Abstract: Social sustainability has become an important concept for Australian urban policy makers and scholars. Broadly defined, this involves a concern that cities and urban communities are able to be reproduced over time without inflicting unjust consequences on future inhabitants. The use of ‘sustainability’ in urban policy represents a significant migration for a concept that was popularized in 1987 by the global environmental issue focused Brundtland Report. However, given the lengthy influence of ecological thought on urban studies the concept’s recent adoption is perhaps not so surprising. Indeed, the concept certainly offers a valuable analytical perspective from which to examine and address a host of interconnected, contemporary urban policy issues. In this paper, the recent engagement by Australian urban scholars and policymakers with social sustainability is placed within the international context of European and North American urban policy debate. The paper begins by considering the possibility of a common set of neoliberal urban issues, such as social inequality, spatial segregation, rising housing costs and social tension. All of these are seen as challenges to making cities liveable, productive and, indeed, sustainable places. The paper then focuses upon a policy response to these issues which is common to Australia, the United States and the United Kingdom: the use of tenure and planning legislation to generate new neighbourhood social mixes. Drawing upon research based in the UK which examined the roll-out of such an approach, the impacts and effectiveness of social mix legislation are evaluated in terms of social sustainability. In conclusion, the paper reflects upon unfulfilled policy objectives and some potential solutions and research directions.