OBJECTIVES: To define racial similarities and differences in mobility among community-dwelling older adults and to identify predictors of mobility change. DESIGN: Prospective, observational, cohort study. PARTICIPANTS: Nine hundred and five community-dwelling older adults. MEASURES: Baseline in-home assessments were conducted to assess life-space mobility, sociodemographic variables, disease status, geriatric syndromes, neuropsychological factors, and health behaviors. Disease reports were verified by review of medications, physician questionnaires, or hospital discharge summaries. Telephone interviews defined follow-up life-space mobility at 18 months of follow-up. RESULTS: African Americans had lower baseline life-space (LS-C) than whites (mean 57.0 ± standard deviation [SD] 24.5 vs. 72.7 ± SD 22.6; P < .001). This disparity in mobility was accompanied by significant racial differences in socioeconomic and health status. After 18 months of follow-up, African Americans were less likely to show declines in LS-C than whites. Multivariate analyses showed racial differences in the relative importance and strength of the associations between predictors and LS-C change. Age and diabetes were significant predictors of LS-C decline for both African Americans and whites. Transportation difficulty, kidney disease, dementia, and Parkinson's disease were significant for African Americans, while low education, arthritis/gout, stroke, neuropathy, depression, and poor appetite were significant for whites. CONCLUSIONS: There are significant disparities in baseline mobility between older African Americans and whites, but declines were more likely in whites. Improving transportation access and diabetes care may be important targets for enhancing mobility and reducing racial disparities in mobility.