The effects of age-related sensorimotor and central processing deficits on postural control are reviewed, and the paucity of knowledge about proprioceptive changes with age is noted. A model of processing stages in the production of responses to postural instability is outlined. Even slight response slowing produces disproportionate increases in clinically slow responses. Many aspects of postural responses are "cognitively penetrable". Research on falls should examine learned as well as automated behaviors.