Adherence to ART is critical for treatment success at the individual level and to avoid the onset of resistant strains of HIV. In Peru, where ART has recently been introduced, adherence to HIV treatment has not yet been addressed properly. Innovative approaches using information technologies such as cell phones are needed to increase adherence to ART for people with HIV/AIDS. The specific aims of the study are to: 1) Conduct formative research to assess culturally-specific behavioral messages to be included in the computer-based system; 2) Develop and test an interactive computer-based system using cell phones to enhance adherence to ART and to deliver HIV transmission risk reduction messages; 3) Evaluate the impact of the system on antiretroviral adherence and sexual risk behaviors.