Tourism and Sustainability. An Epistemological Reflection. The article makes an analysis of the main arguments and guidelines been followed by sustainable tourism as a legitimating ideology that justified and made viable the conventional model of tourism development, relegating the subjectivity of the individual as a principal actor in such a model. Thus it points out the importance of the subject and subjectivity in the meaning of sustainability with the possibility of gain the truth and put it into practice. This introduces a reflection on the construction of sustainability as an argument of instrumental reason in modern society based on the notion of crisis, which regenerates a capitalist production system of the State under their interests.