This is a proposal to develop a Balanced Reach Training Protocol (BRTP) to evaluate and train dynamic standing balance. The BRTP is based upon the Balanced Reach Test (BRT) that the investigators previously developed and validated. In the BRT subjects stand and point to a target disk moving unpredictably across a large projection screen in front of them without stepping. Body movements undertaken to track the disk are integral to many daily activities and represent an important class of expected balance disturbances that can precipitate falls. The BRTP employs engineering and psychophysical methods, and exploits advances in real time computing in a novel and innovative way to more effectively evaluate and train balance function. The BRTP presents a challenging reaching/tracking task that subjects perform at their limit of balance. The BRTP is an objective, quantitative test that can evaluate balance function without floor or ceiling effects, and train balance across the spectrum of aging, disease, and injury.