The prevalence and impact of adult asthma are substantial, and poor self-management practices, especially failures to adhere to treatment regimens, appear to be a significant problem. Desirable characteristics of an intervention program to improve self-management were identified through needs assessment and review of existing patient education resources. A comprehensive program was developed that integrated a workbook with one-to-one counseling and adherence-enhancing strategies. A longitudinal 1-year study compared patients receiving this self-management program with "usual care" patients receiving standard asthma pamphlets. Patients were randomly assigned to conditions. Baseline score and asthma severity were statistically controlled. Self-management patients had substantially better adherence than usual care patients, as well as improved functional status, at follow-up. Hospital and emergency department visits decreased in both groups but did not differ between groups.