The Agility total ankle replacement system was the most commonly performed implant in the United States for more than 20 years and has undergone four generations and seven phases of improvement. Much attention has been placed on intraoperative complications, such as malleolar fracture; nerve or tendon injury; and incision healing–related problems, such as wound coverage and infection. However, it is the intermediate- and long-term complications (ie, aseptic osteolysis, subsidence, component loosening, and progressive malalignment) that require careful consideration, because the revision options remain limited. This article reviews the history of the Agility total ankle replacement system in detail, to understand the revision possibilities available.