The present study (Back to Health) is a 52 week comparative effectiveness randomized controlled trial of once per week yoga classes, individually delivered physical therapy (PT), and education for chronic low back pain (CLBP) in 320 individuals from predominantly minority backgrounds recruited from Boston Medical Center and affiliated community health centers. The 52 week trial starts with an initial 12 week Treatment Phase followed by a 40 week Maintenance Phase. Back to Health has the following three specific aims: