2.a) Survey module. First, a survey questionnaire will be conducted with young adults ages 18 to 25 to learn about their survival expectations, perceptions of HIV risks and treatment, future-oriented behaviours such as smoking, alcohol use, HIV risk behaviors, savings, locus of control, mental health, time and risk preference, and life satisfaction. In addition, a subset of questions from the Ravens Standard Progressive Matrices (SPM) will be used to rapidly and robustly assess study participants' cognitive ability. The SPM is a non-verbal measure of general intelligence used widely in South Africa and previously validated for use in this community.