Currently, many districts and states are pursuing reforms that focus on holding principals accountable for school performance. While effective schools research has established that strong principal leadership affects school academic achievement at least indirectly, this relationship is more complex than originally thought. Personnel decisions about principal effectiveness made by educational policymakers or lay-controlled school site councils should be made only after careful consideration of research on the relationship between principal instructional leadership and school outcomes. This article presents data from a study to determine whether principal instructional leadership is predictive of school outcomes and discusses the implications of the research for developing school improvement strategies.