Ankylosing spondylitis (AS) is a common (prevalence 0.2-0.9%) chronic inflammatory disease that mainly affects young males and is characterised by inflammatory back pain with sacroiliitis and often arthritis of the peripheral joints. The disease can lead to deformities of the vertebral column, joints and extra-spinal structures, e.g. the eye (uveitis). Non-steroidal anti-inflammatory drugs (NSAIDs) and physical therapy seem to improve the long-term outcome of AS. However, the effect of disease modifying antirheumatic drugs (DMARDs) is less impressive compared with other rheumatic diseases, such as rheumatoid arthritis (RA). In placebo controlled trials, sulfasalazine showed some improvement of disease activity, especially in spondyloarthropathy patients with peripheral arthritis. Altogether the number of therapeutic options for AS is limited and other drugs, such as leflunomide or thalidomide, should be explored further in placebo-controlled trials.