The paper contains considerations on the issue of sustainable consumption whose stimulator may be consumer competences. The problem can be examined in the cognitive, emotional and behavioural dimensions. Besides the theoretical approach, the authors have presented findings of the research carried out for the purposes of the project “Consumer Competences as a Stimulant of Innovative Behaviours and Sustainable Consumption” (2011/03/B/HS4/04417) financed from resources provided by the National Science Centre. The research involved a research sample of 1,000 Poles meeting specific criteria established by the authors. The obtained empirical material allowed for the construction of the consumer competence index which took into account the following variables: Knowledge of the consumer’s rights and ways of use thereof (Knowledge), Planning measured with the following variables (Planning), Making rational consumption choices measured with the following variables (Rationality), Autonomy of choices measured with the following variables (Sovereignty). Three groups of consumers were singled out and characterised in the study, namely: highly competent consumers, consumers with a medium level of competences, and consumers with low competences.