This case provides an overview of the application of Discourse Theory. It outlines the underpinnings of Discourse Theory, including the constitutive role of ‘the political’, examines how data, or ‘text’, are defined in Discourse Theory and explores how it may be usefully applied in the context of an empirical research project involving multiple data sources. Employing an example from an interdisciplinary research project, I demonstrate the applicability of Discourse Theory in examining the hegemonic articulation of the subject position, the contagious immigrant, in Sydney, Australia, as it relates to tuberculosis (TB) and HIV. The project draws on an analysis of a range of ‘texts’, including legislation, legal judgements, policy documents, as well as print media articles. The collection, analysis and presentation of ‘text’ within a Discourse Theory approach are critically discussed, particularly in relation to traditional approaches to social research.