We argue that most of what passes for mainstream reporting in corporate sustainability management fails to do precisely the one thing it purports to do -which is make it possible for organizations to measure and report on the sustainability of their operations. It fails because of the lack of what the Global Reporting Initiative calls sustainability context, a shortcoming from which it, too, suffers. We suggest that this missing context calls for a new notion of sustainability (the binary perspective), which can be conceptualized in the form of sustainability quotients. We provide specifi cations for such quotients in ecological and social contexts, and suggest that sustainability is best understood in terms of the impact organizations can have on the carrying capacity of non-fi nancial capital, or what in the social case we call anthro capital. We conclude by introducing a quantitative quotientsbased method for measuring and reporting on the social sustainability of an organization, the social footprint method.