The goal of this study is to learn moreabout tourists’ understanding of sustainable tourism.The empirical survey with over 6,000 respondents ineight countries identifies the most relevant aspects ofsustainable tourism from a tourists’ perspective.Overall the perception is balanced over the differentdimensions. Furthermore, five different typesregarding tourists’ understanding of sustainabletourism are identified in a cluster analysis and apotential market size of sustainable tourism of 22%of all tourists can be identified