Â© 2007 by Taylor & Francis. Mobility is a functional ability that is important for maintaining quality of life and independence, particularly with advanced age. Continued mobility is crucial for maintaining social contacts, independent functioning, and a satisfying quality of life. An important index of mobility, particularly in the United States, is driving. Most older adults in the United States rely primarily on the personal automobile for maintaining mobility (Jette & Branch, 1992). Fifteen years ago almost 90% of older adults in the United States relied on the personal automobile for the majority of their transportation needs (Transportation Research Board, 1988), and dependence upon the personal automobile is only increasing (Mollenkopf et al., 2002). As the number of older drivers both in the United States and abroad and the amount they drive is increasing, dependence upon driving to sustain quality of life is mounting as well (Owsley, 2002).