This paper focuses on the role of research in the improvement of educational practice. I use the "10 Principles for Effective Pedagogy," which were formulated on the basis of research conducted in the UK's Teacher and Learning Research Programme as an example to highlight some common problems in the discussion about research and educational improvement. In the paper I explore three issues. The first concerns the idea that the improvement of education is identical to increasing the effectiveness of educational action. Here I suggest that in education the question is never whether something is effective or not, but what something is supposed to be effective for, which is the question of educational purpose. The second issue concerns the prevalence of quasi-causal thinking about educational practice and its improvement. Here I suggest that complexity theory and the idea of complexity reduction provides a much more meaningful educational ontology that makes it possible to think very differently about the drivers for educational change and improvement. Third, I make a distinction between two ways in which research knowledge can be meaningful and useful for educational practice--a technical way where research is supposed to generate knowledge about how to do things and a cultural way which has to do with generating different ways to make sense of education. Seeing that research can engage with educational practice in these two different registers, opens up a different way to think about what research might aim to achieve in order to contribute to educational improvement.