Principals are a key in-school factor associated with student achievement. When principals leave, it can disrupt school progress, increase teacher turnover, and stall student achievement. The Learning Policy Institute and the National Association of Secondary School Principals engaged in a joint project to increase awareness of this issue and identify and share evidence-based responses to help mitigate excessive turnover in the principal profession. The project involved research into the causes and consequences of principal turnover and developing policy recommendations to stem that turnover.