Research Article (RA), in particular, its structure, social construction and historical evolution, has been focused upon through a large number of studies on academic writing over the past 20 years. This paper reports an analysis of research article introductions from three related fields, English for Specific Purposes (ESP), Psycholinguistics, and Sociolinguistics, using Swales’ CARS model. The corpus consisted of 90 RAs drawn from a wide range of refereed journals in the corresponding disciplines. The results of the analysis, although revealing marked differences across the disciplines regarding Move 2/step 1B, indicate no marked differences in research article introductions across the disciplines in terms of Move 1 and 3 along with their constituent steps. Furthermore, no marked differences are found in terms of the extent of concordance between the CARS model and the move structure of the RAs analyzed. The results also underline the need for further research into the CARS model and provision of a more flexible and open-ended structure, one which is pattern-seeking rather than pattern-imposing and provides the writer/researcher with the necessary options for the inclusion of further steps, one in which free-standing steps are not assigned rigid functions and positions in the overall structure but are multi-functional or multi-purpose and can be shuffled in the overall structure.