This study outlines the relationship between teachers' and principals' perceptions of their influence over policies within their school and teachers' actual employment decisions--specifically, teachers' decisions to stay (continue their affiliation with their school), to move (transfer to a different school), or to leave the teaching profession. This article outlines a theoretical orientation that brings the exercise of influence within an organization together with three theories of school leadership to focus on the extent to which teachers' and principals' perceptions of their exercise of influence over school policy affects teachers' turnover decisions. Using data from the 1999-2000 Schools and Staffing Survey in a series of multinomial logistic regressions, the analysis finds that increases in teacher influence over school policy are associated with greater teacher job stability (stayers), whereas increases in principal influence over school policy are associated with a higher incidence of teachers leaving the teaching profession (leavers). This study highlights the important role that principals' perceptions of their own influence over school policy play in teachers' employment decisions and, therefore, the employment stability of teachers in their schools. (Contains 5 notes and 5 tables.)