BACKGROUND Ball and socket ankle (BASA) deformity is a rare condition. Little is known about outcomes and treatments in the adult population. METHODS Retrospective comparative review was performed of 13 patients treated for BASA with a minimum follow-up of 2.5 years. Evaluation included clinical and radiographic review, outcome scores, a questionnaire, and a subjective satisfaction survey. RESULTS Nine patients with correctable valgus deformity not associated with arthritis of the ankle joint underwent a supramalleolar osteotomy (SMO). Four patients underwent arthrodesis-2 a tibiotalocalcaneal (TTC) arthrodesis and 2 a pantalar arthrodesis. AOFAS scores improved from 30.1 to 77.6 (range, 16-82) (P < .05) in the SMO group. AOFAS scores improved from 24 to 60.5 (range, 16-66) (P < .05) in the arthrodesis group. Arthritis grade in the SMO patients was unchanged in 4 patients at final follow-up and worsened in 5 patients by only 1 grade. Nine patients reported good results (all 4 arthrodesis patients, 5 SMO patients) and 4 reported fair results (all SMO patients). CONCLUSIONS BASA deformity and dysfunction can be improved with corrective surgery. METHODS Level III, prospective comparative study.