This paper analyses urban densification in Norway as a key element of sustainable city policies. The city is viewed as a system in which changes of material aspects, such as density, are linked with social and technological aspects. Densification targets in Trondheim are used as a case study to explore the main actors and factors involved in urban development. A multilevel perspective approach used in sustainability transitions studies is applied as a model to describe them. The aim is to illustrate interactions and barriers arising in the implementation of densification policies. The argument suggests that despite a shift of paradigm in planning towards sustainability, urban regimes have remained rather stable. Some progress has been made, but further advancing the sustainability agenda may require new rules in the regime -for example, new planning policies integrated with taxation and financial instruments, and transport regulations -and a stronger emphasis on niche developments.

Compact settlements take advantage of economies of scale by sustaining a system of high-quality socio-economic services at close proximities. Urban density with a balanced mix of uses also benefits walking and cycling as mobility modes that provide sufficient access to urban amenities, especially when combined with effective public transport. Indeed, walking and cycling can decrease the use of cars for short-distance trips. From this perspective, urban density can help to reduce pollution, optimise energy consumption and decrease infrastructural expenditures while contributing to more attractive urban environments. These ideas have induced a new wave of time geography planning concepts, such as the ‘10-minute city’, to enhance urban sustainability. For these concepts to move beyond visionary narratives, they must be expressed in specific empirical frameworks. Thus, the current research focuses on accessibility to grocery shops, as an essential urban service, in the Stavanger metropolitan area (Norway) using 10 minutes isochrones for walking and cycling. The study integrates open data, GIS network analyses, statistical regressions and bivariate representations of the results. The research estimates the level of serviceability by quantifying the number of shops that are accessible for each location and interrelates this estimation with spatial and population densities. The paper also presents a method to detect spatial inequalities by visualising over/under-serviced areas. This visualisation can become a tool to support strategies to rebalance such imbalances. Moreover, this study offers a practical approach towards the ‘10-minute city’ concept, as it can be adjusted to different isochrones at different spatial scales. In general, this approach can serve both to analyse existing contexts and to model strategies to support sustainability policies, such as urban densification and the promotion of environmental-friendly transport.

Increasing urban density has been regarded as one of the key strategies to achieve sustainable urban ways of living. The compact city has become the paradigm of the sustainable urban form particularly because of its contribution to environmentally friendly mobility and the decrease of the carbon footprint. Density has also been a precondition to many of the qualities of the 'good city' in the tradition of architecture, urban design, and planning, long before the emergence of the concept of the sustainable city. This former ideal can be closely related to the principles behind the sustainable city, and can be a highly relevant contribution to the materialisation of sustainable built environments. The question addressed in this paper is how density can contribute to the ideal of the 'good city', since this quality is a key component of the Norwegian sustainable city policy. This paper analyses density as a key component of the concept of urban quality through a comprehensive literature review. The findings indicate that urban density was a key component of the ideal of the 'good city' long before the emergence of urban sustainability. Density has been incorporated later as an essential characteristic of the Norwegian sustainable city policy. Increasing density, however, may have two kinds of risk: the first is the decline of urban quality and its consequences in people's quality of life, and the second is the increase of gentrification and the exacerbation of social inequalities.