Social sustainability is a multidimensional concept sensitive to the contexts of its application. This study explores how it is interpreted and applied in urban planning practices in which general social sustainability goals are translated into specific urban design interventions. Building upon Sen’s Capability Approach (CA), we analyse the gap between the operationalization of social sustainability goals in Urban Development Projects (UDPs) from the perspective of urban planners, and the following experiences of the residents in the developed urban areas. By applying a capability-based evaluative framework to a UDP in Amsterdam, the study reveals that residents value distinct urban functionings and experience different enabling factors related to urban social sustainability. We conclude that the CA provides an operationalizable framework for assessing how social sustainability goals defined at the early stage of UDPs translate in the actual capabilities of the urban residents for whom those very goals were conceived.

In Europe, growing concerns about social segregation and social stability have pushed calls to make cities ‘inclusive, safe, resilient and sustainable’ higher on policy agendas. However, how to approach such generic policy objectives and operationalise them for planning practices is still largely unclear. This article makes a conceptual contribution to the operational understanding of social sustainability in urban planning practices. The article argues that, between theoretical concept and operational forms, different evaluative approaches towards social sustainability may be taken. Evaluating three dimensions of policy operationalisations in The Netherlands, we argue that Amartya Sen’s capability approach provides a promising conceptual framework for operationalising social sustainability in cities in Europe and beyond. We compare capabilities with a more commonly applied resource-based conception to show that the former is more accurate and potentially more effective, because it shifts the evaluative space of social sustainability from means (i.e., urban resources) to ends: the eventual well-being of urban citizens.

Social sustainability’s implementation in urban development is a complex endeavour that demands alternative forms of governance. This article draws on the capabilities approach as an evaluative framework to better understand this implementation process. Through an in-depth case comparison of two Dutch urban development projects, the study analyses how collaborative governance situations (i.e. actors, activities and phases) relate to the expansions of resident capabilities in the urban areas. The findings present three principles for a ‘capability-centred governance’ of social sustainability in urban development: (1) integrate human logic into urban governance situations (2) balance strong goal commitment with experimentalist approaches and (3) institutionalise social sustainability implementation. The article concludes that social sustainability’s implementation requires a conceptualisation in which improvements in people’s lives are not seen as the self-evident consequences of a set of place-based policy interventions, but instead as a guiding principle that should continuously be reflected upon and learned from during the different phases of urban development processes.