Rapid urbanisation generates risks and opportunities for sustainable development. Urban policy and decision makers are challenged by the complexity of cities as social–ecological–technical systems. Consequently there is an increasing need for collaborative knowledge development that supports a whole-of-system view, and transformational change at multiple scales. Such holistic urban approaches are rare in practice. A co-design process involving researchers, practitioners and other stakeholders, has progressed such an approach in the Australian context, aiming to also contribute to international knowledge development and sharing. This process has generated three outputs: (1) a shared framework to support more systematic knowledge development and use, (2) identification of barriers that create a gap between stated urban goals and actual practice, and (3) identification of strategic focal areas to address this gap. Developing integrated strategies at broader urban scales is seen as the most pressing need. The knowledge framework adopts a systems perspective that incorporates the many urban trade-offs and synergies revealed by a systems view. Broader implications are drawn for policy and decision makers, for researchers and for a shared forward agenda.

Australian cities rate high internationally on liveability and well-being indices. State and metropolitan governments are keen to promote the liveability of their cities as a means of attracting mobile capital, skilled labor, and tourists. An examination of the liveability-environmental sustainability nexus, however, suggests that Australia's capital cities have gained their high liveability ratings as a result of having inputs of high, and now unsustainable, levels of resource consumption—indirectly into their built environments and directly into their households. This paper explores the prospects for a socio-technical transition of key urban infrastructure systems—energy, water, waste, transport, communications and buildings—as a basis for winding back unsustainable levels of consumption while maintaining liveability.

Consumption is a transcending challenge for the 21st century that is stimulating research on multiple pathways required to deliver a more environmentally sustainable future. This paper is nested in what is a much larger field of research on sustainable consumption and reports on part of a major Australian Research Council study into the determinants of household resource consumption, based on a survey of 1,250 residents in Melbourne, Australia. Three environmental lifestyle segments are established that represent the spectrum of attitudes, opinions and intentions across the surveyed population: “committed” greens, “material” greens and “enviro-sceptics” (representing respectively 33.5%, 40.3% and 26.3% of the population). Each segment was found to display distinctive socio-demographic attributes, as well as urban geographies. However, few differences were found in relation to each segment’s actual consumption of energy, water, housing space, urban travel and domestic appliances. The research findings indicate that in these areas of urban resource consumption—all principal contributors to the ecological footprint of households—there are sets of factors at work that override attitudes, opinions and intentions as indicators of consumer behaviour. Some of these factors are information, organization and finance related and are the focus of much public policy. However, the persistence of well ingrained habits and practices among individuals and households and the lack of norms and values in western societies that explicitly promote environmental conservation among its population, are fundamentally involved in the attitude-action gap and constitute important avenues for future research and action.

Innovations capable of initiating a sustainability transformation of ageing suburbs in high-income Western cities are presented against a backdrop of urban infrastructures (housing, transport, water, energy) that are stressed due to levels of high population growth and consumption, an ageing asset base, changing socio-demographics, a resource- and carbon-constrained world, and an urbanizing world where attempts at urban intensification are confounding the urban planning and design professions. To be sustainable, cities need to be in a position to draw on innovative technologies, products and processes that can be substituted as existing infrastructures show signs of failure. A three-horizon model of urban technology innovation is proposed that is applicable at building, precinct and suburb scale. Cities also need to be innovative in the process of urban planning and design, especially in how they retrofit, redevelop, and regenerate their brownfield and greyfield precincts in the established inner and middle suburbs in order to encourage movement of population and investment inwards rather than outwards. New models of urban property redevelopment are required here to support greyfield precinct regeneration. The prospects for supply-side innovation are explored in the context of alternative urban infill approaches to regeneration in Australia's cities. Les innovations capables d'amorcer une transformation dans le sens de la durabilité des banlieues vieillissantes des villes occidentales à hauts revenus sont présentées dans un contexte d'infrastructures urbaines (logements, transports, eau, énergie) qui sont sursollicitées en raison des niveaux de forte croissance de la population et de forte consommation, d'actifs vieillissants, de données sociodémographiques en évolution, d'un monde soumis à des restrictions de ressources et d'émissions de carbone, et d'un monde qui s'urbanise dans lequel les tentatives d'intensification urbaine déconcertent les professionnels de l'urbanisme et de l'aménagement urbain. Pour qu'elles soient durables, il faut que les villes soient en mesure de recourir à des technologies, des produits et des processus innovants qui peuvent venir se substituer au moment même où les infrastructures existantes présentent des signes de défaillance. Il est proposé un modèle d'innovation technologique urbaine à trois horizons, qui est applicable à l'échelle du bâtiment, du quartier et de la banlieue. Les villes doivent également se montrer innovantes dans le processus d'urbanisme et d'aménagement urbain, en particulier dans la manière dont elles réaménagent, rénovent et régénèrent leurs quartiers de friches industrielles et de friches commerciales dans les proches et moyennes banlieues établies, afin de favoriser le déplacement de la population et des investissements vers l'intérieur plutôt que vers l'extérieur. De nouveaux modèles de rénovation de l'immobilier urbain sont ici nécessaires pour soutenir la régénération des quartiers de friches commerciales. Les perspectives d'innovation du côté de l'offre sont examinées dans le contexte des approches alternatives de la régénération, de type aménagement urbain intercalaire, dans les villes d'Australie. Mots clés: villes, friches commerciales, aménagement intercalaire, rénovation, banlieues, transitions, régénération urbaine, technologie urbaine

In the 21st century, the creation of built environments that are carbon neutral and water sensitive is critical for addressing sustainable urban development challenges. Both require transformative change: Decarbonisation to mitigate greenhouse gas emissions and incorporation of green-blue water sensitive solutions to adapt to climate change impacts. Transition pathways in both arenas involve combinations of new technology, innovative urban design, enabling policies and regulations, new processes for planning and managing urban development, and demand-side changes in consumer attitudes and practices for urban living related to energy and water use. In this paper, we present new knowledge, concepts and frameworks developed for application in Australia, as well as internationally, through research by the national Cooperative Research Centres for Low Carbon Living (CRCLCL) and Water Sensitive Cities (CRCWSC) between 2012 and 2020. These findings and outputs illustrate common features of the research strategies and initiatives that were central to the activities of the CRCs, and highlight promising directions for collaborative interdisciplinary and transdisciplinary research that drives urban sustainability transformations towards carbon neutral and blue-green cities.

Metropolitan planning and development of Australia’s cities for much of the past 75 years has been strongly influenced by what could be termed the “North American model” of low-density, car-dependent suburban development on greenfield master-planned housing estates. The negative social, economic and environmental consequences associated with perpetuating this low-density greenfield model were becoming evident by the 1990s and “compact city” policies began to feature, albeit in piecemeal fashion, in the long-term metropolitan planning strategies of the major capital cities in Australia. This compact city transition, from “suburban” to “urban” (i.e., from a low-density urban form dominated by detached housing with its own surrounding private space to one where there is a significant presence of medium-density and apartment accommodation), remains a challenging work in progress, as reflected in a rapid succession of metropolitan planning strategies—and reviews—for cities such as Melbourne and Sydney since the beginning of this century. Urban infill targets of 70% for new housing construction in these cities now represents a major break with the past and a challenge to the major stakeholders involved in urban development in Australia: state and local government, the property development industry and residents of the established, ageing “greyfield” suburbs that are a focus for intensified redevelopment. This paper comprises four parts. The introduction identifies the multiple challenges confronting 21st-century urban development in Australia. The second part frames transitions required for a regenerative retrofitting of the established suburbs of its major cities, with particular focus on the greyfields. The third section extends transition management research into an examination of the transformative capacity of each of the four key stakeholder groups that are central to achieving such a regenerative transition. To date, the greatest resistance to more intensive redevelopment has come from urban residents. The final section of the paper focuses on this stakeholder group, and draws on data from a major household survey that examines the attitudes of resident property owners in the middle suburbs of Sydney and Melbourne to neighborhood change and medium-density housing development.