In increasing numbers of individual schools across the country, a new kind of principalship is taking hold and producing well-documented breakthrough results for children. This executive summary presents the highlights of a report that uses findings from these schools and principals to inform a new definition of principal effectiveness. This report makes recommendations for school leadership policies geared toward dramatically increasing the number of successful principals. These recommendations will contribute substantially to scalable improvements in both teacher effectiveness and the ability to turn around the nation's lowest-achieving schools. (Contains 10 endnotes.) [For the full report, "Principal Effectiveness: A New Principalship to Drive Student Achievement, Teacher Effectiveness and School Turnarounds with Key Insights from the Urban Excellence Framework[TM]," see ED532064.]