Aspen and the Community College Research Center studied nine dual enrollment programs across three states--Florida, Ohio, and Washington--that have narrowed or closed equity gaps in dual enrollment for Black, Latinx, Indigenous, and Pacific Islander students. Based on this research, "The Dual Enrollment Playbook" describes the five principles that college and K-12 leaders can follow to design equitable dual enrollment programs. These five principles reflect the lessons that will make the most difference for historically underrepresented students of color, but these strategies may benefit students from low-income and other backgrounds as well. For each principle, the authors name several strategies, with examples, that the colleges and high schools they studied use to advance equitable access to and success in high-quality dual enrollment courses. When leaders apply these principles and champion practices and policies that prioritize equity as the ultimate goal, dual enrollment can truly accelerate the path to college and meaningful careers for all students. [For "Highlights from the Dual Enrollment Playbook: A Guide to Equitable Acceleration for Students," see ED608547.]