The dissemination of complex innovative practices is one of the major challenges of mental health service organizations. Although substantial progress has been made in the development of evidence-based practices for people with severe mental illness, development of approaches for the large-scale dissemination of such practices has lagged. In 2004, the Veterans Health Administration began a national dissemination effort of supported employment (SE). Concomitant with the clinical initiative, a research project was funded to study the factors that promote successful program implementation through an evaluation of the effectiveness and cost-effectiveness of two levels of training in the evidence-based practice of SE. This article reviews the dissemination effort and associated research project. This initiative represents the largest dissemination effort of any psychosocial rehabilitation model to date in any single healthcare system in the United States. We review the dissemination plan, including development of a mentor-trainer system at two intensity levels, regular on-site and telephone training and supervision, ongoing fidelity evaluation, and national outcomes monitoring with a Web-based data collection system.