This research examined whether cognitive behavioral therapy and mindfulness interventions that target responses to chronic stress, pain, and depression reduce pain and improve the quality of everyday life for adults with rheumatoid arthritis (RA). The 144 RA participants were clustered into groups of 6-10 participants and randomly assigned to 1 of 3 treatments: cognitive behavioral therapy for pain (P); mindfulness meditation and emotion regulation therapy (M); or education-only group (E), which served as an attention placebo control. The authors took a multimethod approach, employing daily diaries and laboratory assessment of pain and mitogen-stimulated levels of interleukin-6 (IL-6), a proinflammatory cytokine. Participants receiving P showed the greatest Pre to Post improvement in self-reported pain control and reductions in the IL-6; both P and M groups showed more improvement in coping efficacy than did the E group. The relative value of the treatments varied as a function of depression history. RA patients with recurrent depression benefited most from M across several measures, including negative and positive affect and physicians' ratings of joint tenderness, indicating that the emotion regulation aspects of that treatment were most beneficial to those with chronic depressive features.