Context: Agility training has been proposed as an important tool in rehabilitation. However, it is unclear which types of agility training are most useful. Objective: To assess the effects of agility training on balance in individuals with functionally unstable ankles. Design: A 2-group experimental design with repeated measures. Setting: Laboratory. Patients: Twenty college-aged volunteers, each with 1 functionally unstable ankle, were randomly assigned to 1 of 2 groups. Interventions: Subjects in the experimental group performed agility training 3 times per week for 4 weeks. Main Outcome Measures: Subjects were tested for static single-leg balance before and after the training period. Anterior/posterior sway amplitude, medial/lateral sway amplitude, and sway index were assessed using the Chattex Balance System. Results: No significant differences in balance were found after the agility training. Conclusions: Agility training did not improve static single-leg balance in subjects with functionally unstable ankles.