The recent decline in the cost of HIV antiretroviral therapy (ART) in India and the ongoing competition among generic manufacturers, combined with recent announcements by WHO and the Global Fund to Fight AIDS, TB and Malaria make it very likely that ART will soon be a viable option for a larger proportion of its HIV infected individuals. Unfortunately, treatment effectiveness requires high levels of adherence and the adherence literature on other chronic, infectious diseases in India, such as TB and leprosy, indicate that serious adherence barriers may exist. To date, there have been no published studies on ART adherence issues in India. Thus, there is an urgent need for research to better understand the forces that influence HIV treatment adherence in this culture. This essential research needs to include formative work to establish valid and culturally appropriate adherence measures and strategies, explore culturally specific interpersonal, interpersonal, and contextual adherence barriers and facilitators, and assess current rates and correlates of ART adherence. We also need a better understanding of provider behaviors, including the guidelines physicians follow when deciding to prescribe antiretroviral medication, how their decisions are influenced by patient characteristics, how adherence is monitored, and the extent to which these drugs are available to the population of HIV infected individuals in India. The proposed study has been designed to meet these needs. Its overall goal is to examine patient and provider ART adherence issues in the HIV clinic at St John's hospital in Bangalore, India. Culturally appropriate adherence measures will be identified and barriers that interfere with adherence to HIV treatment as well as potential avenues to enhance adherence will be examined using both qualitative and quantitative methods. These data will subsequently be used to inform the development of an adherence intervention that can be evaluated in a future clinical trial. The study includes two phases in which we propose to: 1. Conduct qualitative interviews with 40 patients and 20 physicians at St John's hospital in Bangalore, India to: a) Assess prescription patterns and clinical monitoring of toxicity and medication efficacy as well as perceptions of patient adherence; b) Explore individual, interpersonal and environmental factors that may facilitate or hinder adherence to HIV treatment regimens among HIV infected clinic patients; c) Examine the feasibility and acceptability of US developed adherence measures and strategies in this setting and determine ways in which these measures and strategies may need to be modified. 2. Recruit and follow a longitudinal cohort of 180 HIV infected clinic patients for one year using a computer-assisted structured interview to: a) Evaluate ART adherence patterns as well as adherence barriers and facilitators; b) Compare the concordance between the subjective and objective measures and HIV plasma viral load. [unreadable] [unreadable]