College and career readiness has become a unifying principle for education reform leaders across the country. A majority of states have made it a top policy priority, with an increasing number of national foundations and education reform advocates supporting this work. To help state leaders build strategies for sustaining their education agendas over the long run, Achieve launched "Taking Root: Strategies for Sustaining the College- and Career-Ready Agenda." Through this project, Achieve conducted research on state education policies that have been sustained successfully to better understand the factors that had the most significant impact. Achieve focused on reforms in Indiana, Massachusetts, South Carolina and Texas because these states were able to sustain significant education reforms over at least a decade. This paper summarizes the lessons learned from Achieve's research in the four states and highlights examples and promising strategies from those states and others. Achieve also published separate case studies for each of the four states that go into greater detail on how their reforms were enacted and sustained. [For the state reports: "Taking Root: Indiana's Lessons for Sustaining the College- and Career-Ready Agenda," see ED512098; "Taking Root: South Carolina's Lessons for Sustaining the College- and Career-Ready Agenda," see ED512095; "Taking Root: Texas' Lessons for Sustaining the College- and Career-Ready Agenda," see ED512097; and "Taking Root: Massachusetts' Lessons for Sustaining the College- and Career-Ready Agenda," see ED512096.]