We explore the role of leader personality (i.e., the Big 5 traits: Conscientiousness, Agreeableness, Openness, Extraversion, and Neuroticism) and gender in self–other (dis)agreement (SOA) in ratings of leadership. We contend that certain aspects of the leader's persona may be more or less related to self- or other-ratings of the leader's behaviour if those aspects are (1) more or less observable by others, (2) more or less related to internal thoughts versus external behaviours, (3) more or less prone to self-enhancement or self-denigrating biases, or (4) more or less socially desirable. We utilize statistical methodologies that capture fully the effects of multiple independent variables on the congruence between two dependent variables (Edwards, 1995, Organizational Behavior and Human Decision Processes, 64, 307), which previously have not been applied to this area of research. Our results support hypotheses predicting less SOA as leader Conscientiousness increases and greater SOA as Agreeableness and Neuroticism increase. Additionally, we found gender to be an important factor in SOA; female leaders exhibited greater SOA than did their male counterparts. We discuss the implications of these findings, limitations, and future research directions.