In light of the recognition that current patterns of consumption in the developed world are environmentally damaging, the question of sustainable consumption has become increasingly prominent in public and policy discourse. This paper joins an emerging body of work that critiques the behaviorist perspectives that currently dominate the field and specifically, a case is made for using conventions theory (Boltanski and Thevenot, 1991) to complement the "social practices" approach to consumption, sustainability and everyday life. Drawing on a qualitative study of persons who identified themselves as attempting to live in ways that are environmentally more friendly, the analysis first explores the ways in which sustainable consumption intersects and overlaps with other practices and imperatives. Attention is paid to the competing demands of day to day living and the ways in which cultural conventions work--or not--to legitimate practices of sustainable consumption. The second part of the analysis discusses the citizenship relations that are articulated through practices of sustainable consumption and here, attention is paid to the conventions that underpin the imperative to reduce the environmental impacts of personal consumption. Taken together, I consider the possibility that environmental conventions might be emerging from the empirical material alongside the ways in which these might operate in support of sustainable consumption. To conclude I suggest that the experiments in practice encountered here are unlikely to generate the conventions through which sustainable forms of consumption can be normalized and integrated into everyday lives. (Contains 1 table.)