186 patients from Kristiansand who had been certified as sick for more than eight weeks because of low back pain were recruited consecutively and studied over a period of one year. 91 of these patients participated for three weeks in an out-patient programme involving physical activity and theoretical education. The control group (95 patients) consisted of 65 patients recruited before the treatment group and 30 recruited after the treatment group. The duration of certified sick leave was reported by the national Insurance Office of Kristiansand. The subjective ratings of low back pain, function and quality of life were stated by all subjects at the time of inclusion in the study and again after six and 12 months. The treatment group also stated their subjective assessment after the three weeks of intervention. The results show a significant improvement of low back pain, function and quality of life in the treatment group only, both following the intervention and after one year. 15% of the treatment group were still certified as unfit for work after one year, as against 23% of the one and 26% of the other control group. These differences were not, however, statistically significant.