Humility in leadership has received growing scholarly attention in recent years. However, the literature is devoid of empirical studies of the relationship among humility, confidence (an attribute consistently linked to effective leadership), and leader effectiveness. This quantitative study examined the understudied relationships among these three constructs. In this study, 137 teachers from K-12 educational settings completed a survey measuring teachers' perceptions of their principals' confidence, humility, and leader effectiveness. Results showed that humility and confidence were strongly and positively related to each other and to leader effectiveness. The findings provide support for the importance of humility and confidence as attributes of effective leadership and have potentially important implications for educational leadership.