Ankylosing spondylitis is more common in young men than in young women and is insidious in onset. Typically, patients complain of pain and stiffness around the sacroiliac region. At the disease progresses, pain is often felt in the mid-lumbar, thoracic and cervical regions resulting in a significant reduction in the range of motion of the entire spine. About one fourth of the patients display involvement of proximal synovial joints. Acute anterior uveitis may precede AS or can occur when the disease is otherwise in apparent remission. Each patient with established disease should be carefully evaluated for cardiovascular, pulmonary, and neurologic complications. Early detection of AS is important, since proper management may well prevent the severe fixed deformities of the spine and root joints that is liable to occur in these patients.