The issue of the relationship between educational research and policy making or practice has been a perennial concern. In Educational Research Martyn Hammersley deals with some basic and controversial assumptions about research and practice, including: * is there always conflict in the relationship between research and practice? * do increases in knowledge really lead to practical improvement? * is a review of research likely to be objective? * what effect does mass media involvement have in communicating the results of research? The author addresses the demands now being made on educational research against the background of the complex relationship between research and practice.