Individual differences in the preference for group-based hierarchy and inequality, as indexed by social dominance orientation (SDO), have been shown to predict environment-relevant variables. To date the literature examining the SDO–environmentalism link has used the traditional unidimensional conceptualisation of SDO. This article reports three studies using the new measurement and conceptualisation of SDO that involves the SDO7 scale and the sub-dimensions of intergroup dominance (SDO-D) and intergroup anti-egalitarianism (SDO-E). SDO-D entails support for group-based dominance achieved via overt oppression and aggressive intergroup behaviour, and SDO-E entails support for group-based inequality subtly achieved via unequal distribution of resources. Our results show anti-egalitarianism to be the main SDO sub-dimension related to environmentalism. While SDO-D is either a weaker or non-significant predictor, individuals with high levels of SDO-E were less willing to make personal sacrifices for the environment, value environmental protection and endorse climate change beliefs. Interestingly, neither facet of SDO predicted change in environmentalism over a five-month period; but climate change denial predicted change in SDO-E while pro-environmental attitudes predicted change in SDO-D over time.