The relationship between particular disabilities and specific impairments of which these disabilities could be the consequence has been explored. Assessments of performance of activities of daily living (ADL) have been simplified by factor analysis, and the resultant factors have been related to the sites of joint involvement in patients with rheumatoid arthritis. Our preliminary findings on the grouping together of various ADL activities are meaningful in terms of underlying impairments, and at the same time indicate an approach for simplification of ADL assessments so as to enhance their value for research and the evaluation of outcome. The results are entirely consistent with a comprehensive model of disablement.