Education decision makers in Colorado, Missouri, and South Dakota share concerns about mobility and attrition among school and district leaders. In collaboration with educators in these states, the Regional Educational Laboratory Central used administrative data to examine the percentages of school and district leaders who remained in a leadership position in the same school or district (retention/stayers), who transferred to a leadership position in a different school or district (mobility/movers), and who took a nonleadership position or left the state public school system (attrition/leavers). The study also examined the characteristics of principals, schools, and districts that were associated with principal mobility and attrition. The findings focus on one-year (2017/18 to 2018/19) and three-year (2015/16 to 2018/19) periods and provide region-specific and state-specific information about school and district leader retention, mobility, and attrition. Findings may be used to inform the design of policy and practices focused on attracting and retaining school and district leaders. [For the full report, see ED607378; for the appendixes, see ED607379; and for the study brief, see ED607380.]