Premature morbidity and mortality from chronic diseases account for a major proportion of expenditures for health care cost in the United States. The purpose of this study was to measure the effects of a disease management program on physiological and behavioral health indicators for Medicaid patients in Florida. A two-year prospective study of 15,275 patients with one or more chronic illnesses (congestive heart failure, hypertension, diabetes, or asthma) was undertaken. Control of hypertension improved from baseline to Year 1 (adjusted odds ratio = 1.60, p < .05), with maintenance at Year 2. Adjusted cholesterol declined by 6.41 mg/dl from baseline to Year 1 and by 12.41 mg/dl (p < .01) from baseline to Year 2. Adjusted average medication compliance increased by 0.19 points (p < .01) in Year 1 and 0.29 points (p < .01) in Year 2. Patients in the disease management program benefited in terms of controlling hypertension, asthma symptoms, and cholesterol and blood glucose levels.