Adherence to prescribed antiretroviral therapy (ART) is one of the strongest predictors of progression to AIDS and death among people living with HIV/AIDS. Incorrect or inconsistent adherence to ART compromises the effectiveness of medications in achieving viral suppression. The objective of this review is to systematically and critically appraise existing evidence on the use of electronic reminder devices (ERDs) to improve adherence to ART among people living with HIV/AIDS. Twelve electronic databases not limited by language or nationality were systematically searched using a combination of relevant search criteria through early August 2007. Primary outcomes of interest were level of adherence and virologic or immunologic response. Ten intervention studies, 5 qualitative studies, and 6 unpublished studies presented in conference abstracts were included. Methodological limitations across the 15 published studies precluded meta-analysis. Evidence that patient adherence to ART was significantly improved with the use of an ERD was reported in 4 of the 8 included studies that examined ERD use as a stand-alone adherence strategy. Patient satisfaction with devices was noted across studies, and conflicting evidence of improved virological and immunological outcomes was reported in the two studies that included such measures. The authors conclude that there is a lack of definitive data resulting in insufficient evidence about the effectiveness of ERDs as strategies for improving patient adherence to antiretroviral medications. Further and more rigorous research is warranted.