The author considers the claim that the nature and merits of both action research and communities of practice are contested. The author describes three strands of argument. Firstly, action research is not necessarily a contradiction in terms. Secondly, communities of practice are not necessarily the end of educational research as a discipline in its own right. Thirdly, however, Hammersley’s critique raises important issues about professional knowledge development, inviting interaction between propositional and workplace knowledge.