Eligible adult patients (>= 13 years of age) will receive treatment with Viramune once daily for 2 weeks and then twice daily. Eligible pediatric patients (< 13 years of age) will receive a lower dose of Viramune once daily for 2 weeks and then twice daily. All patients will receive Viramune with or without concomitant antiretroviral therapy. Patients will be evaluated at weeks 2, 4, 8, 16, 24, 32 and every 8 weeks thereafter.