In this study, using a questionnaire, data were collected about the disease, the working conditions and problems, the working ability, the unemployment and the invalidity of 1134 patients suffering from ankylosing spondylitis (Bechterew's disease). In 739 cases (65.2%) a statistical evaluation could be made. 62.2% had pain when working; the reasons were most often the long working time, the position at work, and the climatic factors at the workplace. The solutions to working problems were often applied too late or they did not correspond to the needs of the patients with ankylosing spondylitis. Generally the working ability was with 97.3% high and the invalidity with 2.7% low.