Since the Brundtland Report, sustainable development has been established as a central norm within urban development practice, with sustainable urban development often treated as an almost self-evident objective for contemporary urbanisation, where environmental protection, economic growth, and social welfare are combined within a shared policy agenda. This self-evidence can, however, be understood as an expression of common sense—assumptions that appear universal and uncontroversial, but which are in fact historically and geographically situated and shaped by specific power and knowledge relations. In practice, this implies that sustainable urban development does not constitute a unified concept, but rather a complex, mutable, and often conflictual process that is continuously reconfigured across different socio-material contexts.Despite this acknowledged complexity, sustainable urban development has been criticised for being operationalised through a discourse of ecological modernisation, in which technological innovation and resource efficiency are expected to enable continued economic growth without compromising the needs of future generations. This pragmatic policy logic has contributed to a depoliticisation of the sustainability issue by downplaying conflicts between social, economic, and ecological justice and growth-oriented market logics. As a result, sustainability risks reproducing prevailing urbanisation trajectories rather than transforming them. In this sense, sustainable urban development projects can be understood as a sustainability fix, where an explicitly sustainable planning practice legitimises a continued urban development practice that does not substantially differ from dominant urbanisation practices.In the Swedish context, this practice has evolved through a long tradition of working with sustainable urban development, where Sweden has positioned itself as an international forerunner, with a large number of ambitious projects and several national strategies aimed at strengthening innovation, collaboration, and local capacity for sustainable development. A central component of this agenda has been the development of sustainable neighbourhoods, where projects function as experimental environments for testing new technical, social, and planning solutions. Several flagship projects in metropolitan regions have received considerable attention and have circulated within planning and policy discourses as best-practice examples of sustainable urban development.This dominance of metropolitan-based examples has, however, contributed to a knowledge gap regarding sustainable urban development in more peripheral and peri-urban environments. Peri-urbanisation describes a contemporary pattern of urbanisation in which central and peripheral urban characteristics are intertwined in heterogeneous and fragmented landscapes characterised by in-betweenness. These environments are not the outcome of prevailing planning ideals, but rather of unplanned processes emerging as spatial and functional structures expand. While peri-urban environments have often been marginalised within both research and planning practice, they today constitute central arenas for contemporary urbanisation and thereby potential sites for innovation and transformation.Against this background, the thesis aims to examine what happens when the concept of sustainable neighbourhoods is mobilised to peri-urban contexts. The focus is on the spatial, institutional, and conceptual reconfigurations that emerge when policies, practices, and ideas are translated across contexts. The thesis draws on theories of policy mobility, which emphasise that urban policies do not circulate as fixed entities but are transformed through processes of translation, mutation, and reconfiguration. This perspective enables an analysis of how sustainable urban development is constituted through a dialectical interplay between dominant discursive articulations and local conditions within the situated context.Theoretically, the study is grounded in a post-structuralist and relational tradition, where space is understood as assemblages—dynamic configurations of socio-material relations in continuous processes of becoming. In combination with critical urban theory, this highlights how the mobilisation of urban policy discourses can function as hegemonic interventions that reproduce unevendevelopment and prevailing power relations, while the contingency of spatial and discursive configurations simultaneously opens up possibilities for counter-hegemonic articulations and alternative development trajectories. The thesis also integrates literature on place-based development, social innovation, and transformative innovation policy to explore how sustainable transformations can be contextually grounded in local conditions rather than scaled from previous examples.Empirically, these questions are examined through an analysis of planning documents for sustainable neighbourhood development in Sweden, as well as an in-depth case study of Jakobsdalen in Borlänge—a project that represents the mobilisation of sustainable neighbourhood development in a peri-urban context. Borlänge, with its industrial history and experience of territorial stigmatisation, provides an illustrative case of how sustainability discourses are mobilised to reconfigure place identity in order to enhance attractiveness. The case study thus enables an analysis of both the possibilities and challenges associated with sustainable neighbourhood development in contexts characterised by peripheralisation and complex socio-spatial configurations.The overarching aim of the thesis is to problematise how sustainable neighbourhoods are conceptualised and mobilised within planning and policy discourses, and to identify the implications of this for peri-urban environments. The study also seeks to explore possibilities for the emergence of more context-sensitive and transformative practices by developing and testing a designerly approach in which sustainable urban development is treated as a boundary object. This approach aims to enable shared processes of interpretation between actors and contextual conditions, thereby organising and opening up for transformative and innovative solutions adapted to situated contexts.Through this approach, the thesis contributes to a deeper understanding of sustainable urban development as a relational and situated practice. It demonstrates how dominant urban articulations of sustainability risk reproducing prevailing development trajectories while simultaneously constraining the translation of policies across contexts. The thesis shows how this generates significant challenges for sustainable urban development in peri-urban environments. At the same time, it highlights the potential of these environments as sites for innovation and transformation, where contextual dynamics can be mobilised as resources rather than constraints. The thesis therefore argues for the need for a more pluralistic and context-sensitivemobilisation of sustainable urban development that recognises diversity and opens up for alternative urbanisation practices.