School leadership turns over frequently. Superintendent succession is well-documented, particularly in urban areas, where average tenure is about 5.5 years (The Broad Center, 2018). In 2015-16, 16% of public school principals left their jobs, with most of them leaving the principalship altogether (Goldring, Taie, & O’Rear, 2018). These patterns are discussed often and with some concern. Less often discussed, however, are the career trajectories of assistant principals or vice principals. There is little research on how often they change schools or are promoted to full campus leadership. Such changes could be destabilizing — but they could also be positive. If assistant principals are intentionally and thoughtfully prepared for the principalship, they could help fill the gaps created by principal attrition, and perhaps even stem the