There has been much discussion about quantitative and qualitative approaches to research in different disciplines. In the behavioural and social sciences, these two paradigms are compared to reveal their relative strengths and weaknesses. But the debate about both traditions has commonly taken place in academic books. It is hard to find an article that deals with the generic issues related to the quantitative and qualitative divide by drawing on distinguished research literature. Interested in addressing this need, this article aims to explain the essential characteristics of quantitative and qualitative research approaches with an emphasis on their underlying epistemological, theoretical, and methodological differences. It elucidates the research design issues and concepts in relation to both research paradigms, from planning research to collecting and analyzing data, and reporting findings. The criteria that are used to evaluate research strategies and findings are also discussed. (Contains 1 note and 4 tables.)