Background: Ankylosing spondylitis (AS) belongs to a group of related disorders called spondyloarthropathies. It is the most common and most typical form of spondyloarthropathy. Men are usually affected three times more than women. The disease is characterized with inflammatory back pain starting in adolescence and early adulthood. When patients are diagnosed after the age of 45 years, it is possibly because symptoms over the years have been minimal. Methods: This was a prospective study of patients that were seen in the rheumatology out-patients department of a specialist hospital over a period of one year. A detailed history of back pain, heel pain, enthesopathy and peripheral arthritis were obtained. Histories of conjunctivitis, urethritis, inflammatory bowel disease and family history of ankylosing spondylitis were obtained. Inclusion criteria were patients that were previously diagnosed as AS and those who met the modified New York criteria for classification of AS. A thorough examination of spinal and extra-spinal regions was carried out. Investigations carried out included rheumatoid factor, tissue typing, plain radiograph and magnetic resonance image of the sacroiliac joints. Results: There were 840 patients that presented in the rheumatology clinic over the study period. Thirty two patients presented with various spondyloarthropathies while 12 of them were diagnosed as ankylosing spondylitis. Male to female ratio was 11: 1. The age range of the patients was 18 - 54 years with a mean of 46 ± 4 years. The duration of symptoms varied between 9 months to 28 years. Frequencies of initial presentation were low back pain in five, peripheral arthritis in four, heel pain in two and uveitis in one patient. Extra–articular presentations included aortic incompetence, pulmonary fibrosis and non-specific abdominal pain. All the patients had sacroiliitis. Joint involvement was asymmetrical and joints of the lower limbs were majorly affected. Test for rheumatoid factor was