Abstract
This article presents a grounded theory to explain why some small businesses in tourism adopt sustainable business practices while others do not, even when they share environmental and wider sustainability concerns. It does so based on research undertaken among business owners in Crete. The paper starts by considering studies on sustainability awareness, knowledge and the mechanisms for accepting responsibility. Secondly, it summarises the influence of task difficulty and effort on sustainability self-efficacy. Thirdly, it focuses on social comparisons and vicarious experiences, as a way of learning what is important. Finally, it examines powerlessness due to perceived situational constraints. In so doing, the study finds that self-efficacy helps to explain sustainable attitude formation and the attitude-behaviour gap; it partly shifts the locus of responsibility for an inability to act sustainably away from the individual and towards their context. The paper contributes to the theoretical literature on small businesses and sustainability, and leads to new avenues for policy interventions.