This investigation applied a diagnostic and treatment protocol to two groups of industrial workers: 5,300 employees at Potomac Electric Power Company ( PEPCO ) for two years and 14,000 United States Postal Service workers for one year. An "active" system in which patients were evaluated weekly was implemented at the power company, and a "passive" system in which patients were seen only once was instituted at the U.S. Postal Service. The physicians were unbiased , in that they could not take part in the patients' ongoing care. The results in both groups demonstrated significant and continuous reductions in number of incidents, in days lost from work, in low-back surgery, and in financial costs. The number of low-back pain patients at PEPCO decreased 29% the first year and 44% the second; days lost from work decreased 51% the first year and 89% the second; low-back surgery dropped 88% the first year and 76% the second year. Results for the U.S. Postal Service demonstrated a decrease in the number of low-back pain patients (41%), in days lost from work (60%), and in financial costs (55%). These results, along with our observations about the study, led us to the following conclusions: (1) Good medicine leads to cost savings in treating industrial low-back pain. (2) Use of a standardized medical approach and nomenclature is necessary and practical, for consistent care. (3) A good record keeping system is essential to perform useful medical analyses for identifying scientific problems. (4) Unbiased medical surveillance leads to changes in behavior of both treating physicians and patients. (5) The outcome for most low-back pain patients in industry is not as grim as previously perceived if their medical management is approached in an organized manner.