This article proposes a (critical) realist agenda for tourist studies, centred around the question, ‘What makes tourism possible?’. In asserting realism as the philosophy of social science most likely to advance tourism theory, it offers a critique of prevailing epistemologies, notably positivism and constructivism (and critical theory), with a view to provoking engagement by the tourism research community with ontological and epistemological arguments, which we would contend is the hallmark of a mature subject area that is not derivative of disciplines. In the furtherance of this cause a critical assessment is made of the ontological, epistemological and methodological assumptions underpinning an idea or assemblage of ideas within tourist ...