This chapter seeks to situate sustainability within particular epistemological fields and communities in order to understand the growing contentiousness between rival versions of the concept. Focusing on the famously green yet increasingly unaffordable 'luxury city' of San Francisco Bay Area, it explores how these epistemological formations are quite literally 'situated' geographically, shaped by and shaping of the places, communities, social relations and political ecologies in which they emerge. It argues that as investments into greening are increasingly designed to serve powerful economic actors in aspiring global cities and regions like San Francisco, prevailing, historically and culturally rooted understandings of sustainability are often reframed and redefined in a more instrumentalist, market-oriented direction. The latter approach comes into conflict with classic understandings of the “3 E’s” of sustainability—in which economic concerns are balanced with and equal to those of equity and ecology. And they pose fundamental questions about what and how environmental justice politics are to be practiced today. The chapter aims to contribute to such emergent politics and scholarship by advancing a critical approach to "sustainability" that takes seriously the role of power, place, and history in shaping our use of the term.