This article compared a group of individuals with complaints of chronic ankle instability (CAI) to a control group performing a series of movements where the subjects stand on one leg and reach for a target with the other foot. A battery of these “reach tests” in the 8 “compass” directions has become known as the Star Excursion Balance Tests (SEBT). The SEBT has been proven in previous research to be reliable, and valid for documenting deficits in lower extremity function. The authors looked at the traditional reach distance and error at hitting the target. They also used motion capture and force plate analysis to gain a greater understanding of these deficits.