This article extends social psychological research on the motivations for sustainable consumption from the predominant domain of ecologically conscious consumer behaviour to socially conscious and frugal consumer behaviours. A UK-based survey study examines relationships between socially conscious and frugal consumer behaviours and Schwartz's value types, personal and socio-political materialism, and demographics among the general public. Socially conscious consumer behaviour, like its ecological counterpart, appears to be an expression of pro-social values. In contrast, frugal consumer behaviour relates primarily to low personal materialism and income constraints. As such, it does not yet represent a fully developed moral challenge to consumerism.