Research has confirmed that leader behavior influences group and organizational behavior, but we know less about how senior leaders ensure that group and organizational members implement their decisions. Most organizations have multiple layers of leaders, implying that any single leader does not lead in isolation. We focused on how the consistency of leadership effectiveness across hierarchical levels influenced the implementation of a strategic initiative in a large health care system. We found that it was only when leaders’ effectiveness at different levels was considered in the aggregate that significant performance improvement occurred. We discuss the implications of these findings for leadership research, specifically, that leaders at various levels should be considered collectively to understand how leadership influences employee performance.