This article sets out to provide a general review of the basic principles of what is known as "methodological complementarity" in education research. Firstly, it addresses the context in which mixed methods have emerged to then go on to review some of the definitions. After reflecting on the advantages and limitations of these methods, several designs of mixed methods with examples drawn from education research and assessment are presented. The article concludes with an exposition of the discussion about the quality of the research conducted with a mixed method.
Keywords: Educational Research, Research paradigms, Methodological Complementarity, Mixed methods.