The effects of outpatient group cognitive therapy, relaxation training, and cognitive therapy in combination with relaxation training on chronic low back pain and associated physical and psychosocial disability were evaluated and compared. One-hundred and two mildly disabled chronic low back pain patients were assigned randomly to a waiting-list (WL) control condition and the 3 treatments. Patient self-report and observational measures were obtained pretreatment and post-treatment for all conditions, and at 6- and 12-month follow-ups for the treatment conditions. Pain intensity decreased significantly pre- to post-treatment for patients in all 3 treatment conditions, but not the WL condition. Depressive symptoms and disability improved significantly in all conditions (including the waiting list) from pretreatment to post-treatment, with no statistically significant differences among treatments. At both follow-ups, all 3 treatment groups remained significantly improved from pretreatment, with no statistically significant differences between treatments.