The term `sustainable consumption' denotes the search for consumption patterns that reduce human pressure on the environment and nature. This searchinvolves three levels of research. First, the relationship between consumption, lifestyles and environmental sustainability has to be clarified. Ageneral scheme of relationships will be presented here. Second, a theoretical framework for studying economic behaviour, consisting of five elements, is proposed. Moreover, various theoretical models are discussed in this context. Finally, the policy relevance of specific theories of behaviour forsustainable consumption is considered. This gives rise to both traditional and innovative prescriptions.