Despite a long history and considerable study, leadership remains a notoriously perplexing and enigmatic phenomenon. Although the "new leadership" perspective has revived convictions and general interest in leadership studies, conceptual and methodological problems nevertheless remain a feature of the research and theory-building terrain, and some voices now argue for more open and questioning approaches, or even abandonment of research in the area as fruitless and unproductive. Since research methods informing leadership studies are underwritten by particular epistemologies, which both furnish conceptual resources and impose constraints on theory building, theories of knowledge are critical to an understanding of the phenomenon. In specifying how learning occurs, and knowledge grows, epistemologies also imply theories of mind and cognition. Issues of knowledge, mind and cognition therefore clearly have a bearing on questions about leaders and leadership, with implications for the nature and direction of theorizing and research.