Leaders' efforts at shaping people's convictions are vital to the effectiveness of formal and informal organizations (Hambrick, 2004;Whittington, 2003). Unfortunately, the domains of strategy and organization theory have been ignoring the critical role of leadership -a concept that may both enlighten and help bridge the two domains. In strategy, the emphasis has been largely on economically rational behaviour, competitive positioning, and resources and capabilities. In organization theory, the focus has been on macro-social levels of analysis and on structural parameters. In each domain there has been too little attention paid to the micro-processes of individual human interaction in which beliefs and values -indeed convictions -are transferred among people within an organization: a process that is at the heart of developing and implementing strategy, and a central contributor to, and outcome of organization design. We shall argue this process to be, in essence, leadership.One possible reason for the neglect of leadership in strategic organization is that we lack a robust concept of it that would be useful to scholars in this domain. Certainly, there have been thousands of studies of leadership, and the term has enjoyed a wide range of definitions and conceptions (Bass, 2008;Yukl, 2006). In fact, Bass's Handbook of Leadership contains about 10,000 references! However, the concept of leadership is sometimes cast too broadly to have clear implications for organizational behaviour, or too narrowly to do it justice in the many management situations in which it occurs (Podolny et al., 2010). That may limit its usefulness.The objective of this essay is to provide an appropriate concept of leadership for scholars of strategy and organization and to suggest its research implications. First we relate why most current notions of leadership are unable to capture fully its significance for the study of strategic organization. Then we propose a baseline conception of leadership whose parameters are promising for that purpose. We also investigate the boundaries of the term to appreciate its varieties. We conclude with the implications our conception of leadership has for addressing gaps in the literature on strategy and organization, and suggest several research directions.