We compared the relative effectiveness of 2 arthritis patient education interventions. One intervention was modeled after that developed by Lorig, whereas the other had similar content but used health professionals rather than laypersons as instructors. Both interventions resulted in an increase in patients' knowledge of arthritis and in their use of exercise compared with a control group that received no intervention. However, neither intervention was any more effective than nonintervention in lessening patients' pain, improving their functioning, enhancing social support systems, lessening their depression, or improving their health behaviors beyond that of exercise. No differences in outcome measures were found between groups led by professional instructors and those led by lay instructors.