Spiegel, et al proposed for the first time in 1986 the inclusion of the Joint Alignment and Motion (JAM) Scale in the evaluation of patients with rheumatoid arthritis. Our 2-part study attempted to (1) measure the interobserver reliability of the instrument (therapist, occupational and physical vs physician) and (2) determine the relationship between it and disease severity as determined radiographically by means of the modified anatomical grading criteria, and functionally by the ARA functional class. Thirty patients were included in each part of the study. Our data indicate that the quick, inexpensive JAM Scale of Spiegel, et al is a reliable method of estimating joint motion and alignment and correlates with both functional class and disease severity.