Purposes: This study aimed to improve our understanding of the nature, causes and consequence of school leader efficacy, including indirect influences on student learning. We asked about district contributions to school leader efficacy, whether leader self- and collective efficacy responded to the same or different district conditions and the effects of leader efficacy on conditions in the school and the learning of students. Methods: Evidence for the study was provided by 96 principal and 2,764 teacher respondents to two separate surveys, along with student achievement data in language and math averaged over 3 years. Path analytic techniques were used to address the objectives for the study. Findings: In this study, school leaders' collective efficacy was an important link between district conditions and both the conditions found in schools and their effects on student achievement. School leaders' sense of collective efficacy also had a strong, positive, relationship with leadership practices found to be effective in earlier studies. Implications: These results suggest that district leaders are most likely to build the confidence and sense of collective efficacy among principals by emphasizing the priority they attach to achievement and instruction, providing targeted and phased focus for school improvement efforts and by building cooperative working relationships with schools. (Contains 8 tables, 1 figure, and 2 notes.)