This article focuses on similarities and differences between some key approaches to action research. The aim is to investigate perspectives, principles and dilemmas concerning the purpose of action research, development methods, the role of the researcher and the epistemological basis. The analysis sheds light on important dilemmas to which there are various answers. There are different views on the extent to which the purpose of action research is to develop and document knowledge for practitioners or for academia. A major methodological challenge is about the distribution of power and balance between participant influence and research management. An important dilemma is whether the researcher should be internal or external in relation to the context in question. One important epistemological issue concerns the potential of action research to transcend established traditions and structures. Another is whether democratic participation is an end in itself. A common core is to create value-conscious, practically relevant research through collaboration in social and professional fields.