Historically, a sectoral approach (based on the industrial, transportation, commercial, and residential sectors) has shaped the way we frame and analyze issues of energy conservation and CO2 mitigation. This sectoral categorization, however, is limited in its capacity to reveal the total impacts of consumer activities on energy use and its related environmental impacts. In this paper, we propose an alternative paradigm, called the Consumer Lifestyle Approach (CLA), to explore the relationship between consumer activities and environmental impacts in the US. Estimates based on our methodology reveal that more than 80% of the energy used and the CO2 emitted in the US are a consequence of consumer demands and the economic activities to support these demands. Direct influences due to consumer activities (home energy use and personal travel) Lire 4% of the US GDP, but account for 28% and 41% of US energy use and CO2 emissions, respectively. Indirect influences (such as housing operations, transportation operations, food, and apparel) involve more than twice the direct energy use and CO2 emissions. Characterization of both direct and indirect energy use and emissions is critical to the design of more effective energy and CO2 emission policies. It may also help erode the false dichotomy of "them versus us" (industrial polluters versus consumers) references to the locus of responsibility for control of energy use and CO2 emissions. (C) 2003 Elsevier Ltd. All rights reserved.