Through a series of summit meetings, the Adult Education Great Cities Summit Initiative explored the needs and concerns of adult education students, teachers, and local program administrators in five large, urban settings. Chicago, Los Angeles, New York, Miami, and Houston participated in a series of activities focused on improving learner outcomes, enhancing teacher capacity for providing evidence-based instruction, accessing evidence-based resources, and technical assistance in building capacity for coordination among key partners. As part of this activity, four policy briefs were developed based on key topics that emerged from the Great Cities Summit discussions. This policy brief, From Ghost Systems to Host Systems via Transformation Zones, focuses on the convergence of advances in implementation, organization change, and system reinvention science and practice towards effective and efficient changes in large education and human service systems. [This report was produced under contract with Barrera Associates, Inc.]