In this introductory editorial, we provide a brief overview of the history of individual difference research in leadership. We explain the major challenges that trait research faced, and why it was revived primarily because of methodological advancements. Next, we argue that leadership individual difference research is at a cusp of a renaissance. We explain why we are at this cusp and what researchers should do reify the renaissance in terms of theoretical extensions of trait models, the application of robust methodological advancements, and the development of process models linking distal (i.e., traits) predictors to proximal predictors (e.g., behaviors, skills, attitudes), and the latter to leader outcomes. We then summarize the papers we accepted for the special issue, and conclude with an optimistic note for leadership individual difference research.Keywords: leadership, traits, individual differences, personality, intelligence, multilevel models, process models. 3 The idea of a special issue on leader individual differences emerged following a symposium hosted in Lausanne, Switzerland on December 2009. From the discussions with the invited panel, presenters, and participants, the general consensus was that individual-differences research in leadership was at a critical juncture; a new genre of theories and the application of new methods would reignite interest in what has so far been a productive area of research with particular importance for practice.Our interest in editing this special issue was to provide a forum for new theory and novel findings on the general topic of leadership and individual differences both from a leader and a follower perspective. As all those who study individual differences know, this area of research has had a tumultuous history in general psychology (Kenrick & Funder, 1988;Mischel, 1977) as well as in leadership research (House & Aditya, 1997).At this time, there is still debate on what constitutes a trait (Jackson, Hill, & Roberts, 2012), whether personality is measured broadly enough (K. , 2008, whether big-five type inventories are casting too long a shadow over other individual differences that could also contribute to predicting outcomes (Day & Schleicher, 2006), and whether alternative conceptions of intelligence matter (Fiori & Antonakis, 2011).The notion of individual differences in leadership goes back a long way: The ancient Greeks took leader selection (as well as development) very seriously. For example, in the Republic (Plato & Jowett, 1901), Plato noted "we are not all alike; there are diversities of natures among us which are adapted to different occupations" (p. 50).With respect to leadership Plato said that: "There will be discovered to be some natures who ought to . . . be leaders in the State; and others who are not born to be [leaders], and are meant to be followers rather than leaders" (p. 175). He acknowledged that "The 4 selection [of leaders] will be no easy matter" (p. 56), and how right he was. This point is particularly salient nowadays, g...