1 This is the accepted manuscript version of an article published in TESOL Quarterly. The published version is available via DOI: 10.1002/tesq.427. CITATION: Mirhosseini, S. A. (2018). Mixed methods research in TESOL: Procedures combined or epistemology confused? TESOL Quarterly, 52(2), 468–478. DOI: 10.1002/tesq.427 Mixed methods research in TESOL: Procedures combined or epistemology confused? Seyyed-Abdolhamid Mirhosseini Alzahra University, Tehran, Iran Email: mirhosseini@alzahra.ac.ir Abstract Mixed methods research tends to be received as a resolution to the traditional quantitative– qualitative debate in research methodology. However, although the extended repertoire of research techniques provided by combining the two approaches may appear practically attractive, the perspective of technical inclusiveness may raise questions at a deeper conceptual level. Revisiting aspects of mixed methods in TESOL research, this article focuses on the distinction of philosophical, methodological, and procedural concerns in academic inquiry. On this basis, I argue that in conceptualizing mixed methods, researchers may need to look beyond the simple combination of procedures and to consider more fundamental epistemological issues. While relying on a mix of numerical and verbal data might be helpful in gaining better understandings of complex language education problems, the crucial concern in this regard is epistemological rather than technical. It is about the level of mixing and the nature of knowledge that is sought, which cannot be both experimentally objective and subjectively constructed. Therefore, the TESOL research community may need to beware of an atmosphere of methodological discussions overshadowed by technicalities and to avoid the marginalization of epistemological understandings by emphasizing the quick-fixes of mixed methods. Introduction In a lunch-table chat on social science research, a senior colleague from the faculty of psychology asserted that mixed methods should be the optimum choice nowadays. Commenting on the quantitative–qualitative dichotomy, he categorized researchers who