This paper reports on an analysis of English research article introductions written by English native speaking authors and Korean authors, using Swales` (1990) Create A Research Space (CARS) model. Data analysis leads to a modified version of the CARS model. The results of the analysis based on the revised one reveal that the NS and the NNS authors employ slightly but certainly different rhetorical strategies in writing research article introductions, which has pedagogical implications. Compared to the NS authors, the Korean authors are seen to employ the strategies of "claiming centrality" and "continuing tradition" slightly more often. The Korean authors justify their research by stating "a problem in the real world" more often and summarize principal findings less often.