“In the 1970's and 1980's, ‘importing’ knowledge from other disciplines was common in tourism, today recycling the known knowledge has become the norm” (Jafari & McCabe, 2024). A recent review by McCabe (2024) found that tourism research has developed multiple discrete bodies of theory at various scales, on particular aspects such as destination image and tourist experience; but that despite decades of effort, there is no unified and comprehensive endogenous theory of tourism. We agree. McCabe concluded that tourism research should refocus on internal theory-building. This Commentary offers a counterpoint. We propose that the focus on internal theoretical mechanisms of tourism, whilst valuable historically, should now be supplemented by an enhanced emphasis on interdisciplinary and empirical analysis of tourism's external real-world roles. We argue that we should aim to demonstrate the broad importance of tourism research through increased citations in other disciplines and languages (Arenas-Castro et al., 2024; Correia et al., 2024; Wardle & Buckley, 2014).