Central nervous system side effects associated with efavirenz are common, and for this reason it is recommended that the drug be taken at bedtime (Sustiva package insert). Neuropsychological performance and symptoms associated with efavirenz were carefully evaluated in AIDS Clinical Trials Group (ACTG) study 5097s (Clifford 2009). We plan to use similar assessments for the proposed study, to allow for comparison with historical controls. The assessments include questionnaires for assessment of sleep, depression, and anxiety. We will also administer a short battery of neuropsychological testing that has been shown to be sensitive to HIV-related neurocognitive impairment.