PURPOSE: This single-assessor-blinded randomized controlled trial aimed to compare the efficacy of physiotherapy-delivered clinical Pilates and general exercise for chronic low back pain. METHODS: Eighty-seven community volunteers with low back pain for ≥3 months and age 18-70 were randomized to either the Pilates (n = 44) or general exercise (n = 43) group. The primary outcome was pain/disability measured with the Quebec scale. Secondary outcomes included pain on a numeric rating scale, Patient-Specific Functional Scale, Pain Self-efficacy Questionnaire, quality of life, and global perceived effect of treatment. All participants attended 60-min exercise sessions twice weekly for 6 wk supervised by a physiotherapist and performed daily home exercises that were continued during the follow-up. Participants from the clinical Pilates group received an individualized direction-specific exercise program prescribed by the physiotherapist after a clinical examination. The general exercise group received a generic set of exercises that were multidirectional and nonspecific. Outcomes were assessed after 6 wk (primary time point) and at 12 and 24 wk. Differences in mean change were compared between groups using ANCOVA adjusted for baseline values of the outcome. RESULTS: Eighty-three participants (96%) completed the 6-wk intervention and 60 (69%) completed the 24-wk follow-up. At 6 wk, no difference was found between groups for change in the Quebec scale (3.5, 95% confidence interval = -7.3 to 0.3, P = 0.07); both groups showed significant improvements. Similar results were found at the 12- and 24-wk follow-up and for the secondary outcome measures. CONCLUSIONS: An individualized clinical Pilates program produced similar beneficial effects on self-reported disability, pain, function and health-related quality of life as a general exercise program in community volunteers with chronic low back pain.