The importance of K-12 school leadership for student learning, teacher recruitment and retention, and school culture is well documented by research. Furthermore, there are compelling reasons for examining the connection between faith and educational leadership practice, a connection which should yield distinctive practices in faith-based schools. Unfortunately, little research has empirically examined principal preparation, particularly in the context of Christian schools. Using a nationally representative sample of 870 U.S. private and public high school principals, we examined how much training principals receive in seven areas of school leadership practice and where they received that training. We found that Protestant school principals receive similar amounts of training in areas like school law and personnel management but much less training in areas such as fiscal management and data-driven decision-making. We discussed the implications of our findings for Christian school leadership practice and principal preparation.