The effect of a triage and care system, which employs continued patient education, alternatives to emergency department (ED) care for nonemergent problems, and close cooperation between ED staff and the primary care physician on inappropriate ED use, was analyzed for three groups of patients: (a) Medicaid patients, all of whom had unrestricted access to the ED; (b) group A patients who required prior physician approval and copayments for all ED services; and (c) patients enrolled in group B who were responsible for copayments only and did not require prior physician approval for ED use. Two hundred ninety-nine (299) charts were prospectively reviewed for age, payer status, date, time of visit, diagnosis, outcome of visit, and severity of illness. Medicaid patients utilized the ED much more than expected, compared to either group A or B patients (P < 0.001). Expected rates of utilization were based upon that particular group's representation in a medical associate's patient panel, which was based upon patient billing data. Medicaid patients were significantly younger than group A or B patients (P < 0.001) and had lower severity scores (P = 0.04). Our triage and care system failed to alter patterns of ED utilization for Medicaid patients.