Automated DOT (a-DOT), a smartphone app that uses facial recognition software and advanced features to detect non-ingestion, combines the accuracy of in-person DOT with the convenience of real-time centralized data collection and monitoring. Adding a daily sexual diary will allow precise tracking of the timing of both tenofovir/emtricitabine (TDF/FTC) ingestion and sexual risk episodes for evaluation of intermittent regimens. So, the project team is building and evaluating a new adherence measurement technology, DOT Diary (D2) that integrates a-DOT and a daily sexual diary on a smartphone platform. This adherence tool meets all four criteria of an optimal adherence measure: (1) provides evidence of medication ingestion, (2) precisely tracks longitudinal patterns of adherence, (3) provides real-time adherence monitoring, and (4) allows for individual feedback on adherence performance and tailored adherence support interventions. This adherence measurement and potential adherence intervention tool is being tested in young men who have sex with men in Atlanta and San Francisco. RTI International has been involved with the formative research and qualitative data collection and analyses activities at the San Francisco site.