Studies have found that adults with possible mild cognitive impairment (MCI) exhibit decrements in everyday functioning (e.g., Wadley, V. G., Crowe, M., Marsiske, M., Cook, S. E., Unverzagt, F. W., Rosenberg, A. L., et al. (2007). Changes in everyday function among individuals with psychometrically defined mild cognitive impairment. Journal of the American Geriatrics Society, 55, 1192-1198). However, it is not known whether driving mobility and life space mobility are reduced in such individuals. The current study examined 5-year trajectories of mobility change in older adults (N = 2,355) with psychometrically defined MCI from the Advanced Cognitive Training for Independent and Vital Elderly trial. Mixed effect models evaluated group differences for the following mobility outcomes: driving space, life space, driving frequency, and driving difficulty. Relative to cognitively normal participants, participants with possible MCI showed reduced baseline mobility for all outcomes as well as faster rates of decline for driving frequency and difficulty. These results suggest that mobility declines could be features of MCI, and changes in mobility may be particularly important for researchers and clinicians to monitor in this population. © The Author 2010. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved.