Low-back pain is a major health and socio economic problem. Functional restoration programs (FRP) have been developed to promote the socio-professional reintegration of patients with important work absenteeism. The aim of this study was to determine the long-term effectiveness of FRP in a group of 105 chronic low-back pain patients and to determine the predictive factors of return to work. One hundred-and-five chronic LBP patients with over 1 month of work absenteeism were included in a FRP. Pain, professional status, quality of life, functional disability, psychological impact, and fear and avoidance beliefs were evaluated at baseline, after 1 year and at the end of follow-up. Main effectiveness criterion was return to work. Fifty-five percent of the patients returned to work after mean follow-up time of 3.5 years, compared with 9% of the patients at work at baseline. Quality of life, functional disability, psychological factors, and fear and avoidance beliefs were all significantly improved. Three predictive factors were found: younger age at the onset of low-back pain, practice of sports, and shorter duration of sick leave at baseline. FRP show positive results in terms of return to work for chronic LBP patients with prolonged work absenteeism. Efforts should be made to propose such programs at an earlier stage of the disease.