This chapter discusses the effects of social interaction on collective behavior regarding the reduction of limited-resource consumption. Our working hypothesis is that key societal and psychological mechanisms leading to sustainable lifestyles can be enabled by ICT tools. We envision tools supporting social norms, i.e. rules governing an individual's by social sanctions that encourage sustainable behavior on the part of user and consumers. As enabling technology we identify smart metering systems that allows users to compare their consumption patterns with the ones of other consumers, as well as to dynamically re-define and share their personal reduction goals. We present an Agent-Based Model (ABM) to explore the role of awareness in the consumption of a scarce resource. Our agents represent households that use a resource – e.g. energy or water – whose consumption has to be reduced. Agents influence each other; such influence improves their awareness that, in turn, impacts on resource consumption.