Twenty-five adult patients with 32 fused hind-feet were evaluated at an average of 4.3 years after triple arthrodesis. All patients had Stage 3 or 4 deformity secondary to adult acquired flatfoot. All operations were performed using a standardized technique using rigid internal fixation. Postoperative American Orthopaedic Foot and Ankle Society hindfoot scores improved an average of 36 points. There was one nonunion and two residual varus malunions in patients who underwent additional procedures to obtain satisfactory position and fusion. All but one patient were satisfied with the result of their procedures and would have surgery again. With careful attention given to positioning, a triple arthrodesis is an acceptable treatment for late stage deformities in patients with adult acquired flatfoot.