Assessment of the status and prognosis of an HIV-infected individual traditionally has been difficult for the clinician. The use of markers of disease progression such as CD4+ has been found to not be a complete indicator of the status of an HIV-infected individual. As a result, determining appropriate therapy for the treatment of this viral infection has been both unpredictable and challenging. Recent development of a laboratory assay has brought a new tool in the management of HIV. The assay is a quantitation of the amount of detectable HIV RNA and estimates the amount of HIV viral load or HIV viral burden present in the blood. Since the development of this assay, HIV RNA quantitation has rapidly become an important surrogate marker of HIV infection. In addition, this quantitation is used to determine the effectiveness of anti-HIV therapies. Understanding the differences and results of quantitative assays is imperative in the management of HIV-infected patients. This article summarizes the events leading to the creation of quantitative assays, explanations and comparisons of the current quantitative assays, and nursing considerations for the implications and uses of viral load markers.