In this study, scores on the sexual motivation scale (which measures the tendency to engage in sexual interaction versus the tendency to be averse to sexual interaction) were determined, by interview, in ankylosing spondylitis (AS) and rheumatoid arthritis (RA) patients and compared with the scores of healthy matched controls. AS patients did not score differently from the healthy population, but scores of men and women with RA were more in the direction of sexual aversion than those of healthy men and women. In female RA patients, some relationship was found between disease variables such as joint index and erythrocyte sedimentation rate and the score on the sexual motivation scale. In the second part of the interview, preference for certain coital positions was investigated, and the demand for help with sexual problems was explored. The percentage of RA patients expressing a need for advice was considerably greater than the percentage of AS patients.