Patients receive treatment with ZDV, 3TC, ABC, and APV daily for 24 weeks. Clinic visits occur weekly until Week 4, then every 2 weeks until Week 12, then monthly. Blood and urine samples are collected and patients are monitored for clinical or laboratory abnormalities. Laboratory tests to assess side effects and virologic and immunologic parameters, including viral quantification of CSF on all chronically infected patients and selected consenting acutely infected patients, are determined. In a pharmacoeconomic component of this study, patients have interviews and complete questionnaires at 5 clinic visits.