Priority Health is a non-profit health plan that serves more than 19,000 people with asthma in 43 Michigan counties. In the late 1990s, Priority Health recognized the need for home-based asthma care that includes environmental trigger management. To deliver effective home-based care, Priority Health formed a first-of-its-kind partnership with the Asthma Network of West Michigan (ANWM). Priority Health uses ANWM's case managers and social workers to increase its ability to effectively assess and educate its members. ANWM provides home-based education; home environmental assessments; and resources to reduce exposures to environmental asthma triggers. Today, all of the plan's members with moderate or high risk asthma within ANWM's service area receive intensive case management that integrates patient education, home-based environmental interventions, and evidence-based clinical care. Priority Health also reimburses ANWM for meeting with providers to develop individualized care plans. These plans are the cornerstone for determining appropriate interventions, monitoring, and follow-up. Priority Health provides incentives to their providers to ensure that members use asthma medications appropriately and to implement the Planned Care Model for asthma. The results of these programs include improved medication use and significant reduction in the number of emergency room visits and hospitalizations for asthma. Utilization data show that emergency room visits were reduced from 72 visits per thousand patients in 2002 to 40 in 2006 for commercial members, and from 250 to 189 for Medicaid members. Savings over time for members are estimated at $1.7 million, and the long-term return on investment (ROI) for Priority Health is 2.1:1.