This article describes a 20+-year learning collaboration between a clinical psychology program and a state mental health department focused in part on the joint mission of educating and training doctoral students in the development and implementation of data-based decision making in public mental health systems of care. Funded by the state government, the collaboration was designed to assure meaningful contributions to service improvement and to prepare doctoral psychology students for leadership roles in public service. This partnership provided paid graduate assistantships and opportunities for students and others to contribute to accumulated clinical science via practice-based research. We provide a brief contextual overview of events that set the stage for the university/state department team-up; the vision, goals, and structural processes of the collaborative training opportunity; and students’ roles and educational objectives. We then describe outcomes to date including contributions to the system of care and clinical science, placement of students and early-career staff in public service leadership positions, and students’ retrospective perceptions of their learning and development affected by their training experiences in the collaboration. Finally, the authors discuss implications and recommendations for universities that might consider implementing such a partnership.