The U.S. Food and Drug Administration (FDA) is considering approval of an over-the-counter, rapid HIV test for home use. To date, testimony presented before the FDA has been overwhelmingly supportive. Advocates have argued enthusiastically that there is value in empowering individuals to manage their HIV risks and have suggested that the availability of a rapid home HIV test will dramatically increase rates of disease detection in communities that have proven difficult to reach and to link to appropriate care. The authors offer a more cautious perspective. According to what is already known about the market demand for over-the-counter HIV testing kits, their costs, and the performance of rapid HIV tests in that market, the authors do not anticipate that the rapid home test will have a profound impact either on the HIV public health crisis or on the populations in greatest need. Home HIV testing will attract a predominantly affluent clientele, composed disproportionately of HIV-uninfected new couples and "worried well" persons, as well as very recently infected persons with undetectable disease. The authors illustrate how testing in these populations may have the perverse effect of increasing both false-positive and false-negative results. A poorly functioning home HIV test may thereby undermine confidence in the reliability of HIV testing more generally and weaken critical efforts to expand HIV detection and linkage to lifesaving care for the estimated 300,000 U.S. citizens with unidentified HIV infection.