There is a gap in our knowledge about environmentally conscious consumers in industrialized economies and the desire to achieve sustainable economies. Given that most aspects of consumer behaviour are culture bound, this paper contributes by comparing consumers' evaluations of the efficiency of actions to improve environmental quality in two of the most promising industrializing consumer societies: Brazil and China. The proposed conceptual framework includes environmental concerns, perceived consumer effectiveness, green attitudes, green behaviours and external motivators as constructs to explain the perception of efficient environmental support. Field research was conducted in Brazil with 1,149 respondents, and in China with 632 respondents to test the model. The results suggested that the belief that environmental quality can be improved is directly associated with consumers' internal and external motivators. However, cultural traits drove important differences in the evaluation of the efficiency of such improvements. Specifically, Chinese people tended to rely on collective leadership to create the conditions necessary for improving environmental quality, while they remained concerned with the current status. In contrast, Brazilians accepted more personal responsibility for the results, although they face important constraints, such as the availability of products. K E Y W O R D S environmental concerns, cross-cultural comparison, green attitudes, green behaviours, perceived consumer effectiveness