Urban environmental sustainability assessment is increasingly a part of urban planning, from the perspective of mitigating local and global impacts and for adapting to regional and global resource constraints and anticipated climate events. We examine general techniques under three categories: consumption-based, metabolism-based and complex systems approaches. We sample recent and salient applications at spatial scales ranging from neighbourhoods to metropolitan regions. The scope and strengths of applications in these categories are complementary especially with regards to the attribution of impact. The first approach assesses environmental sustainability as a function of urban consumption, the second uses a more limited concept of consumption but better represents local and trans-boundary production activity and the third attributes cause and effect through quantifying relationships and feedbacks throughout the urban system.