‘Knowledge transfer’ and ‘uptake’ are high on the agenda of government departments and research institutes. In the U.K., the Department for Environment, Food and Rural Affairs (DEFRA) is concerned that new knowledge generated by publicly funded research is not being taken up by the industry and has funded a series of knowledge transfer initiatives. On the international front, the Department for International Development (DFID) is pressing managers of its various research programmes to demonstrate that the outputs of research are being used by farmers in developing countries and are having an impact on their livelihoods. International institutes are increasing the proportion of their resources devoted to technology transfer and dissemination programmes. These concerns and initiatives raise important conceptual, institutional and methodological issues.