Geographically diverse POCs will be selected in the USA. Approximately 15-20 POCs are planned. Approximately 2,500 subjects will participate in the study including 1,500 subjects with unknown HIV status and 1,000 seropositive subjects. Across these POC sites, voluntary testing of 1500 subjects with unknown HIV status is planned with at least 500 of these subjects being high risk. Samples will be obtained from consenting subjects in the voluntary testing population including high-risk and known HIV 1 seropositive individuals.