The spondyloarthritides are group of interrelated and overlapping arthritic conditions which primarily include ankylosing spondylitis, reactive arthritis/Reiter's disease and arthritis associated with psoriasis and inflammatory bowel disease. They are characterised by the absence of rheumatoid factor and by association with HLA-B27 antigen. The main clinical features are inflammatory back pain, spondylitis, sacroileitis, asymmetric arthritis of lower limbs, enthesitis, dactylitis, besides fatigue, uveitis, skin and mucous membrane lesions, cardiac and pulmonary involvement. Although there are similarities among the spondyloarthritides, each of them have specific characteristic that help us to distinguish them.