Patients are screened for the presence of MDR virus and a plasma HIV RNA level greater than 10,000 [AS PER AMENDMENT 07/03/01: greater than 5,000] copies/ml. Eligible patients attend a baseline visit [AS PER AMENDMENT 07/03/01: and a subsequent randomization visit] where the qualifying GART results are provided. Patients who consent to participate have phenotypic antiretroviral resistance testing (PART) done on a specimen from the same blood draw that was used for the GART evaluation. After PART results are available, patients are randomized [AS PER AMENDMENT 07/03/01: If the predicted sensitivities are not available for some or all drugs included in the PART, the patient may still be randomized.] to either a 4-month STI followed by a new antiretroviral regimen or an immediate new antiretroviral regimen. The antiretroviral regimens chosen are based on the patients' history and both GART and PART results. [AS PER AMENDMENT 07/03/01: Additional GART and PART may be requested after at least 4 months of antiretroviral treatment.] Patients have the follow-up data collection done at Months 1-8 and every 4 months thereafter. Changes in antiretroviral therapy, Grade 4 adverse experiences, progression of disease, and deaths are reported as they occur. Patients are seen for clinical management as often as deemed necessary. All patients are followed to a common closing date estimated to be 24 months after the last patient is randomized. Some patients may participate in a Point Mutation Substudy [AS PER AMENDMENT 07/03/01: Plasma Point Mutation Substudy and PBMC Point Mutation Substudy].