Operative treatment of Ankylosing spondilitis is usually performed in treatment of extraspinal pathology, i.e. in treatment of hip contractures. Operative treatment of fixed spinal kyphosis in AS is rarely indicated, and patients make their decision for the operation when deformation becomes extreme. Instead of several hundred of operated patients in foreign literature, authors describe only 5 operations from 1989 to 2000. Results suggest that multiple spinal osteotomy in AS is a time consuming operation with a significant intraoperative and postoperative blood loss. Mild, transient radicular irritations are noticed. However, reconstruction of lumbar lordosis significantly improve quality of life in operated patients. It is concluded that indication for the operation in AS should be indicated earlier. Better results with less risk would be achieved.