Open AccessThe term ‘sustainable’ has rapidly become a ubiquitous prefix for many contemporary issues, subjects, professions and disciplines. This paper contextualizes the debate by exploring how the term ‘sustainable’ has emerged within the field of architecture. The paper examines the semiotics of sustainability; how the meaning of this word has been produced from an assemblage of words, signs and practices. Adopting‘Actor-Network Theory’ (ANT) methodology to examine the embedding of sustainability as the dominant paradigm in architecture. The creation of a definition of sustainability has been hybridized into a social, legal, economic, political and scientific framework. A process of ‘sustainabilization’ has occurred not only within architecture but across a number of different subjects. The research investigates how Carbon-dioxide has played an important role in the promulgation of sustainability. The current framework within which ‘sustainability’ operates is currently too narrow and inflexible (i.e. black-boxed) with too much emphasis on CO2.