STUDY DESIGN: Prospective cohort study. OBJECTIVE: To assess the effect of 6 weeks of balance training on sensorimotor measures previously found to be deficient in participants with chronic ankle instability (CAI). BACKGROUND: CAI is the tendency toward repeated ankle sprains and recurring symptoms, occurring in 40% to 70% of individuals who have previously sustained a lateral ankle sprain. Recent studies have found deficits in sensorimotor measures in individuals with CAI. As balance training is a common component of ankle rehabilitation, understanding its effect on the sensorimotor system in individuals with CAI may enable us to optimize protocols to better utilize this rehabilitation method. METHODS: Twelve participants with CAI and 9 healthy volunteers participated. Independent variables were group (CAI, control) and time (pretraining, posttraining). Participants with CAI who completed a 6-week balance training program and healthy controls who did not get any training were pretested and posttested at the beginning and at the end of 6 weeks. RESULTS: The individuals in the CAI group who performed balance training demonstrated better performance than control participants on baseline-adjusted posttraining measures of dynamic balance in the anterior medial (P = .021), medial (P = .048), and posterior medial directions (P = .030); motoneuron pool excitability Hmax/Mmax ratio (P = .044) and single-limb presynaptic inhibition (P = .012); and joint position sense inversion variable error (P = .017). It may be of note that no systematic differences were detected for static balance or plantar flexion joint position sense tasks. CONCLUSIONS: After 6 weeks of balance training, individuals with CAI demonstrated enhanced dynamic balance, inversion joint position sense, and changes in motoneuron pool excitability compared to healthy controls who did not train.