Organizationally, what does not get measured is not prioritized or improved. Unlike student outcomes, the leadership environment that produces the results is rarely examined for its merit and impact. In this study, a quantitative survey gathered information to investigate the impacts of leadership capacity constructs on academic achievement. Principals from 161 public high schools and their schools provided the data (leadership capacity, demographics, and reading and math scores). Data were analyzed using descriptive, correlational, and regression statistics. Findings indicated significant high correlations among leadership capacity variables, significant relationships between school demographics (total school enrollment, percentage of low-income students, average class size, and attendance) and reading and math scores, and non-significant correlations between leadership capacity and academic achievement. The study delineated specific leadership capacity behaviors within the constructs that predicted student academic achievement in math and reading. The study suggests increased capacity and practice of these leadership behaviors to improve work setting and student achievement.