The baseline HANDLS sample will consist of approximately 4,000 community-dwelling African American and White adults aged 30-64.  Participants will be drawn from 12 pre-determined census tracts in Baltimore City so as to sample representatively across a wide range of socioeconomic and income circumstances.  The heuristic study design is a factorial cross of 4 factors: age, sex, race, and socioeconomic status.  HANDLS is planned as a 20-year longitudinal study.  Using our mobile research vehicles, we will visit each census tract for three months and we will re-visit every census tract in a three-year cycle.