research to integrate findings on the spatiality of social innovation, co-operative processes, and place-scale relations. This article presents a review (2002–2018) of social innovation in urban spaces. Based on data from 114 publications, the review indicates that research in the spatiality of social innovation can be grouped into three major themes: (1) Spatial planning and community development; (2) Governance; (3) Co-production and service design. The findings suggest that in general the collaboration of end users in place-based development is central to this process of urban change and that process is as significant as the outcome. This article concludes with a research agenda to address identified lacunas.

Urban populations are increasing at a rate that challenges existing public health infrastructures, while contemporary literature proliferates in the attempt to identify links between city neighbourhoods and health and well-being. Despite this, there have been few attempts to synthesise research into neighbourhood features perceived by elderly residents to affect their health and well-being. The primary objective of this review is to establish whether and, if so, how the perception of urban environment features acts as health and well-being determinants in an ageing population. Data extracted from 49 eligible articles into five key neighbourhood domains and thematic analysis show that poor health and reduced activity are associated with negatively perceived environments. In addition, urban social cohesion, crime and safety influences activity choices. Higher activity is associated with more compact and varied land-use mix with appealing aesthetics. Isolating individual perceived neighbourhood features as directly associated health determinants among the elderly is complex due to interrelations and overlap between domains. Identification of perceived environment health and well-being barriers or facilitators by the elderly are under-represented and warrants further investigation. Participatory objective and subjective research will contribute towards a more robust evidence base for public health professionals and policymakers by identifying knowledge gaps.