Past empirical studies relating narcissism to leadership have offered mixed results. This study integrates prior research findings via meta-analysis to make four contributions to theory on narcissism and leadership, by (a) distinguishing between leadership emergence and leadership effectiveness, to reveal that narcissism displays a positive relationship with leadership emergence, but no relationship with leadership effectiveness; (b) showing narcissism's positive effect on leadership emergence can be explained by leader extraversion; (c) demonstrating that whereas observerreported leadership effectiveness ratings (e.g., supervisor-report, subordinate-report, and peer-report) are not related to narcissism, self-reported leadership effectiveness ratings are positively related to narcissism; and (d) illustrating that the nil linear relationship between narcissism and leadership effectiveness masks an underlying curvilinear trend, advancing the idea that there exists an optimal, midrange level of leader narcissism.During the last decade, organizational researchers have become increasingly interested in narcissism, as recently evidenced by several insightful contributions (e.g., Galvin, Waldman, & Balthazard, 2010;Judge, LePine, & Rich, 2006;Judge, Piccolo, & Kosalka, 2009;Nevicka, Ten Velden, De Hoogh, & Van Vianen, 2011;Peterson, Galvin, & Lange, 2012), digitalcommons.unl.edu 2 G r i j a lva , H a r m s , N e w m a N , G a d d i s & F r a l e y i N P e r s o n n e l P s y c h o l o g y 6 8 ( 2 0 1 5 ) including a meta-analysis of narcissism and work performance (O'Boyle, Forsyth, Banks, & McDaniel, 2012). Narcissism's rise in popularity coincides with a larger trend in the field of organizational psychology toward building a more thorough understanding of negative workplace behaviors (e.g., counterproductive work behaviors [CWB], abusive supervision, and incivility; Andersson & Pearson, 1999;Sackett, 2002;Tepper, 2000). Within this context, negative personality traits have a newfound appeal, as they carry the potential to harness validity left untapped by trait paradigms focused on the more positive side of personality (Grijalva & Newman, in press;Hogan & Hogan, 2001;Judge et al., 2006;O'Boyle et al., 2012;Paulhus & Williams, 2002;Penney & Spector, 2002;Wu & LeBreton, 2011).This paper seeks to integrate and extend existing findings regarding narcissism's impact on leadership. To be clear, much existing research already focuses on narcissism's role in leadership (Kets de Vries & Miller, 1985;Maccoby, 2000;Rosenthal & Pittinsky, 2006); but this research has not produced consensus concerning whether narcissistic leaders hinder or benefit their organizations. To begin clarifying this issue, we first note that researchers typically define narcissism by listing several diagnostic criteria for Narcissistic Personality Disorder from the Diagnostic and Statistical Manual of Mental Disorder-IV (DSM-IV; APA, 2000; e.g., "has a grandiose sense of self-importance"; "requires excessive admiration"; "has a sense of entitl...