This paper draws on the authors’ experiences of nursing in general and of action research projects Parallels will be drawn between, on the one hand, the relationship between the practice and theory of nursing and, on the other hand, the relationship between the practice and theory of action research Difficulties common to nursing and action research will be identified (e g between the implementation of the theory of nursing and of action research) Oversimplification, non-specificity of issues and gaps in theory are frequent but inevitable problems that hinder theoretical applications Similarly, comparisons will be made between the problems associated with the translation of nursing practice into theory and the difficulties in transposing the experience of research into theory The complexities of practice, whether nursing or research, and the evolutionary nature of experience inescapably give rise to dilemmas when analysing theory and practice The concepts of theory and practice when conceived as a dichotomy present a useful overview of issues We argue that, through a discussion of the core themes of action research, including ‘knowledge in action’ and 'self and group reflection’, consideration should also be given to a symbiotic and complementary analysis of theory and practice We observe that many contradictions exist within the theory and practice of action research and of nursing, and that these need to be addressed to promote theoretical and practical advances Action research offers theoretical and practical insights that contribute to the current debate on the reciprocal relationship between theory and practice