Subtalar instability is a common clinical entity. Clinicians should have a high index of suspicion of this diagnosis in patients who have been diagnosed with chronic lateral ankle instability but have failed standard management and have continued pain in the sinus tarsi. As with ankle instability, nonoperative management is the initial mainstay of treatment. Operative management includes ligamentous reconstruction of key lateral stabilizers of the subtalar joint. Future research on this subject should be focused at improving diagnosis and recognition of this entity.