Many professions have long runways to leadership, with mentorship and increasing levels of responsibility. In contrast, the path to school leadership has historically not been well-defined. But that is changing. The role of assistant principals has become a major stepping stone to the principalship. Once thought of primarily as disciplinarians, assistant principals are now seen as key members of school leadership teams and an important part of building the principal pipeline. With responsibilities that include instructional leadership and professional learning, and with opportunities for close observation of and mentoring by principals, assistant principals are poised on a springboard to the next step. But making sure the dive off that board results in successful leadership and great student outcomes takes intentionality and support, at the individual level and a systemic one.