 Addiction treatment is often characterized by long delays between first contact and treatment as well as high no-show and drop out rates leading to unused capacity in apparently full agencies. Patients do not get needed care and agency financial stability is threatened. The Network for Improvement of Addiction Treatment NIATx began as a high-intensity improvement collaborative of 39 addiction treatment agencies distributed across 25 states. NIATx substantially improved time to treatment and continuation in treatment by making improvements to organizational processes such as first contact, intake and assessment, engagement, level of care transitions, paperwork, social support, outreach, and scheduling in preliminary studies. While the results are very encouraging, they have, by intent, been obtained from a select group of agencies using a high-cost combination of services. A more practical diffusion model is needed to spread process improvements across the spectrum of treatment agencies. This study is a cluster-randomized trial to test the effectiveness and cost of less expensive combinations of the services that make up the NIATx collaborative interest circles, coach calls, coach visits and learning sessions. 