Recent findings have led to important changes in the understanding of HIV kinetics that allowed a novel therapeutic approach. This article reviews the most common methods used to gauge viral load and their use in medical decision making, the characteristics of the protease inhibitors just released in Argentina, and preliminary reports from several trials of combined treatment that have changed the standard of care. The viral load is a surrogate marker with predictive value independent of the CD4 cell count. Combined treatment is the election in case it is decided to initiate treatment.