As HIV infection rates continue to rise, more and more people are faced with a complex, life-altering highly active antiretroviral therapy (HAART) regimen. With some researchers reporting as few as 50-70% of patients achieving adherence in the first six months of a HAART regimen, many behavioral interventions to increase HAART adherence have been examined. One such intervention, motivational interviewing (MI), has shown promise in previous studies and reviews as a possible successful intervention. Researchers conducted a review of the literature to identify studies analyzing the effect of a MI intervention on HAART adherence, with the objectives of examining this relationship and identifying gaps in the literature. To draw definitive conclusions about these questions and to maintain high methodological quality in the search, researchers used the Cochrane method for systematic reviews while conducting this review. Five studies were retained for review from the search and all were RCTs. Sample sizes ranged from 141 to 326 patients. Three of the five studies showed a significant increase in adherence rates, two studies reported a significant decrease in viral load, and one study showed an increase in CD4 cell count as a result of the intervention. A lack of a universally accepted definition of adherence and large gaps in the areas of humanistic and economic outcomes in the literature creates challenges in comparing improvements in HAART adherence across studies. Despite these challenges in comparison, MI appears to be a promising intervention to improve HAART adherence in HIV-positive individuals, but further studies of rigorous methodological quality are needed to fully understand the effect of this intervention.