It is critical that education researchers, policymakers, and practitioners address the persistent challenge of how to effectively jump start improvement in our nation’s poorest performing schools as many systematically fail, year after year, to meet the needs of large numbers of students (U.S. Department of Education, 2010). However the education field must also not lose sight of a related but equally important problem – how to sustain student achievement gains and a trajectory of school improvement over time (Datnow, 2005; Hargreaves & Fink, 2003; Maden, 2001). This study addresses the need for more empirical research on the sustainability of school improvement by returning to two successful Vermont elementary schools initially profiled in the Roots of Success (Hayes, 2009) report to determine whether they have been able to maintain their record of improvement as well as explore the various factors, forces, and influences that have impacted the sustainability of their student achievement gains. Findings suggest that a complex web of interrelated factors including stable and distributed leadership, a clear organizational mission and culture focused on continuous improvement, and a connected and collaborative staff help schools sustain progress over time and navigate difficult conditions like an economic downturn. This study also illustrated the challenge presented by a change in leadership change and its potential to disrupt a school’s trajectory of growth.