With the aging of the US population, the proportion of African-Americans will increase and older adults in rural areas will become more isolated. Gender differences in health and function can be expected to be worse in historically underserved populations. Maintenance or improvement of mobility is critical to maintaining not only quality of life, but also physical and mental health. The University of Albama at Birmingham Study of Aging was designed to understand racial differences in mobility among older adults, and the study cohort is balanced by race, gender and rural-urban residence. Thus, the study can provide insights into the impact of aging on the health and function of African-American and white men and women in both rural and urban areas. The study demonstrates that mobility is a complex functional domain impacted by sociodemographic, general-health and mental-status factors. As modifiable risk factors of life-space mobility decline are identified, this will lead to the development and testing of interventions designed to enhance mobility among diverse populations of older adults in both rural and urban settings. © 2006 Future Medicine Ltd.