Investigators from the University of Michigan and the Institute for Social and Environmental Research in Nepal will collaborate in all proposed research capacity building and research activities. The study aims to enroll a cohort of 4,000 adults aged 50 and older, and conduct a baseline and one follow-up interview. The interview will include standardized assessment of cognitive and physical function, as well as a broad spectrum of other social, socio-economic and psychological instruments. The study will also collect blood samples of all participants as part of the baseline assessment. Data from this study will be analyzed by investigators from both participating institutions, and findings will be shared with relevant stakeholders in Nepal, and disseminated to the international literature on aging and dementia.